DE102015118787A1 - Method and device for producing metal foam composite bodies and metal foam composite bodies - Google Patents

Abstract

The invention relates to a method for producing metal foam composite bodies, in particular sandwich panels, with cover layers of aluminum or steel and a metal foam body made of light metal or a light metal alloy between the cover layers, wherein pressed semi-finished products of light metal or a light metal alloy and a blowing agent in a prefabricated container is inserted and after filling the container by a forming process with thickness reduction to a composite blank, consisting at least of container walls and a core of pressed aluminum foam semi-finished product is compacted and the blank then in an oven process to form a closed-cell foam body made of light metal or a light metal Alloy is heated to form a metal foam composite. The invention further relates to a blank for producing a metal foam composite body, a metal foam composite body of this and a use of such a metal foam composite body.

Description

The invention relates to a method and an apparatus for producing metal foam composite bodies. The invention further relates to a metal foam composite, in particular a composite plate.

Metal foam composites are very popular as sandwich panels because of their high structural strength combined with low specific gravity, the cover sheets being made from aluminum panels with an aluminum based aluminum foam core (AFS) or with steel facing sheets with aluminum-based (SAS) metal foam core. Mainly metal foam composite panels are distinguished as AFS (aluminum-aluminum foam-aluminum sandwiches) and SAS (steel-aluminum foam-steel sandwiches with metallic bond).

Areas of application are primarily in the construction industry, rail vehicle construction, aerospace, architecture, industrial construction, shipbuilding and other economic sectors.

Such composite elements are produced as metallurgically integral bodies and metal lightweight products without additives, such as adhesives, rivets or screws, so that these metal foam composite bodies also have a high aesthetic appeal.

However, these building boards are relatively expensive, since they are made in individual production and without a plant regime that allows a multi-layered utilization.

Conventionally, to produce the aluminum foam body elements which later, after the thermal frothing, form the aluminum foam body between the cover layers of the sandwich panel, an aluminum metal powder with a blowing agent, e.g. TiH2 mixed and then compacted by means of a plunger in an axial compression molding step. In axial pressing, a cylindrical block of the powder metallurgy foam material is pressed through a die to form a foamable molding material. Subsequently, the molding material (semifinished product, Al foam body elements) is placed for foaming in a mold or in the auszuschäumende component and foamed after heating the foam mold or the component with the foam material (Al-foam body elements) the component. After the desired formation of the metal foam, the component is cooled.

A method for producing a metal foam composite body using a roll-compacted container as a blank is known from EP 1 423 222 B1 However, although a relatively complicated process for forming the blank by filling a pre-mixed metal / propellant powder into a container precompression of the powder and evacuation of the container after its gas-tight sealing are required.

However, this manufacturing method for a composite blank on the one hand a foamable core material of metal or metal alloy and blowing agent and on the other hand has the cover layers formed from the upper and lower walls of the container, however, is relatively expensive.

The invention is therefore based on the object to provide a method and apparatus for producing metal foam composite bodies, which can be compared to the prior art by a significant simplification in terms of process management and thus execute in terms of manufacturing costs.

The invention is also based on the object to provide a correspondingly producible metal foam composite body.

The aforementioned objects are achieved by the features of claims 1, 11, 12 and 13.

The invention is characterized in that in a prepared metal container whose upper and lower walls form the later outer layers of the finished metal foam composite body, the foamable material, ie the material of metal or a metal alloy and a blowing agent, in particular aluminum or an aluminum alloy and blowing agent (TiH ₂ ) are already inserted as pressed pressed semi-finished products. Subsequently, the container thus filled is sealed on all sides and highly compressed in a forming, preferably rolling, with substantial reduction in thickness and in this way without vacuum or gas guiding processes or the processing of metal or Treibmittelpulvermischungen a blank made of composite material, consisting of the foamable pressed semi-finished material and the cover layers in a high density composite. This blank is subjected to a subsequent furnace process for foaming the interior space formed between the cover layers and filled with the pressed semifinished product of foamable material to form a sandwich metal foam composite body, preferably with a closed-cell foam body.

Such sandwich foam sheets are much easier and high damping capacity as lightweight panels of z. As aluminum solid material, especially if the outer layers are made of aluminum.

Preferably, the pressed semi-finished products are inserted as rods, rods or as plate-shaped elements in intersecting layers or as a small body or granules in the interior of the container, so that the interior of the container is filled almost completely, before the container z. B. is completely closed by welding or otherwise, and is subjected to a forming process, in particular rolling process for the production of the compacted blank.

Possibly. is the blank before further processing to a metal foam composite body, such as a sandwich panel with outer layers (depending on the container) z. As aluminum or steel cut to ensure appropriate finished dimensions before or after foaming of the metal foam body element.

Preferably, the Fertigmaßbearbeitung in terms of z. B. a plate size of the sandwich panels before the furnace process under a release treatment of the blank.

The invention will be explained in more detail below with reference to an embodiment and associated drawings. In this show:

1 a basic procedure of a method for producing a metal foam composite body, in particular a sandwich panel;

2 a skeletal representation of a container;

3 an end view of the container after 1 ;

4 a sectional view of the filled with the pressed semi-finished material of a foamable light metal material container;

5 a sectional view of a blank for the production of a metal foam composite body in a sectional view after a forming, in particular rolling process;

6 a detail of the layer arrangement of the pressed semifinished material in the container after 4 ;

7 a detail of the vents in one end of the container after 3 ;

8a an external view of the filled, filled with the pressed semi-finished material from pressed semi-finished foam-forming light metal material Behjälters before forming (especially rolling), and

8b a spatial representation of a compacted blank with separate end walls of the container, prepared for transfer into a process furnace for performing foaming process for forming a metal foam composite body (sandwich).

The embodiment of the method according to the invention is schematically based on the procedure of 1 explained.

The cover layer material required in each case for the production of the respective foamed metal foam composite, in particular a metal foam composite panel as sandwich (AFS or SAS (aluminum foam core composite panel, steel-aluminum core composite panel)) determines the production of a parallelepiped-shaped, in particular plate-shaped, container Blank for the production of the sandwich plate as provided here embodiment of the metal foam composite body forms. The cover layer materials 1 . 2 of the container 100 Thus, the future cover layer plates of the prefabricated part form and these usually consist of aluminum or an aluminum alloy or of steel, these on forehead and side plates 3 . 4 connected to a container, preferably welded.

First, the container 100 (please refer 1 ) is formed as an open container and it is in these the foamable material for forming the foam core as a pressed semi-finished product 6 aluminum-based, generally an aluminum-magnesium-silicon alloy, in which the blowing agent (generally TiH _{2 is included} integrated, inserted.

The pressed semi-finished products 6 are preferably formed in the form of rods or rods with preferably rectangular cross-section (see. 4 ), the crosswise, ie intersecting layers in the opening of the container 100 be stacked. Then it becomes a container 100 through the upper cover plate 1 , That is, the upper container wall closed, this state as a graphical representation in 4 is shown. Preferably, the container 100 tightly welded. To the inside of the container 100 and the structure of pressed semifinished rods 6 of preferably rectangular cross section air contained (see. 6 ) in conjunction with the subsequent high-grade compaction of the container 100 By a subsequent forming process to allow the outflow, are vent holes 5 in a preferably in both end walls 3 or on the long sides of the container 100 intended.

After closing the container 100 So this is subjected to a high-grade forming and compression process in particular a rolling process, which leads to a drastic compression of the entire container 100 including the foamable semi-finished material contained in it 6 and drastic reduction in thickness, at the same time an intermetallic compound between the upper and lower layers of the foamable semifinished material 6 and upper cover sheet material 1 or the lower cover layer material 2 entry.

In this way, the container is removed 100 with the foamable material stack of pressed, foamable semifinished material contained therein 6 preferably consisting of AlMg3 (... 4) Si6 TiH ₂ 1% or AlMg1Si0.6 TiH ₂ 0.8% a blank made of composite material, which is then optionally cut or brought to the desired finished size of the later metal foam core sandwich and is prepared so foamed in a furnace process, not shown here, for the production of the finished metal foam composite body.

Preferably, the container is in a degree of z. B. 300 × 160 cm with a height (thickness) of 10 cm formed whereas the later to be removed side plates z. B. only have a thickness of 2.4 cm. Such a design leads to a final product as a sandwich plate with a thickness of about 20 mm, wherein an inner foam core has a thickness of about 60 mm, with cover layers (upper and lower outer layer material plates 1 respectively. 2 ) with a thickness of about 2 mm).

Of course, also different materials for the outer layers 1 . 2 and the front and longitudinal plates 3 . 4 of the container 100 to get voted.

In this way, a substantial increase in the efficiency of the manufacturing process for the metal foam composite body in the form of the preparation of the corresponding blank is possible.

1 shows the container structure 100 in skeleton representation with the sectional view AA shown in FIG 5 However, this is the state of the finished compacted blank after the rolling process with the outer layers 1 and 2 and the compacted pressed semi-finished material 6 represents.

3 is a look at the front 3 of the container 100 with the ventilation openings provided there 5 which detects the escape of the air from the container assembly in connection with the preferably realized by rolling compression process for the production of the blank, which in 5 is shown, are provided.

4 shows a detail in the arrangement of the vents 5 at the front 3 of the container 100 while 6 the inherent air pockets within the stack assembly ejected semi-finished products 6 after layering in the container 100 (please refer 4 illustrated). 6 is a detail 4 , In these are the pressed semi-finished products of foamable material on aluminum-magnesium-silicon base combined with the blowing agent in layers and crosswise, ie, layer by layer crossing substantially 90 ° in the container 100 sandwiched. 4 So it shows the one with welds 6 sealed container before the compression process to form the blank, which is preferably prepared by rolling and leads to a drastic reduction in thickness. Preferably, depending on the design of the later sandwich panel, the opposite end sides of the blank are separated, so that, as in 8b shown the finished blank in preparation for the subsequent furnace process exposes the pressed semi-finished rods to a highly pre-compacted body, as this 8b clarified.

In 8a is the filled container 100 before the forming process (rolling) shown.

The invention provides a much more efficient method of preparing a composite blank to form a metal foam composite in a subsequent furnace process.

Such foamed sandwich panels are used in particular as container walls for dangerous goods or are used in vehicle and shipbuilding or in aerospace engineering. They combine relatively low weight with extraordinary strength and insulating effect against thermal or acoustic or from pressure waves resulting loads.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 1423222 B1 [0007]

Claims (13)

Process for producing metal foam composite bodies, in particular sandwich panels, with cover layers ( 1 . 2 ) of aluminum or steel and a metal foam body of light metal or a light metal alloy between the cover layers ( 1 . 2 ), whereby pressed semi-finished products ( 6 ) of light metal or a light metal alloy and a propellant in a prefabricated container ( 100 ) and after filling the container ( 100 ) this by a reduction process under thickness reduction to a blank ( 8th ) of composite material, consisting at least of container walls and a core of pressed aluminum foam semi-finished product ( 6 ) and the blank ( 8th ) is subsequently heated in a furnace process for forming a closed-cell foam body made of light metal or a light metal alloy to form a metal foam composite body. Method according to claim 1, characterized in that the pressed semifinished product ( 6 ) (From AlMg3 (up to 4) Si ₆ +/- 1) TiH ₂₁ or AlMg1Si 0.6 _TiH2 0.8 exists. Method according to claim 1 or 2, characterized in that the container ( 100 ) from cover sheets ( 1 . 2 ) with a material thickness which is a multiple of the material thickness of front or side plates of the container ( 100 ) having. Method according to one of the preceding claims 1 to 3, characterized in that the container ( 100 ) after multiple insertion of the pressed semi-finished material ( 6 ) made of aluminum or an aluminum alloy and propellant closed on all sides, in particular welded. Method according to one of the preceding claims 1 to 4, characterized in that the pressed semi-finished material ( 6 aluminum or aluminum alloy and propellants in the form of rods or rods into the container ( 100 ) is inserted in several layers. A method according to claim 5, characterized in that the layers of pressed semi-finished material ( 6 ) within the container ( 100 ) are arranged crosswise to each other and lie on top of each other. Method according to at least one of the preceding claims 1 to 6, characterized in that an interior of the container ( 100 ) by the pressed semi-finished material ( 6 ) made of aluminum or an aluminum alloy and blowing agent is substantially completely filled. Method according to one of the preceding claims 1 to 7, characterized in that the container ( 100 ) at its end faces ( 3 ) Vents ( 5 ), preferably having a diameter of about 5 mm. Method according to one of the preceding claims 1 to 8 for forming a metal foam composite sheet having a Schaumkerndicke of about 16 mm and a top layer thickness of about 2 mm, an interior of the container has a thickness of about 200 mm and the cover plates of the container ( 100 ) Have a thickness of about 100 mm on both sides of the inner space and having a thickness of about 400 mm before rolling the container filled with the pressed semi-finished material. Method according to one of the preceding claims 1 to 9, characterized in that after the forming, in particular rolling of the composite blank of pressed semi-finished product ( 6 ) and cover layers ( 8th ) before or after a furnace process for foaming ( 1 . 2 ) of the foam core material is divided. Blank for producing a metal foam composite body formed from a compacted, in particular rolled container ( 100 ) in the multi-layer pressed semi-finished material ( 6 ) made of light metal, in particular aluminum or aluminum alloy and blowing agent is inserted, compacted by forming, in particular rolling. Metal foam composite body of cover layers and a foam core of light metal, in particular aluminum or aluminum alloy formed from a container ( 100 ) with in this inserted pressed semi-finished products ( 6 ) made of light metal, in particular aluminum or an aluminum alloy with propellant to form a closed-cell foam core in a furnace process. Use of the metal foam composite according to claim 12 as a lightweight structural element, in particular in shipbuilding, aerospace technology or vehicle technology for energy absorption or as wall material of transport containers (in particular for dangerous goods).

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