US 12,076,790 B2
Metal foam bodies and process for production thereof
René Poss, Karlsruhe (DE); Monika Berweiler, Maintal (DE); and Meike Roos, Büdingen (DE)
Assigned to Evonik Operations GmbH, Essen (DE)
Appl. No. 17/053,340
Filed by EVONIK OPERATIONS GMBH, Essen (DE)
PCT Filed Sep. 25, 2020, PCT No. PCT/EP2020/076826
§ 371(c)(1), (2) Date Nov. 5, 2020,
PCT Pub. No. WO2021/058706, PCT Pub. Date Apr. 1, 2021.
Claims priority of application No. 19199643 (EP), filed on Sep. 25, 2019.
Prior Publication US 2021/0276091 A1, Sep. 9, 2021
Int. Cl. B22F 3/11 (2006.01); B22F 1/05 (2022.01); B22F 3/24 (2006.01)
CPC B22F 3/1137 (2013.01) [B22F 1/05 (2022.01); B22F 3/1146 (2013.01); B22F 2003/242 (2013.01); B22F 2003/248 (2013.01); B22F 2301/052 (2013.01); B22F 2303/30 (2013.01)] 18 Claims
 
1. A process for producing a metal foam body, comprising the following steps:
(a) providing a metal foam body A, comprising two metallic components in the form of an alloy, wherein the alloy consists of either nickel and cobalt or nickel and copper;
(b) applying a metal-containing powder MP to metal foam body A to obtain metal foam body AX, wherein the metal-containing powder MP is selected from the group consisting of: a mixture consisting of aluminium powder and chromium powder; a mixture consisting of aluminium powder and molybdenum powder; a pulverulent alloy consisting of aluminium and chromium; and a pulverulent alloy consisting of aluminium and molybdenum;
(c) treating the metal foam body AX thermally to achieve alloy formation between the metallic components of metal foam body A and the metal-containing powder MP to thereby obtain metal foam body B, wherein:
the highest temperature of the thermal treatment of metal foam body AX is in the range from 680 to 715° C.; and
the total duration of the thermal treatment in the temperature range from 680 to 715° C. is between 5 and 240 seconds;
wherein: after step c), alloy formation is found in the upper regions of the metal foam, but unalloyed regions remain within central areas of the metal foam;
the metal-containing powder MP is applied to the metal foam body A using a polyethyleneimine binder with a molecular weight in the range of 700 000 to 800 000 g/mol;
the binder is completely converted to gas at a temperature of 100-400° C.; and
MP and binder are applied to A in one step as a suspension of MP in binder.