EP0460392A1 - Process for making foamed metal bodies - Google Patents

Process for making foamed metal bodies Download PDF

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Publication number
EP0460392A1
EP0460392A1 EP91106755A EP91106755A EP0460392A1 EP 0460392 A1 EP0460392 A1 EP 0460392A1 EP 91106755 A EP91106755 A EP 91106755A EP 91106755 A EP91106755 A EP 91106755A EP 0460392 A1 EP0460392 A1 EP 0460392A1
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EP
European Patent Office
Prior art keywords
metal
blowing agent
temperature
powder
particles
Prior art date
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Granted
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EP91106755A
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German (de)
French (fr)
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EP0460392B1 (en
Inventor
Hartmut Dr.-Ing. Schrader
Joachim Dipl.-Phys. Baumeister
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Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
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Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
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Priority claimed from DE19904018360 external-priority patent/DE4018360C1/en
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Publication of EP0460392A1 publication Critical patent/EP0460392A1/en
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F13/00—Arrangements for modifying heat-transfer, e.g. increasing, decreasing
    • F28F13/003—Arrangements for modifying heat-transfer, e.g. increasing, decreasing by using permeable mass, perforated or porous materials
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/10—Sintering only
    • B22F3/11—Making porous workpieces or articles
    • B22F3/1121—Making porous workpieces or articles by using decomposable, meltable or sublimatable fillers
    • B22F3/1125—Making porous workpieces or articles by using decomposable, meltable or sublimatable fillers involving a foaming process
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F7/00—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression
    • B22F7/002—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of porous nature
    • B22F7/004—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of porous nature comprising at least one non-porous part
    • B22F7/006—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of porous nature comprising at least one non-porous part the porous part being obtained by foaming
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
    • B22F2998/10—Processes characterised by the sequence of their steps
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12479—Porous [e.g., foamed, spongy, cracked, etc.]

Definitions

  • the invention relates to methods for producing foamable metal bodies and their use.
  • porous metal materials can be produced.
  • a simple method for producing these materials is the mixing of gas-releasing substances in molten metals.
  • the blowing agent decomposes with the release of gas due to the effect of temperature. This process leads to the foaming of the molten metal.
  • After completion of the process there is a foamed metal material which has an irregular, random shape.
  • This material can be further processed into bodies of the desired shape by appropriate processes.
  • only separation processes are suitable as processes for further processing, and consequently not every metal body can be formed from such a metal material.
  • Other processes for the production of porous metal materials also have similar disadvantages, such as, for. B. impregnation of an existing plastic foam with a slurry of metal powder and a carrier medium and a subsequent burning out or evaporation of the plastic foam after drying.
  • this method is very complex.
  • the object of the present invention is to provide a process for the production of foamable metal bodies which is inexpensive, simple to use, can be carried out without high forming outlay and at the same time can be used for blowing agents with a low decomposition temperature.
  • Another object of the invention is to propose a use of the foamable bodies produced in this way.
  • metal hydrides such as titanium hydride, carbonates, e.g. calcium carbonate, potassium carbonate, sodium carbonate, sodium bicarbonate, hydrates, e.g. B. aluminum sulfate hydrate, alum, aluminum hydroxide or easily evaporating substances, such as mercury compounds or powdered organic substances.
  • This intensely mixed powder mixture is compressed by hot pressing or hot isostatic pressing into a compact, gas-tight body. In the compacting process, it is of crucial importance according to the invention that the temperature is selected so high that the connection between the individual metal powder particles is predominantly made by diffusion.
  • the pressure is chosen so high that the decomposition of the propellant is prevented and a compact body is formed in which the metal particles are in a fixed connection with one another and form a gas-tight seal for the gas particles of the propellant.
  • the blowing agent particles are thus "trapped" between the interconnected metal particles, so that they only release gas in a later step of foaming. So can also be used with blowing agents whose decomposition temperature is below the compacting temperature. By applying the high pressure, these blowing agents do not decompose.
  • This measure according to the invention allows the use of blowing agents, the selection of which can only be chosen on the basis of compatibility with the selected metal powder or on the basis of the efficiency of the method.
  • the suitable choice of the process parameters temperature and pressure ensures that a body is produced which has a gas-tight structure. Furthermore, the fact that the propellant gas remains “trapped” between the metal particles prevents it from escaping prematurely from the compacted body. Accordingly, the amounts of blowing agent required are small. Blowing agent proportions of the order of a few tenths of a percent by weight are sufficient because the compacted body is completely compressed and the propellant gas cannot escape. Amounts of blowing agent from 0.2 to 1% have proven to be particularly favorable. Only the amount of blowing agent that is necessary to produce a foam structure has to be added. This leads to cost savings. Furthermore, it is advantageous that, due to the selected high temperature and the application of the high pressure, the compacting process takes place in a short time
  • An advantageous feature of the method according to the invention is that after the hot compaction process has ended, both the heat and the pressure are released simultaneously.
  • the still hot metal body keeps its shape even though there is no longer any pressure. This means that the metal particles form such a tight seal for the blowing agent powder particles that there is no expansion of the blowing agent, even at elevated temperature.
  • the metal body produced in this way is dimensionally stable and retains its shape even under elevated temperature and without the action of pressure.
  • the invention provides the addition of reinforcing components in the form of fibers or particles made of suitable materials, such as Ceramics before. These are advantageously added to the starting powders.
  • the starting materials and the foaming parameters in particular should be selected so that a good wetting of the reinforcement components by the metal matrix is guaranteed. It is advantageous if the fibers or particles are coated (e.g. with nickel). This ensures that the forces from the metal matrix are introduced into the particle / fiber.
  • Another method for producing foamable metal bodies is rolling at an elevated temperature of a powder mixture consisting of at least one metal powder and at least one blowing agent powder. This creates a connection between the metal and blowing agent powder particles in the roll gap.
  • the peculiarity of the person skilled in the art applies here that the diffusion between the particles occurs to a sufficient extent even at lower temperatures, in the temperature range around 400 ° C. for aluminum. These processes occur particularly in the surface layers.
  • the temperature range between 350 ° C and 400 ° C has proven to be particularly advantageous with aluminum rollers.
  • the measure of intermediate heating of the pre-rolled material after the individual roll passes is important, since this largely prevents the occurrence of edge cracks.
  • the method according to the invention provides that if the reinforcement is to be aligned along a preferred direction, this can be brought about by reshaping the foamable body. This transformation can e.g. by extrusion or rolling.
  • the invention provides that two or more blowing agents with different decomposition temperatures are mixed into the metal powder. If a foamable body produced from this powder mixture is heated, the blowing agent with the lower temperature first decomposes and causes foaming. If the temperature is increased further, the blowing agent decomposes at the next higher decomposition temperature and causes further foaming. The foaming takes place in two or more stages. Such gradually expanding foamable metal bodies have a particular application, e.g. in fire protection.
  • a particular advantage of the method according to the invention is that it is now possible to produce bodies which have a continuously or discontinuously changing density over their cross section, so-called graded materials.
  • An increase in density toward the edge of the foamable body is preferred since this is where the primary stress occurs.
  • a foamable body with a solid cover layer or a cover layer with a higher density offers advantages in terms of joining and joining with materials of the same or a different type. If the process of hot compacting is carried out in a mold, the powder mixture being wholly or partly surrounded by a metal or metal powder free of blowing agent, the blowing agent-free metal layers form fen.
  • the blowing agent-free metal layers each form a solid, less porous outer layer or bottom layer or cover layer, between which there is a layer which, after a foaming process, is a highly porous one Metal foam layer forms.
  • the foamable metal body produced by the method according to the invention can be used to produce a porous metal body. This is done by heating the foamable body to a temperature above the decomposition temperature of the blowing agent, which releases the same gas, and then cooling the body so foamed. It is advantageous if the heating temperature is in the temperature range of the melting point of the metal used or above or in the solidus-liquidus interval of the alloy used.
  • the heating rates of the semi-finished product during the foaming process are within normal limits, i.e. they are about 1 - 5 ° C per sec. High heating rates are not necessary because the gas cannot escape anyway. These usual heating speeds are a further feature of the invention which leads to cost reduction. It goes without saying that in individual cases, e.g. to achieve small pore size, a high heating rate is advantageous.
  • the inventive method further provides that after the foaming, the cooling rate must be selected so that no further foaming takes place from the inside of the body. With larger parts, the cooling rate must be chosen higher than with smaller ones, it must be adapted to the sample volume.
  • a further advantageous embodiment of the method according to the invention provides that the density of the porous metal body can be varied by suitable selection of the foaming parameters time and temperature. If the foaming process is interrupted after a certain time at constant temperature, a certain density results. If the foaming process is continued for a longer period, this leads to different density values. It is important that certain limit values are observed: A maximum permissible foaming time, after which the already foamed material collapses, should be observed.
  • Foaming of the semi-finished product is free if no final shape is specified.
  • the foaming can also take place in a mold.
  • the finished porous metal body takes on the predetermined shape. It is therefore possible according to the method according to the invention to also produce molded parts from porous metallic material.
  • the metal body produced by foaming the semi-finished product obtained in this way has a predominantly closed porosity; the metal bodies float in the water.
  • the resulting pores are evenly distributed throughout the metal body, they are also approximately uniform in size.
  • the pore size can be adjusted during the foaming process by the time in which the metal foam can expand.
  • the density of the porous metal body can be adapted to the requirements. As already described, this can be done not only by a suitable choice of the foaming parameters, but also by a suitable addition of the blowing agent.
  • the strength and ductility of the porous metal body can be varied by selecting the parameters of temperature and time at which the foaming takes place. The two properties mentioned are influenced anyway by setting the desired pore size. It goes without saying that the properties of the finished metallic body depend above all on the choice of the starting materials.
  • the deformability of the compacted semi-finished product is comparable to that of the solid starting metal.
  • the semifinished product does not differ in appearance from that of the starting metal.
  • the semifinished product can therefore be processed into semifinished products of any geometry by known forming processes. It can be formed into sheets, profiles, etc. It can be used in almost any deformation process that takes the decomposition temperature into account. Only when the semi-finished product is heated to temperatures above the decomposition temperature of the blowing agent used does the foaming take place.
  • a body produced according to the embodiment according to claim 11 is used to produce a porous metal body, after the foaming, a slightly porous outer layer surrounds a core made of highly porous foamed metal.
  • Another use of the foamable body is the production of metal foams with a solid outer layer.
  • the foamable body first becomes a cylindrical one by suitable shaping processes Formed rod, which touches the walls in an initially freely expanding foam, the pores near the surface are flattened by the internal pressure of the material foaming from the inside, thus compressing the initially highly porous outer edge of the molded part.
  • the thickness of this outer edge which has an increased density in relation to the inside of the workpiece, can be controlled via the period of time in which after contact with the walls the material can foam further from the inside before the molded part is finally cooled, as a result of which the foaming is stopped.
  • the surface of the foamable body according to the invention or of the expanding foam is prevented by cooling from foaming as much as in the non-cooled areas.
  • the cooling can be effected by suitable cooling media or by contact with cold materials.
  • the cooling can act on the entire surface or only on partial areas.
  • Integral foam-like metal bodies can be produced by pasting a metal foam with identical or alien materials. In addition to gluing, other joining methods and fastening methods (soldering, welding, screwing) can also be used. Finally, a metal foam can also be cast with metal melts or other materials that are initially liquid and then solidify or harden.
  • a powder mixture of the composition AIMg1 with 0.2% by weight of titanium hydride was placed in a hot pressing device and heated to a temperature of 500 C under a pressure of 60 MPa. After a holding time of 30 minutes, the sample was relieved, removed and cooled. Foaming was carried out by heating the sample in a laboratory oven preheated to 800 ° C. The density of the resulting aluminum foam was approximately 0.55 g / cm 3 .
  • a powder mixture of the composition AIMg2 with 0.2 percent by weight titanium hydride was compacted in the hot pressing device under a pressure of 100 MPa and a temperature of 550 ° C. and relieved and removed after a holding time of 29 minutes.
  • the subsequent foaming of the sample was carried out by heating the sample in a laboratory oven preheated to 800 ° C. and resulted in a foam with a density of 0.6 g / cm 3.
  • a powder mixture of pure aluminum powder and 1.5 percent by weight sodium bicarbonate (NaHCOa) was placed in a hot press and heated to a temperature of 500 ° C. under a pressure of 150 MPa. After a holding time of 20 minutes, the sample was removed and foamed in an oven preheated to 850 C. The density of the resulting aluminum foam was 1.3 g / cm 3 .
  • a powder mixture of pure aluminum powder and 2 percent by weight aluminum hydroxide was filled into the hot press device and heated to a temperature of 500 ° C. under a pressure of 150 MPa. After a holding time of 25 minutes, the sample was removed and foamed in an oven preheated to 850 C. The density of the resulting aluminum foam was 0.8 g / cm3.
  • a bronze powder of the composition 60% Cu and 40% Sn was mixed with 1% by weight of titanium hydride powder and this powder mixture was compacted at a temperature of 500 C and a pressure of 100 MPa for 30 minutes. The compacted sample was then heated in an oven preheated to 800 C and thereby foamed. The resulting bronze foam had a density of about 1.4 g / cm 3 .
  • a mixture of 70 percent by weight copper powder and 30 percent by weight aluminum powder was mixed with 1 percent by weight titanium hydride and this powder mixture was compacted at a temperature of 500 ° C. and a pressure of 100 MPa for 20 minutes.
  • the compacted sample was then heated in an oven preheated to 950 C and thereby foamed.
  • the density of this foamed copper alloy was less than 1 g / c m 3.
  • a powder mixture of pure aluminum powder and 1.5 percent by weight sodium bicarbonate (NaHC0 3 ) was placed in a hot pressing device and heated to a temperature of 500 ° C. under a pressure of 150 MPa. After a holding time of 20 minutes, the sample was removed and foamed in an oven preheated to 850 C. The density of the resulting aluminum foam was 1.3 g / cm 3 .
  • a powder mixture of pure aluminum powder and 2 weight percent aluminum hydroxide was filled in the hot press device and heated to a temperature of 500 ° C. under a pressure of 150 MPa. After a holding time of 25 minutes, the sample was removed and foamed in an oven preheated to 850 C. The density of the resulting aluminum foam was 0.8 g / cm3.
  • a bronze powder of the composition 60% Cu and 40% Sn was mixed with 1% by weight of titanium hydride powder and this powder mixture was compacted at a temperature of 500 C and a pressure of 100 MPa for 30 minutes. The compacted sample was then heated in an oven preheated to 800 ° C. and thereby foamed. The resulting bronze foam had a density of about 1.4 g / cm 3 .
  • a mixture of 70% by weight copper powder and 30% by weight aluminum powder was mixed with 1% by weight titanium hydride and this powder mixture was compacted at a temperature of 500 ° C. and a pressure of 100 MPa for 20 minutes.
  • the compacted sample was then heated in an oven preheated to 950 ° C. and thereby foamed.
  • the density of this foamed copper alloy was less than 1 g / cm 3.
  • a powder mixture of aluminum powder and 0.4 weight percent titanium hydride powder was heated to a temperature of 350 ° C. This heated powder mixture was then fed into the roll gap and shaped into 3 passes. The result was a sheet which was cooled in still air. Sections measuring 100m x 100mm were cut out of this sheet, the edge areas with cracks being removed. The foaming of these sections was carried out freely in an oven preheated to 850 ° C. and led to density values of approximately 0.8 g / cm 3 . In a modification of the method, intermediate heating was carried out at 400 ° C. for 15 minutes after the first stitch. This intermediate heating largely reduced the occurrence of edge cracks.
  • a layer 2 of propellant-free metal powder is filled into a hot-pressing device 1, then a layer of propellant-containing metal powder 3 and finally again a layer 2 'of propellant-free metal powder.
  • a compact 4 is obtained, which can optionally be shaped into a further body 5. This body can then also be foamed into a body 6.
  • the blowing agent-free metal layers each form a firm, slightly porous bottom layer 7 or cover layer 8, between which there is a highly porous metal foam layer 9.
  • FIG. 2 Another method for producing integral foams is shown in FIG. 2.
  • the opening 19 of an extrusion tool 11 is initially covered by a disk made of solid metal piece 12.
  • the pressing chamber of the tool is filled with metal powder 13 containing blowing agent and the powder mixture is pressurized to about 60 MPa.
  • the latter is compacted by heating the tool together with the powder mixture 13.
  • the pressing pressure is increased so that the central area of the solid metal plate 12, which closes the opening 10 of the tool, flows through this opening 10 and thus releases it.
  • the foamable semi-finished product 14 is pressed together with the solid material 12 through the opening 10, the solid material 12 surrounding the foamable body in the form of an outer layer 13 closes.
  • a slightly porous layer surrounds a core made of highly porous foamed metal.
  • a metal powder 15 is mixed intensively with a blowing agent powder 16.
  • the mixture 17 thus obtained is compacted in a press 18 under the influence of pressure and temperature.
  • a semifinished product 19 is produced.
  • the semifinished product 19 can, for example, be formed into a sheet 20.
  • the sheet 20 can then be foamed to a finished porous metal body 21 by the action of temperature.

Abstract

A process for making foamed metal bodies is described, in which a mixture (17) of a metal powder (15) and a gas-evolving blowing agent powder (16) is thermocompacted to form a semi-finished product (19), at a temperature at which the bond of the metal powder particles predominantly takes place by diffusion and at a pressure which is high enough to prevent the decomposition of the blowing agent, in such a way that the metal particles are in a solid bond with one another and represent a gas-tight seal for the gas particles of the blowing agent. The foamable metal body may also be produced by rolling. Furthermore, use of the foamable metal body (19) thus produced for making a porous metal body (21) is proposed. <IMAGE>

Description

Die Erfindung betrifft Verfahren zur Herstellung aufschäumbarer Metallkörper und deren Verwendung.The invention relates to methods for producing foamable metal bodies and their use.

Aus der US-PS 3087807 ist ein Verfahren bekannt, nach dem die Herstellung eines porösen Metallkörpers beliebiger Form möglich ist. Danach wird eine Mischung aus einem Metallpulver und einem Treibmittelpulver mit einem Preßdruck von mindestens 80 MPa im ersten Schritt kalt kompaktiert. Durch anschließendes Strangpressen wird sie um mindestens 87,5% umgeformt. Dieser hohe Umformgrad ist notwendig, damit durch die Reibung der Teilchen aneinander während des Umformprozesses die Oxydhäute zerstört und die Metallteilchen miteinander verbunden werden. Der so hergestellte extrudierte Stab kann durch Erwärmung auf mindestens die Schmelztemperatur des Metalles zu einem porösen Metallkörper aufgeschäumt werden. Die Aufschäumung kann in verschiedenen Formen erfolgen, so daß der fertige poröse Metallkörper die gewünschte Form aufweist. Nachteilig ist, daß dieses Verfahren aufgrund seines zweistufigen Kompaktierungsvorganges sowie des erforderlichen, sehr hohen Umformgrades aufwendig und auf durch Strangpressen herstellbare Halbzeuge beschränkt ist. Bei dem in dieser US-PS offenbarten Verfahren sind nur Treibmittel verwendbar, deren Zersetzungstemperatur oberhalb der Kompaktierungstemperatur liegt, da sonst das Gas während des Aufheizvorganges entweichen würde. Gerade aber sind Treibmittel, deren Zersetzungstemperatur unterhalb der Kompaktierungstemperatur liegt, für viele Metallarten geeignet und preisgünstig. Während des auf den Kompaktierungsvorgang folgenden Aufschäumung entsteht ein poröser Metallkörper mit offener Porösität, wobei die Poren offen oder miteinander verbunden sind. Der Extrusionsvorgang nach dem in der US-PS beschriebenen Verfahren ist notwendig, da die Verbindung der Metallteilchen durch die bei dem Extrusionsvorgang auftretenden hohen Temperaturen und die Reibung der Teilchen aneinander, d.h. durch Verschweißung der Teilchen miteinander entsteht. Da aus obengenannten Gründen die für die Verbindung der Teilchen notwendige Tempemit sehr hohen Umformgraden gearbeitet werden, damit eine möglichst gute und gasdichte Verbindung der Metallteilchen untereinander entsteht.From US-PS 3087807 a method is known, according to which the production of a porous metal body of any shape is possible. A mixture of a metal powder and a blowing agent powder is then cold compacted with a compression pressure of at least 80 MPa in the first step. Subsequent extrusion then deforms it by at least 87.5%. This high degree of forming is necessary so that the oxide skins are destroyed and the metal particles are connected to one another by the friction of the particles against one another during the forming process. The extruded rod produced in this way can be foamed to a porous metal body by heating to at least the melting temperature of the metal. The foaming can take place in various forms, so that the finished porous metal body has the desired shape. It is disadvantageous that this method is complex due to its two-stage compacting process and the very high degree of deformation required and is limited to semi-finished products that can be produced by extrusion. Only blowing agents whose decomposition temperature is above the compacting temperature can be used in the process disclosed in this US Pat. No. otherwise the gas would escape during the heating process. However, blowing agents whose decomposition temperature is below the compacting temperature are particularly suitable and inexpensive for many types of metal. During the foaming following the compacting process, a porous metal body with open porosity is formed, the pores being open or connected to one another. The extrusion process according to the process described in the U.S. patent is necessary because the connection of the metal particles due to the high temperatures occurring during the extrusion process and the friction of the particles against one another, i.e. is created by welding the particles together. Since, for the reasons mentioned above, the temperatures required for the connection of the particles are worked with very high degrees of deformation, so that the metal particles are connected to one another as good and gas-tight as possible.

Daneben sind mehrere Verfahren bekannt, nach denen poröse Metallwerkstoffe hergestellt werden können. Eine einfache Methode zur Herstellung dieser Werkstoffe ist die Einmischung von gasabspaltenden Stoffen in Metallschmelzen. Durch die Temperatureinwirkung zersetzt sich das Treibmittel unter Freisetzung von Gas. Dieser Vorgang führt zur Aufschäumung der Metallschmelze. Nach Abschluß des Vorganges liegt ein aufgeschäumter Metallwerkstoff vor, welcher eine unregelmäßige, zufällige Form aufweist. Dieser Werkstoff kann durch entsprechende Verfahren zu Körpern gewünschter Form weiterverarbeitet werden. Es muß dabei jedoch beachtet werden, daß als Verfahren zur Weiterverarbeitung nur Trennverfahren in Frage kommen, und demnach nicht jeder beliebige Metallkörper aus einem solchen Metallwerkstoff geformt werden kann. Dies ist nachteilig. Mit ähnlichen Nachteilen sind auch weitere Verfahren zur Herstellung von porösen Metallwerkstoffen behaftet, wie z. B. Tränkung eines vorhandenen Kunststoffschaumstoffes mit einem Schlicker aus Metallpulver und einem Trägermedium und ein anschließendes Ausbrennen oder Verdampfen des Kunststoffschaumes nach erfolgter Trocknung. Diese Methode ist über die vorerwähnten Nachteile hinaus sehr aufwendig.In addition, several methods are known by which porous metal materials can be produced. A simple method for producing these materials is the mixing of gas-releasing substances in molten metals. The blowing agent decomposes with the release of gas due to the effect of temperature. This process leads to the foaming of the molten metal. After completion of the process, there is a foamed metal material which has an irregular, random shape. This material can be further processed into bodies of the desired shape by appropriate processes. However, it must be noted that only separation processes are suitable as processes for further processing, and consequently not every metal body can be formed from such a metal material. This is a disadvantage. Other processes for the production of porous metal materials also have similar disadvantages, such as, for. B. impregnation of an existing plastic foam with a slurry of metal powder and a carrier medium and a subsequent burning out or evaporation of the plastic foam after drying. In addition to the disadvantages mentioned above, this method is very complex.

Aufgabe der vorliegenden Erfindung ist es, ein Verfahren zur Herstellung aufschäumbarer Metallkörper anzugeben, welches preisgünstig, einfach in der Anwendung, ohne hohen umformtechnischen Aufwand durchführbar und gleichzeitig für Treibmittel mit niedriger Zersetzungstemperatur anwendbar ist. Eine weitere Aufgabe der Erfindung ist es, eine Verwendung der so hergestellten aufschäumbaren Körper vorzuschlagen.The object of the present invention is to provide a process for the production of foamable metal bodies which is inexpensive, simple to use, can be carried out without high forming outlay and at the same time can be used for blowing agents with a low decomposition temperature. Another object of the invention is to propose a use of the foamable bodies produced in this way.

Diese Aufgabe ist durch die in den Ansprüchen 1 und 6 und in dem Verwendungsanspruch angegebene Erfindung gelöst. Die Unteransprüche stellen vorteilhafte Weiterbildungen dar.This object is achieved by the invention specified in claims 1 and 6 and in the use claim. The subclaims represent advantageous developments.

Danach wird zunächst eine Mischung aus einem oder mehreren Metallpulvern und einem oder mehreren gasabspaltenden Treibmittelpulvern hergestellt. Als Treibmittel können Metallhydride, wie z.B. Titanhydrid, Karbonate, z.B.Calziumcarbonat, Kaliumcarbonat, Natriumcarbonat, Natriumbicarbonat, Hydrate, z. B. Aluminiumsulfathydrat, Alaun, Aluminiumhydroxid oder leicht verdampfende Stoffe, z.B. Quecksilberverbindungen oder pulverisierte organische Substanzen eingesetzt werden. Diese, intensiv durchmischte, Pulvermischung wird durch Heißpressen oder heißisostatisches Pressen zu einem kompakten, gasdichten Körper verdichtet. Bei dem Kompaktierungsvorgang ist erfindungsgemäß von ausschlaggebender Bedeutung, daß die Temperatur so hoch gewählt wird, daß die Verbindung zwischen den einzelnen Metallpulverteilchen überwiegend durch Diffusion erfolgt. Weiterhin ist es wesentlich, daß der Druck so hoch gewählt wird, daß die Zersetzung des Treibmittels verhindert wird und ein kompaktierter Körper entsteht, bei dem die Metallteilchen sich in einer festen Verbindung untereinander befinden und einen gasdichten Abschluß für die Gasteilchen des Treibmittels bilden. Die Treibmittelteilchen werden also zwischen den miteinander verbundenen Metallteilchen "eingeschlossen", so daß sie erst bei einem späteren Schritt des Aufschäumens Gas freisetzen. Somit können auch Treibmittel eingesetzt werden, deren Zersetzungstempatur unterhalb der Kompaktierungstemperatur liegt. Durch die Anwendung des hohen Druckes, zersetzen sich diese Treibmittel nicht. Diese erfindungsgemäße Maßnahme erlaubt den Einsatz von Treibmitteln, deren Auswahl nur nach den Gesichtspunkten der Verträglichkeit mit dem gewählten Metallpulver bzw. nach den Gesichtspunkten der Wirtschaftlichkeit des Verfahrens gewählt werden können. Durch die geeignete Wahl der Verfahrens-Parameter Temperatur und Druck wird erreicht, daß ein Körper entsteht, welcher eine gasdichte Struktur aufweist. Weiterhin wird dadurch, daß das Treibgas zwischen den Metallteilchen "eingeschlossen" bleibt, verhindert, daß es vorzeitig aus dem kompaktierten Körper entweicht. Demnach sind die erforderlichen Treibmittelmengen gering. So reichen Treibmittelanteile in der Größenordnung von wenigen Zehntel Gewichtsprozent aus, weil der kompaktierte Körper vollständig verdichtet ist und das Treibgas nicht entweichen kann. Als besonders günstig haben sich Treibmittelmengen von 0,2 bis 1% erwiesen.Es muß nur die Menge Treibmittel zugegeben werden, die zur Herstellung einer Schaumstruktur notwendig ist. Das führt zur Kostenersparnis. Weiterhin ist es vorteilhaft, daß , aufgrund der gewählten hohen Temperatur und der Anwendung des hohen Drukkes der Kompaktierungsvorgang in kurzer Zeit erfolgtThen a mixture of one or more metal powders and one or more gas-releasing blowing agent powders is first produced. Metal hydrides such as titanium hydride, carbonates, e.g. calcium carbonate, potassium carbonate, sodium carbonate, sodium bicarbonate, hydrates, e.g. B. aluminum sulfate hydrate, alum, aluminum hydroxide or easily evaporating substances, such as mercury compounds or powdered organic substances. This intensely mixed powder mixture is compressed by hot pressing or hot isostatic pressing into a compact, gas-tight body. In the compacting process, it is of crucial importance according to the invention that the temperature is selected so high that the connection between the individual metal powder particles is predominantly made by diffusion. It is also essential that the pressure is chosen so high that the decomposition of the propellant is prevented and a compact body is formed in which the metal particles are in a fixed connection with one another and form a gas-tight seal for the gas particles of the propellant. The blowing agent particles are thus "trapped" between the interconnected metal particles, so that they only release gas in a later step of foaming. So can also be used with blowing agents whose decomposition temperature is below the compacting temperature. By applying the high pressure, these blowing agents do not decompose. This measure according to the invention allows the use of blowing agents, the selection of which can only be chosen on the basis of compatibility with the selected metal powder or on the basis of the efficiency of the method. The suitable choice of the process parameters temperature and pressure ensures that a body is produced which has a gas-tight structure. Furthermore, the fact that the propellant gas remains “trapped” between the metal particles prevents it from escaping prematurely from the compacted body. Accordingly, the amounts of blowing agent required are small. Blowing agent proportions of the order of a few tenths of a percent by weight are sufficient because the compacted body is completely compressed and the propellant gas cannot escape. Amounts of blowing agent from 0.2 to 1% have proven to be particularly favorable. Only the amount of blowing agent that is necessary to produce a foam structure has to be added. This leads to cost savings. Furthermore, it is advantageous that, due to the selected high temperature and the application of the high pressure, the compacting process takes place in a short time

Ein vorteilhaftes Merkmal des erfindungsgemäßen Verfahrens ist, daß nach Beendigung des Heißkompktierungsvorganges sowohl die Wärmeeinwirkung als auch die Druckeinwirkung gleichzeitig aufgehoben werden. Der noch heiße Metallkörper behält seine Form, obwohl keine Druckeinwirkung mehr stattfindet. Das bedeutet, daß die Metallteilchen einen solchen dichten Abschluß für die Treibmittelpulverteilchen bilden, daß keine Expansion des Treibmittels, auch bei erhöhter Temperatur stattfindet. Der so hergestellte Metallkörper ist formstabil und behält seine Form auch unter erhöhter Temperatur und ohne Druckeinwirkung.An advantageous feature of the method according to the invention is that after the hot compaction process has ended, both the heat and the pressure are released simultaneously. The still hot metal body keeps its shape even though there is no longer any pressure. This means that the metal particles form such a tight seal for the blowing agent powder particles that there is no expansion of the blowing agent, even at elevated temperature. The metal body produced in this way is dimensionally stable and retains its shape even under elevated temperature and without the action of pressure.

Zur Festigkeitssteigerung der Metallkörper sieht die Erfindung die Zugabe von Verstärkungskomponenten in Form von Fasern oder Partikel aus geeigneten Materialien, wie z.B. Keramik vor. Diese werden vorteilhafterweise den Ausgangspulvern beigemischt. Dazu sollten insbesondere die Ausgangsmaterialien und die Aufschäumparameter so gewählt werden, daß eine gute Benetzung der Verstärkungskomponenten durch die Metallmatrix gewährleistet ist. Es ist vorteilhaft, wenn die Fasern bzw. Partikel beschichtet sind (z.B. mit Nickel). Dies gewährleistet, daß die Kräfte aus der Metallmatrix in die Partikel/Faser eingeleitet werden.To increase the strength of the metal body, the invention provides the addition of reinforcing components in the form of fibers or particles made of suitable materials, such as Ceramics before. These are advantageously added to the starting powders. For this purpose, the starting materials and the foaming parameters in particular should be selected so that a good wetting of the reinforcement components by the metal matrix is guaranteed. It is advantageous if the fibers or particles are coated (e.g. with nickel). This ensures that the forces from the metal matrix are introduced into the particle / fiber.

Ein weiteres Verfahren zur Herstellung aufschäumbarer Metallkörper ist das Walzen bei erhöhter Temperatur einer aus mindestens einem Metallpulver und mindestens einem Treibmittelpulver bestehenden Pulvermischung. Dabei entsteht eine Verbindung der Metall- und Treibmittelpulverteilchen im Walzspalt. Hierbei trifft für den Fachmann überraschend die Sonderheit zu, daß die Diffusion zwischen den Teilchen bereits bei niedrigeren Temperaturen, im Temperaturbereich um etwa 400 °C bei Aluminium in ausreichendem Maße auftritt. Diese Vorgänge treten insbesondere in den Oberflächenschichten auf. Als besonders vorteilhaft bei Aluminiumwalzen hat sich der Temperaturbereich zwischen 350 °C und 400 °C erwiesen. Insbesondere ist die Maßnahme einer Zwischenerwärmung des vorgewalzten Materials nach den einzelnen Walzstichen von Bedeutung, da dadurch das Entstehen von Kantenrissen weitgehend vermieden werden kann.Another method for producing foamable metal bodies is rolling at an elevated temperature of a powder mixture consisting of at least one metal powder and at least one blowing agent powder. This creates a connection between the metal and blowing agent powder particles in the roll gap. Surprisingly, the peculiarity of the person skilled in the art applies here that the diffusion between the particles occurs to a sufficient extent even at lower temperatures, in the temperature range around 400 ° C. for aluminum. These processes occur particularly in the surface layers. The temperature range between 350 ° C and 400 ° C has proven to be particularly advantageous with aluminum rollers. In particular, the measure of intermediate heating of the pre-rolled material after the individual roll passes is important, since this largely prevents the occurrence of edge cracks.

Gemäß einer Ausführungsform sieht das erfindungsgemäße Verfahren vor, daß sofern eine Ausrichtung der Verstärkung entlang einer Vorzugsrichtung vorliegen soll, diese durch Umformung des aufschäumbaren Körpers bewirkt werden kann. Diese Umformung kann z.B. durch Strangpressen oder Walzen erfolgen.According to one embodiment, the method according to the invention provides that if the reinforcement is to be aligned along a preferred direction, this can be brought about by reshaping the foamable body. This transformation can e.g. by extrusion or rolling.

In vorteilhafter Ausgestaltung sieht die Erfindung vor, daß zwei oder mehrere Treibmittel mit unterschiedlichen Zersetzungstemperaturen dem Metallpulver zugemischt werden. Wird ein aus dieser Pulvermischung hergestellter aufschäumbarer Körper erhitzt, so zersetzt sich zunächst das Treibmittel mit der niedrigeren Temperatur und bewirkt ein Aufschäumen. Wird die Temperatur weiter erhöht, zersetzt sich das Treibmittel mit der nächsthöherer Zersetzungstemperatur und bewirkt ein weiteres Aufschäumen. Das Aufschäumen erfolgt in zwei oder mehreren Stufen. Solche stufenweise expandierenden aufschäumbaren Metallkörper finden eine besondere Anwendung, z.B. im Brandschutz.In an advantageous embodiment, the invention provides that two or more blowing agents with different decomposition temperatures are mixed into the metal powder. If a foamable body produced from this powder mixture is heated, the blowing agent with the lower temperature first decomposes and causes foaming. If the temperature is increased further, the blowing agent decomposes at the next higher decomposition temperature and causes further foaming. The foaming takes place in two or more stages. Such gradually expanding foamable metal bodies have a particular application, e.g. in fire protection.

Ein besonderer Vorteil des erfindungsgemäßen Verfahrens besteht darin, daß es nun möglich ist, Körper herzustellen, welche über ihren Querschnitt eine sich kontinuierlich oder diskontinuierlich verändernde Dichte aufweisen, sogenannte gradierte Werkstoffe. Dabei wird eine Zunahme der Dichte zum Rand des aufschäumbaren Körpers hin bevorzugt, da hier die primäre Beanspruchung erfolgt. Weiterhin bietet ein aufschäumbarer Körper mit einer massiven Deckschicht oder einer Deckschicht höheren Dichte Vorteile hinsichtlich des Fügens und des Verbindens mit artgleichen oder artfremden Werkstoffen. Wird der Vorgang des Heißkompaktierens in einer Form durchgeführt, wobei die Pulvermischung ganz oder teilweise durch ein treibmittelfreies Metall oder Metallpulver umgeben ist, so bilden die treibmittelfreien Metallschichten fen. Wird der Vorgang des Heißkompaktierens in einer Form durchgeführt, wobei die Pulvermischung ganz oder teilweise durch ein treibmittelfreies Metall oder Metallpulver umgeben ist, so bilden die treibmittelfreien Metallschichten jeweils eine feste, wenig poröse Außenschicht bzw. Bodenschicht oder Deckschicht, zwischen denen sich eine Schicht befindet, welche nach einem Aufschäumvorgang eine hochporöse Metallschaumschicht bildet. Durch das Herstellen des aufschäumbaren Metallkörpers derart, daß der Pulvermischung ein treibmittelfreies Metallstück vorgelagert ist und die Pulvermischung stranggepreßt wird, entsteht ein aufschäumbarer Körper, der mit dem Massivmaterial zusammengepreßt ist und das Massivmaterial den aufschäumbaren Körper in Form einer äußeren Schicht umschließt.A particular advantage of the method according to the invention is that it is now possible to produce bodies which have a continuously or discontinuously changing density over their cross section, so-called graded materials. An increase in density toward the edge of the foamable body is preferred since this is where the primary stress occurs. Furthermore, a foamable body with a solid cover layer or a cover layer with a higher density offers advantages in terms of joining and joining with materials of the same or a different type. If the process of hot compacting is carried out in a mold, the powder mixture being wholly or partly surrounded by a metal or metal powder free of blowing agent, the blowing agent-free metal layers form fen. Will the process of hot compacting in carried out a form, the powder mixture being wholly or partially surrounded by a metal or metal powder free of blowing agent, the blowing agent-free metal layers each form a solid, less porous outer layer or bottom layer or cover layer, between which there is a layer which, after a foaming process, is a highly porous one Metal foam layer forms. By producing the foamable metal body in such a way that a piece of blowing agent-free metal is placed in front of the powder mixture and the powder mixture is extruded, a foamable body is formed which is pressed together with the solid material and the solid material encloses the foamable body in the form of an outer layer.

Der nach dem erfindungsgemäßen Verfahren hergestellte aufschäumbare Metallkörper kann zur Herstellung eines porösen Metallkörpers verwendet werden. Dies geschieht durch Aufheizen des aufschäumbaren Körpers auf eine Temperatur oberhalb der Zersetzungstempratur des Treibmittels, wobei derselbe Gas freisetzt, und anschließendes Abkühlen des so aufgeschäumten Körpers. Vorteilhaft ist, wenn die Aufheiztemperatur im Temperaturbereich des Schmelzpunktes des verwendeten Metalles liegt bzw. oberhalb oder im Solidus-Liquidus Intervall der verwendeten Legierung.The foamable metal body produced by the method according to the invention can be used to produce a porous metal body. This is done by heating the foamable body to a temperature above the decomposition temperature of the blowing agent, which releases the same gas, and then cooling the body so foamed. It is advantageous if the heating temperature is in the temperature range of the melting point of the metal used or above or in the solidus-liquidus interval of the alloy used.

Die Aufheizraten des Halbzeuges beim Aufschäumvorgang liegen in üblichen Grenzen, d.h. sie betragen etwa 1 - 5 ° C pro sec. Hohe Aufheizgeschwindigkeiten sind nicht notwendig, da das Gas ohnehin nicht entweichen kann. Diese üblichen Aufheizgeschwindigkeiten sind ein weiteres zur Kostensenkung führendes Merkmal der Erfindung. Selbstverständlich ist, daß in Einzelfällen, z.B. zur Erzielung kleiner Porengröße, eine hohe Aufheizgeschwindigkeit vorteilhaft ist.The heating rates of the semi-finished product during the foaming process are within normal limits, i.e. they are about 1 - 5 ° C per sec. High heating rates are not necessary because the gas cannot escape anyway. These usual heating speeds are a further feature of the invention which leads to cost reduction. It goes without saying that in individual cases, e.g. to achieve small pore size, a high heating rate is advantageous.

Das erfindungsgemäße Verfahren sieht weiterhin vor, daß nach dem Aufschäumen die Abkühlgeschwindigkeit so gewählt werden muß, daß kein weiterer Aufschäumvorgang vom Inneren des Körpers aus stattfindet. Bei größeren Teilen muß also die Abkühlgeschwindigkeit höher gewählt werden, als bei kleineren, sie muß dem Probenvolumen angepaßt sein.The inventive method further provides that after the foaming, the cooling rate must be selected so that no further foaming takes place from the inside of the body. With larger parts, the cooling rate must be chosen higher than with smaller ones, it must be adapted to the sample volume.

Eine weitere vorteilhafte Ausgestaltung des erfindungsgemäßen Verfahrens sieht vor, daß durch die geeignete Wahl der Aufschäumparameter Zeit und Temperatur die Dichte des porösen Metallkörpers variiert werden kann. Wird der Aufschäumvorgang nach einer bestimmten Zeit bei konstanter Temperatur unterbrochen, so ergibt sich eine bestimmte Dichte. Wird der Aufschäumvorgang länger fortgesetzt, so führt dies zu anderen Dichtewerten. Wichtig ist, daß bestimmte Grenzwerte beachtet werden: Eine maximal zulässige Aufschäumzeit, nach deren Überschreitung das bereits aufgeschäumte Material kollabiert, soll beachtet werden.A further advantageous embodiment of the method according to the invention provides that the density of the porous metal body can be varied by suitable selection of the foaming parameters time and temperature. If the foaming process is interrupted after a certain time at constant temperature, a certain density results. If the foaming process is continued for a longer period, this leads to different density values. It is important that certain limit values are observed: A maximum permissible foaming time, after which the already foamed material collapses, should be observed.

Das Aufschäumen des Halbzeuges erfolgt frei, wenn keine Endform vorgegeben ist. Das Aufschäumen kann auch in einer Form erfolgen. In diesem Fall nimmt der fertige poröse Metallkörper die vorgegebene Gestalt an. Es ist also nach dem erfindungsgemäßen Verfahren möglich, auch Formteile aus porösem metallischen Werkstoff herzustellen.Foaming of the semi-finished product is free if no final shape is specified. The foaming can also take place in a mold. In this case, the finished porous metal body takes on the predetermined shape. It is therefore possible according to the method according to the invention to also produce molded parts from porous metallic material.

Der durch das Aufschäumen des so beschaffenen Halbzeuges hergestellte Metallkörper weist eine überwiegend geschlossene Porösität auf; die Metallkörper schwimmen im Wasser. Die dabei entstehenden Poren sind gleichmäßig im gesamten Metallkörper verteilt, sie weisen auch eine annähernd einheitliche Größe auf. Die Porengröße kann während des Aufschäumvorganges durch die Zeit, in welcher der Metallschaum expandieren kann, eingestellt werden. Die Dichte des porösen Metallkörpers kann den Erfordernissen entsprechend angepaßt werden. Dies kann nicht nur, wie bereits beschrieben, durch die geeignete Wahl der Aufschäumparameter erfolgen, sondern auch durch eine geeignete Zugabe des Treibmittels. Durch die Wahl der Parameter Temperatur und Zeit, bei welchen das Aufschäumen erfolgt, kann die Festigkeit und die Duktilität des porösen Metallkörpers variiert werden. Die Beeinflussung der beiden genannten Eigenschaften geschieht ohnehin durch die Einstellung der erwünschten Porengröße. Selbstverständlich ist, daß die Eigenschaften des fertigen metallischen Körpers, vor allem von der Wahl der Ausgangsmaterialien abhängig sind.The metal body produced by foaming the semi-finished product obtained in this way has a predominantly closed porosity; the metal bodies float in the water. The resulting pores are evenly distributed throughout the metal body, they are also approximately uniform in size. The pore size can be adjusted during the foaming process by the time in which the metal foam can expand. The density of the porous metal body can be adapted to the requirements. As already described, this can be done not only by a suitable choice of the foaming parameters, but also by a suitable addition of the blowing agent. The strength and ductility of the porous metal body can be varied by selecting the parameters of temperature and time at which the foaming takes place. The two properties mentioned are influenced anyway by setting the desired pore size. It goes without saying that the properties of the finished metallic body depend above all on the choice of the starting materials.

Das Verformungsvermögen des kompaktierten Halbzeuges ist mit dem des massiven Ausgangsmetalles vergleichbar. Auch in seinem äußeren Aussehen unterscheidet sich das Halbzeug nicht von dem des Ausgangsmetalls. Das Halbzeug kann demnach durch bekannte Umformverfahren zu Halbzeugen beliebiger Geometrien verarbeitet werden. Es kann zu Blechen, Profilen etc. umgeformt werden. Es ist nahezu jedem Verformungsverfahren zugänglich, das unter Beachtung der Zersetzungstemperatur stattfindet. Erst beim auf den Umformvorgang stattfindenden Erwärmen des Halbzeuges auf Temperaturen oberhalb der Zersetzungstemperatur des verwendeten Treibmittels erfolgt das Aufschäumen.The deformability of the compacted semi-finished product is comparable to that of the solid starting metal. The semifinished product does not differ in appearance from that of the starting metal. The semifinished product can therefore be processed into semifinished products of any geometry by known forming processes. It can be formed into sheets, profiles, etc. It can be used in almost any deformation process that takes the decomposition temperature into account. Only when the semi-finished product is heated to temperatures above the decomposition temperature of the blowing agent used does the foaming take place.

Wird ein gemäß der Ausführungsform nach dem Anspruch 11 hergestellte Körper zur Herstellung eines porösen Metallkörpers verwendet, so umgibt nach dem Aufschäumen eine wenig poröse äußere Schicht einen Kern aus hochporösem geschäumten Metall. Eine weitere Verwendung des aufschäumbaren Körpers ist die Herstellung von Metallschäumen mit fester Außenschicht. Der aufschäumbare Körper wird dabei zunächst durch geeignete Umformverfahren zu einem zylindrischen Stab umgeformt, dieser in ein eines zunächst frei expandierenden Schaumes die Wandungen berührt, werden die oberflächennahen Poren durch den inneren Druck des von Innen nachschäumenden Materials flachgedrückt und so der zunächst hochporöse äußere Rand des Formteiles wieder verdichtet. Die Dicke dieses äußeren Randes, welche eine gegenüber dem Werkstükkinneren erhöhte Dichte besitzt, kann gesteuert werden über die Zeitdauer in welcher nach dem Kontakt mit den Wandungen das Material von Innen nachschäumen kann, bevor das Formteil schließlich abgekühlt wird, wodurch das Nachschäumen abgebrochen wird. Schließlich sind Verfahren möglich, bei denen die Oberfläche des erfindungsgemäßen aufschäumbaren Körpers oder des expandierenden Schaumes durch Kühlung daran gehindert wird, so stark wie in den nichtgekühlten Bereichen aufzuschäumen. Dabei kann die Kühlung durch geeignete Kühlmedien oder durch Kontakt mit kalten Materialien bewirkt werden. Die Kühlung kann auf die gesamte Oberfläche oder auch nur auf Teilbereiche einwirken.If a body produced according to the embodiment according to claim 11 is used to produce a porous metal body, after the foaming, a slightly porous outer layer surrounds a core made of highly porous foamed metal. Another use of the foamable body is the production of metal foams with a solid outer layer. The foamable body first becomes a cylindrical one by suitable shaping processes Formed rod, which touches the walls in an initially freely expanding foam, the pores near the surface are flattened by the internal pressure of the material foaming from the inside, thus compressing the initially highly porous outer edge of the molded part. The thickness of this outer edge, which has an increased density in relation to the inside of the workpiece, can be controlled via the period of time in which after contact with the walls the material can foam further from the inside before the molded part is finally cooled, as a result of which the foaming is stopped. Finally, methods are possible in which the surface of the foamable body according to the invention or of the expanding foam is prevented by cooling from foaming as much as in the non-cooled areas. The cooling can be effected by suitable cooling media or by contact with cold materials. The cooling can act on the entire surface or only on partial areas.

Integralschaumartige Metallkörper lassen sich durch Bekleben eines Metallschaumes mit artgleichen oder artfremden Werkstoffen herstellen. Neben dem Kleben sind auch andere Fügeverfahren und Befestigungsverfahren (Löten, Schweißen, Anschrauben) anwendbar. Schließlich kann ein Metallschaum auch mit Metallschmelzen oder anderen, zunächst flüssigen und dann erstarrenden oder erhärtenden Materialien umgossen werden.Integral foam-like metal bodies can be produced by pasting a metal foam with identical or alien materials. In addition to gluing, other joining methods and fastening methods (soldering, welding, screwing) can also be used. Finally, a metal foam can also be cast with metal melts or other materials that are initially liquid and then solidify or harden.

In den nachfolgenden Beispielen wird der Verlauf der erfindungsgemäßen Verfahren und einer Verwendung des nach dem erfindungsgemäßen Verfahren hergestellten aufschäumbaren Körper dargestellt:The course of the process according to the invention and the use of the foamable body produced by the process according to the invention is shown in the following examples:

Beispiel 1example 1

Eine Pulvermischung der Zusammensetzung AIMg1 mit 0,2 Gewichtsprozent Titanhydrid wurde in eine Heißpreßvorrichtung gefüllt und unter einem Druck von 60 MPa auf eine Temperatur von 500 C erwärmt. Nach einer Haltezeit von 30 Minuten wurde die Probe entlastet, ausgebaut und abgekühlt. Das Aufschäumen erfolgte durch Erwärmung der Probe in einem auf 800°C vorgeheizten Laborofen. Die Dichte des entstandenen Aluminiumschaumes lag bei ca. 0,55 g/cm3.A powder mixture of the composition AIMg1 with 0.2% by weight of titanium hydride was placed in a hot pressing device and heated to a temperature of 500 C under a pressure of 60 MPa. After a holding time of 30 minutes, the sample was relieved, removed and cooled. Foaming was carried out by heating the sample in a laboratory oven preheated to 800 ° C. The density of the resulting aluminum foam was approximately 0.55 g / cm 3 .

Beispiel 2:Example 2:

Eine Pulvermischung der Zusammensetzung AIMg2 mit 0,2 Gewichtsprozent Titanhydrid wurde in der Heißpreßvorrichtung unter einem Druck von 100 MPa und einer Temperatur von 550 C kompaktiert und nach einer Haltezeit von 29 Minuten entlastet und ausgebaut. Das anschließende Aufschäumen der Probe erfolgte durch Erwärmung der Probe in einem auf 800°C vorgeheizten Laborofen und führte zu einem Schaum der Dichte 0,6 g/cm3.A powder mixture of the composition AIMg2 with 0.2 percent by weight titanium hydride was compacted in the hot pressing device under a pressure of 100 MPa and a temperature of 550 ° C. and relieved and removed after a holding time of 29 minutes. The subsequent foaming of the sample was carried out by heating the sample in a laboratory oven preheated to 800 ° C. and resulted in a foam with a density of 0.6 g / cm 3.

Beispiel 3:Example 3:

Eine Pulvermischung aus Reinaluminiumpulver und 1,5 Gewichtsprozent Natriumbicarbonat (NaHCOa) wurde in eine Heißpreßvorrichtung gefüllt und unter einem Druck von 150 MPa auf eine Temperatur von 500° C erwärmt. Nach einer Haltezeit von 20 Minuten wurde die Probe ausgebaut und in einem auf 850 C vorgeheizten Ofen aufgeschäumt. Die Dichte des entstandenen Aluminiumschaums lag bei 1,3 g/cm3.A powder mixture of pure aluminum powder and 1.5 percent by weight sodium bicarbonate (NaHCOa) was placed in a hot press and heated to a temperature of 500 ° C. under a pressure of 150 MPa. After a holding time of 20 minutes, the sample was removed and foamed in an oven preheated to 850 C. The density of the resulting aluminum foam was 1.3 g / cm 3 .

Beispiel 4:Example 4:

Eine Pulvermischung aus Reinaluminiumpulver und 2 Gewichtsprozent Aluminiumhydroxid wurde in die Heißpreßvorrichtung gefüllt und unter einem Druck von 150 MPa auf eine Temperatur von 500. C erwärmt. Nach einer Haltezeit von 25 Minuten wurde die Probe ausgebaut und in einem auf 850 C vorgeheizten Ofen aufgeschäumt. Die Dichte des entstandenen Aluminiumschaums betrug 0,8 g/cm3.A powder mixture of pure aluminum powder and 2 percent by weight aluminum hydroxide was filled into the hot press device and heated to a temperature of 500 ° C. under a pressure of 150 MPa. After a holding time of 25 minutes, the sample was removed and foamed in an oven preheated to 850 C. The density of the resulting aluminum foam was 0.8 g / cm3.

Beispiel 5:Example 5:

Ein Bronzepulver der Zusammensetzung 60% Cu und 40% Sn wurde mit 1 Gewichtsprozent Titanhydridpulver vermischt und diese Pulvermischung bei einer Temperatur von 500 C und einem Druck von 100 MPa 30 Minuten lang kompaktiert. Anschließend wurde die kompaktierte Probe in einem auf 800 C vorgeheizten Ofen erwärmt und dadurch aufgeschäumt. Der resultierende Bronzeschaum hatte eine Dichte von etwa 1,4 g/cm3.A bronze powder of the composition 60% Cu and 40% Sn was mixed with 1% by weight of titanium hydride powder and this powder mixture was compacted at a temperature of 500 C and a pressure of 100 MPa for 30 minutes. The compacted sample was then heated in an oven preheated to 800 C and thereby foamed. The resulting bronze foam had a density of about 1.4 g / cm 3 .

Beispiel 6:Example 6:

Eine Mischung aus 70 Gewichtsprozent Kupferpulver und 30 Gewichtsprozent Aluminiumpulver wurde mit 1 Gewichtsprozent Titanhydrid vermischt und diese Pulvermischung bei einer Temperatur von 500°C und einem Druck von 100 MPa 20 Minuten lang kompaktiert. Anschließend wurde die kompaktierte Probe in einem auf 950 C vorgeheizten Ofen erwärmt und dadurch aufgeschäumt. Die Dichte dieser geschäumten Kupferlegierung lag unter 1 g/cm3.A mixture of 70 percent by weight copper powder and 30 percent by weight aluminum powder was mixed with 1 percent by weight titanium hydride and this powder mixture was compacted at a temperature of 500 ° C. and a pressure of 100 MPa for 20 minutes. The compacted sample was then heated in an oven preheated to 950 C and thereby foamed. The density of this foamed copper alloy was less than 1 g / c m 3.

Weitere Versuche zur Herstellung von Nickelschaum haben bereits zu ersten brauchbaren Ergebnissen geführt.Further attempts to produce nickel foam have already led to the first useful results.

Beispiel 3:Example 3:

Eine Pulvermischung aus Reinaluminiumpulver und 1,5 Gewichtsprozent Natriumbicarbonat (NaHC03) wurde in eine Heißpreßvorrichtung gefüllt und unter einem Druck von 150 MPa auf eine Temperatur von 500 °C erwärmt. Nach einer Haltezeit von 20 Minuten wurde die Probe ausgebaut und in einem auf 850 C vorgeheizten Ofen aufgeschäumt. Die Dichte des entstandenen Aluminiumschaums lag bei 1,3 g/cm3.A powder mixture of pure aluminum powder and 1.5 percent by weight sodium bicarbonate (NaHC0 3 ) was placed in a hot pressing device and heated to a temperature of 500 ° C. under a pressure of 150 MPa. After a holding time of 20 minutes, the sample was removed and foamed in an oven preheated to 850 C. The density of the resulting aluminum foam was 1.3 g / cm 3 .

Beispiel 4:Example 4:

Eine Pulvermischung aus Reinaluminiumpulver und 2 Gewichtsprozent Aluminiumhydroxid wurde in die Heißpreßvorrichtung gefüllt und unter einem Druck von 150 MPa auf eine Temperatur von 500°C erwärmt. Nach einer Haltezeit von 25 Minuten wurde die Probe ausgebaut und in einem auf 850 C vorgeheizten Ofen aufgeschäumt. Die Dichte des entstandenen Aluminiumschaums betrug 0,8 g/cm3.A powder mixture of pure aluminum powder and 2 weight percent aluminum hydroxide was filled in the hot press device and heated to a temperature of 500 ° C. under a pressure of 150 MPa. After a holding time of 25 minutes, the sample was removed and foamed in an oven preheated to 850 C. The density of the resulting aluminum foam was 0.8 g / cm3.

Beispiels 5:Example 5:

Ein Bronzepulver der Zusammensetzung 60% Cu und 40% Sn wurde mit 1 Gewichtsprozent Titanhydridpulver vermischt und diese Pulvermischung bei einer Temperatur von 500 C und einem Druck von 100 MPa 30 Minuten lang kompaktiert. Anschließend wurde die kompaktierte Probe in einem auf 800° C vorgeheizten Ofen erwärmt und dadurch aufgeschäumt. Der resultierende Bronzeschaum hatte eine Dichte von etwa 1,4 g/cm3.A bronze powder of the composition 60% Cu and 40% Sn was mixed with 1% by weight of titanium hydride powder and this powder mixture was compacted at a temperature of 500 C and a pressure of 100 MPa for 30 minutes. The compacted sample was then heated in an oven preheated to 800 ° C. and thereby foamed. The resulting bronze foam had a density of about 1.4 g / cm 3 .

Beispiel 6:Example 6:

Eine Mischung aus 70 Gewichtsprozent Kupferpulver und 30 Gewichtsprozent Aluminiumpulver wurde mit 1 Gewichtsprozent Titanhydrid vermischt und diese Pulvermischung bei einer Temperatur von 500 C und einem Druck von 100 MPa 20 Minuten lang kompaktiert. Anschließend wurde die kompaktierte Probe in einem auf 950 °C vorgeheizten Ofen erwärmt und dadurch aufgeschäumt. Die Dichte dieser geschäumten Kupferlegierung lag unter 1 g/cm3.A mixture of 70% by weight copper powder and 30% by weight aluminum powder was mixed with 1% by weight titanium hydride and this powder mixture was compacted at a temperature of 500 ° C. and a pressure of 100 MPa for 20 minutes. The compacted sample was then heated in an oven preheated to 950 ° C. and thereby foamed. The density of this foamed copper alloy was less than 1 g / cm 3.

Weitere Versuche zur Herstellung von Nickelschaum haben bereits zu ersten brauchbaren Ergebnissen geführt.Further attempts to produce nickel foam have already led to the first useful results.

Beispiel 7:Example 7:

Eine Pulvermischung aus Aluminiumpulver und 0,4 Gewichtsprozent Titanhydridpulver wurde auf eine Temperatur von 350°C erwärmt. Anschließend wurde diese erwärmte Pulvermischung dem Walzspalt zugeführt und in 3 Stichen umgeformt. Als Ergebnis lag ein Blech vor, welches an ruhender Luft abgekühlt wurde. Aus diesem Blech wurden Abschnitte der Abmessung 100m x 100mm herausgetrennt, wobei die rißbehafteten Randbereiche entfernt wurden. Das Aufschäumen dieser Abschnitte erfolgte frei in einem auf 850°C vorgewärmten Ofen und führte zu Dichtewerten von ca. 0,8 g/cm3. In einer Abwandlung des Verfahrens wurde nach dem ersten Stich eine Zwischenwärmung für 15 Minuten bei 400° C durchgeführt. Durch diese Zwischenwärmung konnte das Auftreten der Kantenrisse weitgehend reduziert werden.A powder mixture of aluminum powder and 0.4 weight percent titanium hydride powder was heated to a temperature of 350 ° C. This heated powder mixture was then fed into the roll gap and shaped into 3 passes. The result was a sheet which was cooled in still air. Sections measuring 100m x 100mm were cut out of this sheet, the edge areas with cracks being removed. The foaming of these sections was carried out freely in an oven preheated to 850 ° C. and led to density values of approximately 0.8 g / cm 3 . In a modification of the method, intermediate heating was carried out at 400 ° C. for 15 minutes after the first stitch. This intermediate heating largely reduced the occurrence of edge cracks.

Ein Ausführungsbeispiel des erfindungsgemäßen Verfahrens ist in den Figuren 1 und 2 dargestellt. Es zeigen:

  • Fig. 1 das Herstellen eines aufschäumbaren Integralmetallkörpers in einer Form;
  • Fig. 2 das Herstellungsverfahren eines aufschäumbaren Integralmetallkörpers durch Strangpressen;
  • Fig. 3 eine schematische Darstellung des erfindungsgemäßen Verfahrens und dessen Verwendung;
An embodiment of the method according to the invention is shown in Figures 1 and 2. Show it:
  • 1 shows the production of a foamable integral metal body in a mold;
  • Figure 2 shows the manufacturing process of a foamable integral metal body by extrusion.
  • 3 shows a schematic representation of the method according to the invention and its use;

Wie aus Fig. 1 ersichtlich, wird in eine Heißpreßvorrichtung 1 eine Schicht 2 aus treibmittelfreiem Metallpulver eingefüllt, anschließend eine Schicht aus treibmittelhaltigem Metallpulver 3 und schließlich wiederum eine Schicht 2' aus treibmittelfreiem Metallpulver. Nach Durchführung des erfindungsgemäßen Kompaktierungsverfahrens wird ein Preßling 4 erhalten, welcher gegebenenfalls zu einem weiteren Körper 5 umgeformt werden kann. Dieser Körper kann anschließend auch zu einem Körper 6 aufgeschäumt werden. Dabei bilden die treibmittelfreien Metallschichten jeweils eine feste, wenig poröse Bodenschicht 7 bzw. Deckschicht 8, zwischen denen sich eine hochporöse Metallschaumschicht 9 befindet.As can be seen from FIG. 1, a layer 2 of propellant-free metal powder is filled into a hot-pressing device 1, then a layer of propellant-containing metal powder 3 and finally again a layer 2 'of propellant-free metal powder. After the compacting method according to the invention has been carried out, a compact 4 is obtained, which can optionally be shaped into a further body 5. This body can then also be foamed into a body 6. The blowing agent-free metal layers each form a firm, slightly porous bottom layer 7 or cover layer 8, between which there is a highly porous metal foam layer 9.

Ein weiteres Verfahren zur Herstellung von Integralschäumen ist in Fig. 2 dargestellt. Hier wird die Öffnung 19 eines Strangpreßwerkzeuges 11 zunächst durch eine Scheibe aus massivem Metallstück 12 abgedeckt. Anschließend wird der Preßraum des Werkzeuges mit treibmittelhaltigem Metallpulver 13 gefüllt und die Pulvermischung unter einen Druck von etwa 60 MPa gesetzt. Durch Aufheizen des Werkzeuges mitsamt der Pulvermischung 13 wird die letztere verdichtet. Danach wird der Preßdruck so weit erhöht, daß der zentrale Bereich der Massivmetallplatte 12, welche die Öffnung 10 des Werkzeuges verschließt, durch diese Öffnung 10 hindurchfließt und diese so freigibt. Im weiteren Verlauf des Preßvorganges wird das aufschäumbare Halbzeug 14 gemeinsam mit dem Massivmaterial 12 durch die Öffnung 10 gepreßt, wobei das Massivmaterial 12 den aufschäumbaren Körper in Form einer äußeren Schicht 13 umschließt. Nach dem Aufschäumen dieses Verbundkörpers umgibt eine wenig poröse Schicht einen Kern aus hochporösem geschäumten Metall.Another method for producing integral foams is shown in FIG. 2. Here, the opening 19 of an extrusion tool 11 is initially covered by a disk made of solid metal piece 12. Then the pressing chamber of the tool is filled with metal powder 13 containing blowing agent and the powder mixture is pressurized to about 60 MPa. The latter is compacted by heating the tool together with the powder mixture 13. Thereafter, the pressing pressure is increased so that the central area of the solid metal plate 12, which closes the opening 10 of the tool, flows through this opening 10 and thus releases it. In the further course of the pressing process, the foamable semi-finished product 14 is pressed together with the solid material 12 through the opening 10, the solid material 12 surrounding the foamable body in the form of an outer layer 13 closes. After the foaming of this composite body, a slightly porous layer surrounds a core made of highly porous foamed metal.

In Fig. 3 ist eine schematische Darstellung des erfindungsgmäßen Verfahrens und eine Anwendung wiedergegeben: Ein Metallpulver 15 wird mit einem Treibmittelpulver 16 intensiv vermischt. Die so erhaltene Mischung 17 wird in einer Presse 18 unter Druck und Temperatureinfluß kompaktiert. Nach dem Kompaktieren entsteht ein Halbzeug 19. Das Halbzeug 19 kann beispielsweise zu einem Blech 20 umgeformt werden. Anschließend kann das Blech 20 durch Temperatureinwirkung zu einem fertigen porösen Metallkörper 21 aufgeschäumt werden.3 shows a schematic representation of the method and an application according to the invention: a metal powder 15 is mixed intensively with a blowing agent powder 16. The mixture 17 thus obtained is compacted in a press 18 under the influence of pressure and temperature. After compacting, a semifinished product 19 is produced. The semifinished product 19 can, for example, be formed into a sheet 20. The sheet 20 can then be foamed to a finished porous metal body 21 by the action of temperature.

Claims (16)

1. Verfahren zur Herstellung aufschäumbarer Metallkörper, bei dem eine Mischung aus mindestens einem Metallpulver und mindestens einem gasabspaltenden Treibmittelpulver hergestellt und zu einem Halbzeug heißkompaktiert wird, dadurch gekennzeichnet, daß die Heißkompaktierung bei einer Temperatur stattfindet, bei der die Verbindung der Metallpulverteilchen überwiegend durch Diffusion erfolgt und bei einem Druck, der hoch genug ist, um die Zersetzung des Treibmittels zu verhindern derart, daß die Metallteilchen sich in einer festen Verbindung untereinander befinden und einen gasdichten Abschluß für die Gasteilchen des Treibmittels darstellen.1. A process for the production of foamable metal bodies, in which a mixture of at least one metal powder and at least one gas-releasing blowing agent powder is produced and hot-compacted into a semi-finished product, characterized in that the hot compacting takes place at a temperature at which the connection of the metal powder particles takes place predominantly by diffusion and at a pressure high enough to prevent the decomposition of the blowing agent such that the metal particles are in a solid connection with one another and form a gas-tight seal for the gas particles of the blowing agent. 2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß die Temperatur beim Heißkompaktieren oberhalb der Zersetzungstemperatur des Treibmittels liegt.2. The method according to claim 1, characterized in that the temperature during hot compacting is above the decomposition temperature of the blowing agent. 3. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß nach Beendigung des Heißkompaktierungsvorganges die Wärmeeinwirkung und die Druckeinwirkung gleichzeitig aufgehoben werden und daß die vollständige Abkühlung des metallischen Körpers ohne Druckeinwirkung erfolgt.3. The method according to claim 1, characterized in that after the end of the hot compacting process, the heat and pressure are canceled simultaneously and that the complete cooling of the metallic body takes place without pressure. 4. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß der Pulvermischung Verstärkungskomponenten wie hochfeste Fasern, insbesondere auf keramischer Basis oder Keramikpartikel beigemischt sind.4. The method according to claim 1, characterized in that the powder mixture reinforcing components such as high-strength fibers, in particular based on ceramic or ceramic particles are added. 5. Verfahren nach Anspruch 4, dadurch gekennzeichnet, daß dem Schritt des Heißkompaktierens sich ein Verfahrensschritt anschließt, bei dem die Verstärkungskomponenten in einer Vorzugsrichtung ausgerichtet werden.5. The method according to claim 4, characterized in that the step of hot compacting is followed by a step in which the reinforcing components are aligned in a preferred direction. 6. Verfahren zur Herstellung aufschäumbarer Metallkörper bei dem eine Mischung aus mindestens einem Metallpulver und mindestens einem gasabspaltenden Treibmittelpulver hergestellt wird, dadurch gekennzeichnet, daß diese Mischung gewalzt wird, bei erhöhter Temperatur und bei einem Druck, der hoch genug ist, um die Zersetzung des Treibmittels zu verhindern derart, daß die Metallteilchen sich in einer festen Verbindung untereinander befinden und einen gasdichten Abschluß für die Gasteilchen des Treibmittels darstellen.6. A process for the production of foamable metal bodies in which a mixture of at least one metal powder and at least one gas-releasing blowing agent powder is produced, characterized in that this mixture is rolled at elevated temperature and at a pressure which is high enough to decompose the blowing agent to prevent such that the metal particles are in a solid connection with each other and represent a gas-tight seal for the gas particles of the blowing agent. 7. Verfahren nach Anspruch 6, dadurch gekennzeichnet, daß die Walztemperatur 3500 c-400 C bei Materialien Aluminium und Titanhydrid beträgt.7. The method according to claim 6, characterized in that the rolling temperature is 3500 c-400 C for materials aluminum and titanium hydride. 8. Verfahren nach Anspruch 7, dadurch gekennzeichnet, daß nach einzelnen Walzstichen das vorgewalzte Halbzeug zwischenerwärmt wird.8. The method according to claim 7, characterized in that the pre-rolled semi-finished product is reheated after individual rolling passes. 9. Verfahren nach Anspruch 6, dadurch gekennzeichnet, daß die Temperatur der Zwischenerwärmung 400 C beträgt und die Zeitdauer 15 Minuten.9. The method according to claim 6, characterized in that the temperature of the intermediate heating is 400 C and the time period is 15 minutes. 10. Verfahren nach einem oder mehreren der vorangegangenen Ansprüche, dadurch gekennzeichnet, daß mindestens zwei Treibmittelpulver mit unterschiedlichen Zersetzungstemperaturen verwendet werden.10. The method according to one or more of the preceding claims, characterized in that at least two blowing agent powders with different decomposition temperatures are used. 11. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß das Heißkompaktieren in einer Form erfolgt, wobei die Pulvermischung ganz oder teilweise durch ein treibmittelfreies Metall oder Metallpulver umgeben ist.11. The method according to claim 1, characterized in that the hot compacting takes place in a mold, the powder mixture being wholly or partly surrounded by a blowing agent-free metal or metal powder. 12. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß das Heißkompaktieren durch Strangpressen erfolgt, wobei der Pulvermischung ein treibmittelfreies Metallstück vorgelagert ist.12. The method according to claim 1, characterized in that the hot compacting is carried out by extrusion, the powder mixture being preceded by a blowing agent-free piece of metal. 13. Verwendung des im Verfahren nach einem oder mehreren der vorangegangenen Ansprüche hergestellten metallischen Körpers zur Herstellung eines porösen Metallkörpers durch Aufheizen auf eine Temperatur oberhalb der Zersetzungstemperatur des Treibmittels und anschließendes Abkühlen des so aufgeschäumten Körpers.13. Use of the metallic body produced in the process according to one or more of the preceding claims for producing a porous metal body by heating to a temperature above the decomposition temperature of the blowing agent and then cooling the body thus foamed. 14. Verwendung des im Verfahren nach einem oder mehreren der vorangegangenen Ansprüche 1 bis 12 hergestellten metallischen Körpers zur Herstellung eines porösen Metallkörpers durch Aufheizen auf eine Temperatur oberhalb der Zersetzungstemperatur des Treibmittels im Temperaturbereich des Schmelzpunktes des verwendeten Metalles bzw. im Solidus-Liquidus Intervall der verwendeten Legierung und anschließendes Abkühlen des so aufgeschäumten Körpers.14. Use of the metallic body produced in the process according to one or more of the preceding claims 1 to 12 for producing a porous metal body pers by heating to a temperature above the decomposition temperature of the blowing agent in the temperature range of the melting point of the metal used or in the solidus-liquidus interval of the alloy used and then cooling the body thus foamed. 15. Verwendung des im Verfahren nach einem oder mehreren der vorangegangenen Ansprüche 1 bis 12 hergestellten metallischen Körpers zur Herstellung eines porösen Metallkörpers durch Aufheizen auf eine Temperatur oberhalb der Zersetzungstemperatur des Treibmittels, wobei beim Aufschäumen des metallischen Körpers unterschiedliche Temperatur- und Zeitwerte in Abhängigkeit von der zu erreichenden Dichte des herzustellenden Metallkörpers eingestellt sind und anschließendes Abkühlen des so aufgeschäumten Körpers.15. Use of the metallic body produced in the process according to one or more of the preceding claims 1 to 12 for the production of a porous metal body by heating to a temperature above the decomposition temperature of the blowing agent, with different temperature and time values depending on the foaming of the metallic body to be achieved density of the metal body to be produced are set and then cooling of the foamed body. 16. Verwendung des im Verfahren nach einem oder mehreren der vorangegangenen Ansprüche 1 bis 12 hergestellten metallischen Körpers zur Herstellung eines porösen Metallkörpers durch Aufheizen auf eine Temperatur oberhalb der Zersetzungstemperatur des Treibmittels, wobei die Aufheizgeschwindigkeit zwischen 1 und 5°C/sec beträgt und anschließendes Abkühlen des so aufgeschäumten Körpers mit einer Geschwindigkeit, die im Verhältnis zum Volumen des aufgeschäumten Körpers derart hoch ist, daß weiteres Aufschäumen abgebrochen wird.16. Use of the metallic body produced in the process according to one or more of the preceding claims 1 to 12 for the production of a porous metal body by heating to a temperature above the decomposition temperature of the blowing agent, the heating rate being between 1 and 5 ° C./sec and subsequent cooling of the body so foamed at a speed which is so high in relation to the volume of the foamed body that further foaming is stopped.
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Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1993025718A1 (en) * 1992-06-09 1993-12-23 Matec Holding Ag Process for making mouldings and use thereof
FR2742856A1 (en) * 1995-12-21 1997-06-27 Renault Automobile heat exchanger with permeable three-dimensional linked lattice structure
EP0804982A2 (en) * 1996-04-19 1997-11-05 Leichtmetallguss-Kokillenbau-Werk Illichmann GmbH Process for preparing metal foam parts
EP0868956A1 (en) * 1997-02-28 1998-10-07 Machner &amp; Saurer GmbH Process for preparing metal articles with internal porosity
EP0927591A2 (en) * 1998-01-02 1999-07-07 Wilhelm Karmann GmbH Process for forming a workpiece with a metal foam layer
WO1999052661A1 (en) * 1998-04-09 1999-10-21 Mepura Metallpulvergesellschaft Mbh Ranshofen Method for producing forms and foamed metal forms
WO1999064287A1 (en) * 1998-06-09 1999-12-16 M.I.M. Hüttenwerke Duisburg Gmbh Method for reinforcing a cavity of a motor vehicle structural member
EP1008406A2 (en) * 1998-12-09 2000-06-14 Bayerische Motoren Werke Aktiengesellschaft Method for the production of a hollow article filled with a light-metal foam structure
DE19908867A1 (en) * 1999-03-01 2000-09-07 Arved Huebler Composite body useful in machine construction comprises metal foam and solid parts joined together by a metallurgical bond of fused adjoining material layers
NL1016713C2 (en) * 2000-11-27 2002-05-29 Stork Screens Bv Heat exchanger and such a heat exchanger comprising thermo-acoustic conversion device.
DE19717894B4 (en) * 1996-05-02 2005-06-23 Mepura Metallpulvergesellschaft M.B.H. Process for the production of porous matrix materials, in particular moldings based on metals, and semi-finished products therefor
WO2007101799A2 (en) * 2006-03-03 2007-09-13 Deutsches Zentrum für Luft- und Raumfahrt e.V. Composite metal-aerogel material
WO2007128374A1 (en) * 2006-05-04 2007-11-15 Alulight International Gmbh Method for production of composite bodies and composite bodies produced thereby
EP2295390A1 (en) 2009-09-04 2011-03-16 Manfred Jaeckel Method for producing a cellular sinter mould
WO2011151193A1 (en) * 2010-05-31 2011-12-08 Siemens Aktiengesellschaft Method for generating a closed-pore metal foam and component which has a closed-pore metal foam
WO2018130550A1 (en) * 2017-01-12 2018-07-19 Lisa Dräxlmaier GmbH Vehicle component with foamed electrical conductive structure and manufacturing method for such a component

Families Citing this family (97)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4206303C1 (en) * 1992-02-28 1993-06-17 Mepura Metallpulver Ges.M.B.H., Ranshofen, At
DE4424157C2 (en) * 1993-07-29 1996-08-14 Fraunhofer Ges Forschung Process for the production of porous metallic materials with anisotropic thermal and electrical conductivities
DE4426627C2 (en) * 1993-07-29 1997-09-25 Fraunhofer Ges Forschung Process for the production of a metallic composite material
DE19651197C2 (en) * 1995-12-15 1999-10-28 Susan Dietzschold Material for producing porous metal bodies
DE19612781C1 (en) * 1996-03-29 1997-08-21 Karmann Gmbh W Component made of metallic foam material, process for final shaping of this component and device for carrying out the process
DE19734394C2 (en) * 1996-08-13 2003-06-18 Friedrich Wilhelm Bessel Inst Method and device for producing metal foam
DE19709672C2 (en) * 1997-03-11 1998-12-24 Koenig & Bauer Albert Ag Cylinders for printing machines
DE19717066C1 (en) * 1997-04-23 1998-02-26 Daimler Benz Ag Local injections of structural aluminium- or plastic foam into anticipated separation points
ES2193439T3 (en) * 1997-06-10 2003-11-01 Goldschmidt Ag Th FOAM METAL BODY.
ES2167938T3 (en) * 1997-08-30 2002-05-16 Honsel Gmbh & Co Kg ALLOY FOR THE MANUFACTURE OF METAL FOAM BODIES BY THE USE OF A DUST WITH GERMAN TRAINING ADDITIVES.
DE19746164B4 (en) * 1997-10-18 2005-09-15 Volkswagen Ag Composite material with an at least partially hollow profile and use thereof
DE19813176C2 (en) * 1998-03-25 2000-08-24 Fraunhofer Ges Forschung Process for the production of composite parts
DE19813554A1 (en) * 1998-03-27 1999-09-30 Vaw Ver Aluminium Werke Ag Composite sheet or strip in sandwich structure and process for its production
JP3508604B2 (en) * 1998-04-08 2004-03-22 三菱マテリアル株式会社 Method for producing high-strength sponge-like fired metal composite plate
CA2339558A1 (en) * 1998-08-06 2000-02-17 The Boc Group Plc Hydrostatic pressure retainment system
US6168072B1 (en) * 1998-10-21 2001-01-02 The Boeing Company Expansion agent assisted diffusion bonding
DE19849600C1 (en) * 1998-10-28 2001-02-22 Schunk Sintermetalltechnik Gmb Process for the production of a metallic composite
DE19852277C2 (en) * 1998-11-13 2000-12-14 Schunk Sintermetalltechnik Gmb Process for the production of a metallic composite material and semi-finished product for such
DE19854175C1 (en) * 1998-11-24 2000-03-23 Fritz Michael Streuber Metal foam process for joining components having variety of shapes involves using shell-like clamp which bounds a space and accommodates foamable metal material producing a joint in the form of compound component
DE19854173C2 (en) * 1998-11-24 2000-11-23 Fritz Michael Streuber Metal foam molded body
GB9903276D0 (en) * 1999-02-12 1999-04-07 Boc Group Plc Reticulated foam structutes
DE19907855C1 (en) * 1999-02-24 2000-09-21 Goldschmidt Ag Th Manufacture of metal foams
US6698331B1 (en) 1999-03-10 2004-03-02 Fraunhofer Usa, Inc. Use of metal foams in armor systems
ATE256853T1 (en) 1999-03-10 2004-01-15 Fraunhofer Ges Forschung USE OF METAL FOAM IN ARMOR SYSTEMS
RU2154548C1 (en) * 1999-03-18 2000-08-20 Арбузова Лариса Алексеевна Method of producing porous semifinished and finished products from powders of aluminum alloys (versions)
DE19919574A1 (en) * 1999-04-29 2000-11-30 Lucas Ind Plc Piston and method of making the same
EP1196259B1 (en) 1999-05-19 2002-12-04 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Component comprised of a composite material containing a formable metallic material and method for producing the same
GB9912215D0 (en) * 1999-05-26 1999-07-28 Boc Group Plc Reticulated foam structures
DE19930982C1 (en) * 1999-07-05 2001-03-08 Honsel Ag Process for producing composite sheets by rolling
RU2193948C2 (en) * 1999-07-06 2002-12-10 Лебедев Виктор Иванович Method for making porous metal and articles of such metal
DE19933870C1 (en) * 1999-07-23 2001-02-22 Schunk Sintermetalltechnik Gmb Composite body used in vehicle construction has a foamed metal material e.g. aluminum foam surrounding a reinforcement
DE19941278A1 (en) * 1999-08-31 2001-03-08 Bernd Fischer Structure dissipating and absorbing mechanical energy for protection in e.g. vehicle crash comprises casing supported by bound, tightly-packed porous granules which both absorbs and dissipates impact
DE19942916A1 (en) 1999-09-08 2001-03-15 Linde Gas Ag Manufacture of foamable metal bodies and metal foams
US6481911B1 (en) 1999-11-24 2002-11-19 Fritz Michael Streuber Jointing method for joining preformed bodies
US6605368B2 (en) 1999-12-21 2003-08-12 Laura Lisa Smith Cookware vessel
NL1014116C2 (en) * 2000-01-19 2001-07-20 Corus Aluminium Walzprod Gmbh Method and device for forming a laminate of compressed metal powder with a foaming agent between two metal layers, and product formed therewith.
DE10024776C1 (en) 2000-05-19 2001-09-06 Goldschmidt Ag Th Zinc treated with metal hydride is used in organometallic synthesis, especially synthesis of cyclopropane derivatives and zinc organyl compounds and in Reformatsky and analogous reactions
US6464933B1 (en) * 2000-06-29 2002-10-15 Ford Global Technologies, Inc. Forming metal foam structures
DE10045494C2 (en) * 2000-09-13 2002-07-18 Neue Materialien Fuerth Gmbh Process for producing a shaped body from metal foam
DE10049058B4 (en) * 2000-10-04 2005-07-28 Honsel Gmbh & Co Kg Making welded joints between metal strips, plates, ingots and / or profiles
CA2344088A1 (en) * 2001-01-16 2002-07-16 Unknown A method and an apparatus for production of a foam metal
US6524522B2 (en) 2001-03-07 2003-02-25 Advanced Ceramics Research, Inc. Method for preparation of metallic foam products and products made
US6852272B2 (en) * 2001-03-07 2005-02-08 Advanced Ceramics Research, Inc. Method for preparation of metallic and ceramic foam products and products made
DE10127716A1 (en) * 2001-06-07 2002-12-12 Goldschmidt Ag Th Production of metal/metal foam composite components comprises inserting a flat or molded metal part into the hollow chamber of a casting mold, inserting a mixture of molten metal
RU2200647C1 (en) * 2001-07-17 2003-03-20 Литвинцев Александр Иванович Method for making porous semifinished products of aluminium alloy powders
DE10136370B4 (en) * 2001-07-26 2005-03-31 Schwingel, Dirk, Dr. Composite material and component made therefrom consisting of a foamed metal core and solid cover sheets, and method for the production
US6808003B2 (en) * 2001-08-07 2004-10-26 Alcoa Inc. Coextruded products of aluminum foam and skin material
US6660224B2 (en) * 2001-08-16 2003-12-09 National Research Council Of Canada Method of making open cell material
US7108828B2 (en) * 2001-08-27 2006-09-19 National Research Council Of Canada Method of making open cell material
US6689509B2 (en) * 2001-09-20 2004-02-10 Daramic, Inc. Laminated multilayer separator for lead-acid batteries
DE10161348A1 (en) * 2001-12-13 2003-06-26 Trw Automotive Safety Sys Gmbh vehicle steering wheel
JP3805694B2 (en) 2002-02-15 2006-08-02 本田技研工業株式会社 Method for producing foam / porous metal
DE10215086B4 (en) * 2002-02-18 2004-01-29 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Foamable metal body, process for its production and its use
US20040126583A1 (en) * 2002-11-19 2004-07-01 Takashi Nakamura Foaming agent for manufacturing a foamed or porous metal
JP4233018B2 (en) * 2003-01-17 2009-03-04 本田技研工業株式会社 Manufacturing method of closed cross-section structure filled with foam
AT6727U1 (en) * 2003-01-30 2004-03-25 Plansee Ag METHOD FOR PRODUCING POROUS SINTERED BODIES
EP1468765A1 (en) * 2003-04-16 2004-10-20 Corus Technology BV Preform for foamed sheet product and foamed product manufactured therefrom
US7516529B2 (en) * 2003-12-17 2009-04-14 General Motors Corporation Method for producing in situ metallic foam components
DE10359502A1 (en) * 2003-12-18 2005-07-14 Bayerische Motoren Werke Ag Production of a three-dimensional flat component used as part of a car chassis comprises deforming a board having a foamed core layer to form the three-dimensional component
US7481968B2 (en) 2004-03-17 2009-01-27 National Institute Of Advanced Industrial Science And Technology Method for preparing a sintered porous body of metal or ceramic
US7597840B2 (en) 2005-01-21 2009-10-06 California Institute Of Technology Production of amorphous metallic foam by powder consolidation
US20060269434A1 (en) * 2005-05-31 2006-11-30 Ecer Gunes M Process for porous materials and property improvement methods for the same
DE102005037305B4 (en) * 2005-08-02 2007-05-16 Hahn Meitner Inst Berlin Gmbh Process for the powder metallurgy production of metal foam and parts made of metal foam
DE102005037069B4 (en) * 2005-08-05 2010-03-18 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Porous composites based on a metal and process for their preparation
US20070154731A1 (en) * 2005-12-29 2007-07-05 Serguei Vatchiants Aluminum-based composite materials and methods of preparation thereof
DE102006018381A1 (en) * 2006-04-20 2007-10-25 Siemens Ag Process for increasing the stiffness of a metal component at least in sections with a hollow space accessible from the outside useful in metal processing avoids the high cost and possible component damage of previous processes
AT504305B1 (en) * 2006-10-05 2009-09-15 H Tte Klein Reichenbach Ges M MULTILAYER METAL MOLDING PENCIL WITH A METAL FOAM MATRIX AND ITS USE
US20090326657A1 (en) * 2008-06-25 2009-12-31 Alexander Grinberg Pliable Artificial Disc Endplate
KR101111286B1 (en) * 2008-08-22 2012-03-14 한국생산기술연구원 manufacturing method of foaming metal using a foam body
DE102008044946B4 (en) * 2008-08-29 2022-06-15 Evonik Superabsorber Gmbh Use of foam bodies in oxidation reactors for the production of unsaturated carboxylic acids
JP5402380B2 (en) * 2009-03-30 2014-01-29 三菱マテリアル株式会社 Method for producing porous aluminum sintered body
CN102438778B (en) 2009-03-30 2014-10-29 三菱综合材料株式会社 Process for producing porous sintered aluminum, and porous sintered aluminum
JP5492191B2 (en) 2009-03-30 2014-05-14 株式会社トクヤマ Method for manufacturing metallized substrate, metallized substrate
JP5428546B2 (en) * 2009-06-04 2014-02-26 三菱マテリアル株式会社 Method for producing aluminum composite having porous aluminum sintered body
JP5402381B2 (en) * 2009-08-11 2014-01-29 三菱マテリアル株式会社 Method for producing porous aluminum sintered body
US8820610B2 (en) 2009-10-14 2014-09-02 National University Corporation Gunma University Using friction stir processing to form foamed metal precursors
EP2544515A4 (en) * 2010-03-02 2014-07-30 Tokuyama Corp Method for manufacturing a metallized substrate
IT1399822B1 (en) * 2010-03-23 2013-05-03 Matteazzi METHOD TO OBTAIN POROUS SYSTEMS
DE102010022599B3 (en) * 2010-05-31 2011-12-01 Siemens Aktiengesellschaft Producing a closed-porous metal foam, comprises subjecting a composite made of metal/metal alloy and propellant to a heat treatment, where the heating of the composite is sufficient, so that propellant forms propellant gas
FR2961894B1 (en) * 2010-06-24 2013-09-13 Valeo Vision HEAT EXCHANGE DEVICE, IN PARTICULAR FOR A MOTOR VEHICLE
JP5720189B2 (en) * 2010-11-10 2015-05-20 三菱マテリアル株式会社 Porous implant material
JP2012100846A (en) * 2010-11-10 2012-05-31 Mitsubishi Materials Corp Porous implant material
UA112633C2 (en) * 2013-01-28 2016-10-10 Андрій Євгенійович Малашко A METHOD OF MANUFACTURING THE WORKING AUTHORITY OF THE TECHNOLOGICAL EQUIPMENT WITH A Wear-resistant element that interacts with the abrasive medium
WO2015006381A2 (en) 2013-07-08 2015-01-15 Loukus Adam R Core structured components and containers
JP5825311B2 (en) * 2013-09-06 2015-12-02 三菱マテリアル株式会社 Aluminum porous sintered body
CN106575591B (en) * 2014-08-06 2019-12-06 西门子公司 Electrical safety device with metal foam and method for interrupting current through an electrical safety device
DE102015205829B4 (en) * 2015-03-31 2017-01-05 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Process for producing foamed sandwich elements
EP3121659B1 (en) * 2015-07-24 2018-06-06 The Swatch Group Research and Development Ltd. Assembly of a part made of fragile material
US10590529B2 (en) * 2015-11-20 2020-03-17 Fourté International, Sdn. Bhd Metal foams and methods of manufacture
WO2017097512A1 (en) * 2015-12-07 2017-06-15 Dynaenergetics Gmbh & Co. Kg Shaped charge metal foam package
CN105642898B (en) * 2016-01-14 2017-07-25 哈尔滨工程大学 A kind of method that use laser 3D printing technology manufactures closed pore structures material
EP3548549B1 (en) 2016-12-02 2023-05-10 Safran Openly porous acoustic foam, process for manufacture and uses thereof
CN106862572A (en) * 2017-01-24 2017-06-20 东莞市佳乾新材料科技有限公司 A kind of antiknock aluminium foam sandwich plate for building and preparation method thereof
DE102017121513A1 (en) * 2017-09-15 2019-03-21 Pohltec Metalfoam Gmbh Process for foaming metal in the liquid bath
WO2019152918A1 (en) 2018-02-02 2019-08-08 Santeri Holdings LLC Identifiable physical form, sales instruments, and information marketplace for commodity trades
DE102021126310A1 (en) 2021-10-11 2023-04-13 HAVEL metal foam GmbH Method and device for producing a foamable, band-shaped pressed powder metal blank by means of cold rolling and pressed powder metal blank
CN114939674B (en) * 2022-05-06 2024-04-05 上海汉邦联航激光科技有限公司 Selective laser melting forming method of multi-porosity foam copper

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3087807A (en) * 1959-12-04 1963-04-30 United Aircraft Corp Method of making foamed metal
GB939612A (en) * 1960-02-04 1963-10-16 Dow Chemical Co Shaped metal and process for its production

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3848666A (en) * 1970-11-19 1974-11-19 Ethyl Corp Foamed metal bodies
US3941182A (en) * 1971-10-29 1976-03-02 Johan Bjorksten Continuous process for preparing unidirectionally reinforced metal foam
US3940262A (en) * 1972-03-16 1976-02-24 Ethyl Corporation Reinforced foamed metal
US3929425A (en) * 1973-02-26 1975-12-30 Ethyl Corp Foamed metal bodies
JPS57185902A (en) * 1981-05-11 1982-11-16 Nippon Seiko Kk Sintering method for porous body
JPS60149739A (en) * 1984-08-06 1985-08-07 Res Inst Iron Steel Tohoku Univ Production of composite nickel material reinforced with silicon carbide fiber
JPH01298123A (en) * 1988-05-27 1989-12-01 Sumitomo Electric Ind Ltd Manufacture of porous aluminum alloy
JPH0617524B2 (en) * 1988-11-08 1994-03-09 勝廣 西山 Magnesium-titanium sintered alloy and method for producing the same
US4973358A (en) * 1989-09-06 1990-11-27 Alcan International Limited Method of producing lightweight foamed metal

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3087807A (en) * 1959-12-04 1963-04-30 United Aircraft Corp Method of making foamed metal
GB939612A (en) * 1960-02-04 1963-10-16 Dow Chemical Co Shaped metal and process for its production

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
WORLD PATENT INDEX, FILE SUPPLIER Zusamenfassung AN=85-163640 Derwent Publications Ltd., London, GB & SU-A-1 129 027 (AS BELORELIABILITY) 15. Dezember 1984 *

Cited By (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1993025718A1 (en) * 1992-06-09 1993-12-23 Matec Holding Ag Process for making mouldings and use thereof
FR2742856A1 (en) * 1995-12-21 1997-06-27 Renault Automobile heat exchanger with permeable three-dimensional linked lattice structure
EP0804982A2 (en) * 1996-04-19 1997-11-05 Leichtmetallguss-Kokillenbau-Werk Illichmann GmbH Process for preparing metal foam parts
EP0804982A3 (en) * 1996-04-19 1997-11-12 Leichtmetallguss-Kokillenbau-Werk Illichmann GmbH Process for preparing metal foam parts
US5865237A (en) * 1996-04-19 1999-02-02 Leichtmetallguss-Kokillenbau-Werk Illichmann Gmbh Method of producing molded bodies of a metal foam
DE19717894B4 (en) * 1996-05-02 2005-06-23 Mepura Metallpulvergesellschaft M.B.H. Process for the production of porous matrix materials, in particular moldings based on metals, and semi-finished products therefor
EP0868956A1 (en) * 1997-02-28 1998-10-07 Machner &amp; Saurer GmbH Process for preparing metal articles with internal porosity
AT406557B (en) * 1997-02-28 2000-06-26 Machner & Saurer Gmbh METHOD FOR PRODUCING METAL BODIES WITH INNER POROSITY
EP0927591A2 (en) * 1998-01-02 1999-07-07 Wilhelm Karmann GmbH Process for forming a workpiece with a metal foam layer
EP0927591A3 (en) * 1998-01-02 2002-07-03 Wilhelm Karmann GmbH Process for forming a workpiece with a metal foam layer
WO1999052661A1 (en) * 1998-04-09 1999-10-21 Mepura Metallpulvergesellschaft Mbh Ranshofen Method for producing forms and foamed metal forms
EP1352696A3 (en) * 1998-04-09 2005-04-27 Alulight International GmbH Method for producing foamed metal composites
WO1999064287A1 (en) * 1998-06-09 1999-12-16 M.I.M. Hüttenwerke Duisburg Gmbh Method for reinforcing a cavity of a motor vehicle structural member
EP1008406A3 (en) * 1998-12-09 2000-09-06 Bayerische Motoren Werke Aktiengesellschaft Method for the production of a hollow article filled with a light-metal foam structure
EP1008406A2 (en) * 1998-12-09 2000-06-14 Bayerische Motoren Werke Aktiengesellschaft Method for the production of a hollow article filled with a light-metal foam structure
DE19908867A1 (en) * 1999-03-01 2000-09-07 Arved Huebler Composite body useful in machine construction comprises metal foam and solid parts joined together by a metallurgical bond of fused adjoining material layers
WO2002042707A1 (en) * 2000-11-27 2002-05-30 Stork Prints B.V. Heat exchanger
NL1016713C2 (en) * 2000-11-27 2002-05-29 Stork Screens Bv Heat exchanger and such a heat exchanger comprising thermo-acoustic conversion device.
US7131288B2 (en) 2000-11-27 2006-11-07 Inco Limited Heat exchanger
WO2007101799A2 (en) * 2006-03-03 2007-09-13 Deutsches Zentrum für Luft- und Raumfahrt e.V. Composite metal-aerogel material
WO2007101799A3 (en) * 2006-03-03 2008-03-13 Deutsch Zentr Luft & Raumfahrt Composite metal-aerogel material
WO2007128374A1 (en) * 2006-05-04 2007-11-15 Alulight International Gmbh Method for production of composite bodies and composite bodies produced thereby
EP2295390A1 (en) 2009-09-04 2011-03-16 Manfred Jaeckel Method for producing a cellular sinter mould
DE102009040258A1 (en) 2009-09-04 2011-03-24 Jaeckel, Manfred, Dipl.-Ing. Process for producing a cellular sintered body
EP2679564A1 (en) 2009-09-04 2014-01-01 Manfred Jaeckel Method for producing a cellular sinter mould
WO2011151193A1 (en) * 2010-05-31 2011-12-08 Siemens Aktiengesellschaft Method for generating a closed-pore metal foam and component which has a closed-pore metal foam
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WO2018130550A1 (en) * 2017-01-12 2018-07-19 Lisa Dräxlmaier GmbH Vehicle component with foamed electrical conductive structure and manufacturing method for such a component

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CA2044120A1 (en) 1991-12-09
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CA2044120C (en) 2001-05-01
DE4101630A1 (en) 1991-12-12
US5151246A (en) 1992-09-29
DE59108133D1 (en) 1996-10-10
JP2898437B2 (en) 1999-06-02
EP0460392B1 (en) 1996-09-04

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