Metal matrix composite material and method of manufacturing same

Patent metadata

Field	Value
Publication number	US-2020157009-A1
Application number	US-201916669616-A
Country	US
Kind code	A1
Filing date	Oct 31, 2019
Priority date	Nov 16, 2018
Publication date	May 21, 2020
Grant date	—

Abstract

A composite material having a grainy appearance, this composite material including a metal matrix which represents, in terms of volume fraction, between 50 and 95% of the grainy composite material, the ceramic particles having a diameter that lies in the range 0.1 to 2 mm and which represent, in terms of volume fraction, between 50 and 5% of the composite material are dispersed in the metal matrix and form the remainder of this grainy composite material. A method for manufacturing a grainy synthetic material.

First claim

1 . A sintered composite material having a grainy appearance, said composite material comprising a metal matrix which represents, in terms of volume fraction, between 50 and 95% of the grainy composite material, wherein ceramic particles having a diameter that lies in the range 0.1 to 2 mm are dispersed in the metal matrix and form the remainder of this grainy composite material.

2 . The material according to claim 1 , wherein the metal matrix is obtained from a metal powder formed by a plurality of particles having a D90 value of a cumulative function of less than 100 μm.

3 . The material according to claim 1 , wherein the metal matrix is chosen from the group consisting of austenitic stainless steels, titanium alloys, gold, silver, platinum and palladium alloys, copper alloys and aluminium alloys.

4 . The material according to claim 2 , wherein the diameter of the ceramic particles lies in the range 0.2 to 2 mm.

5 . The material according to claim 2 , wherein the diameter of the ceramic particles lies in the range 0.25 to 0.75 mm.

6 . The material according to claim 2 , wherein the ceramic particles represent, in terms of volume fraction, between 30 and 5% of the composite material, and the diameter thereof lies in the range 0.25 to 0.75 mm.

7 . The material according to claim 2 , wherein the ceramic particles represent, in terms of volume fraction, between 20 and 10% of the composite material, and the diameter thereof lies in the range 0.25 to 0.75 mm.

8 . The material according to claim 2 , wherein the ceramic particles are chosen from the group consisting of aluminium oxides, silicon oxides, zirconium oxides, titanium oxides, diamond, silicon carbides, silicon nitrides, titanium carbides, titanium borides and zirconium borides.

9 . The material according to claim 8 , wherein the ceramic particles are chosen from the group consisting of corundums and silicates.

10 . The material according to claim 9 , wherein it is obtained from a mixture of grade 2 titanium and corundum.

11 . The material according to claim 10 , wherein it is obtained from a mixture of a grade 2 titanium powder formed by particles with a D90 value of a cumulative function of less than 25 μm and of corundum according to the following volume fractions:
15 vol % corundum having a particle size that lies in the range 297 μm to 420 μm;
25 vol % corundum having a particle size that lies in the range 297 μm to 420 μm;
15 vol % corundum having a particle size that lies in the range 420 μm to 595 μm;
25 vol % corundum having a particle size that lies in the range 420 μm to 595 μm.

12 . The material according to claim 11 , wherein it is obtained from a mixture of a stainless steel 1.4435 powder formed by particles with a D90 value of a cumulative function of less than 22 μm and of corundum according to the following volume fractions:
15 vol % corundum having a particle size that lies in the range 297 μm to 420 μm;
25 vol % corundum having a particle size that lies in the range 297 μm to 420 μm;
15 vol % corundum having a particle size that lies in the range 420 μm to 595 μm;
25 vol % corundum having a particle size that lies in the range 420 μm to 595 μm.

13 . The material according to claim 2 , wherein the ceramic particles are chosen from the group consisting of luminescent inorganic ceramic particles.

14 . The material according to claim 13 , wherein the luminescent inorganic particles are based on rare earth aluminates, rare earth silicates or europium- and/or dysprosium-doped strontium aluminates.

15 . The material according to claim 14 , wherein it is obtained from a mixture of a stainless steel 1.4435 powder and luminescent inorganic particles.

16 . The material according to claim 15 , wherein the composite material is formed by a stainless steel 1.4435 powder of particles with a D90 value of a cumulative function of less than 22 μm, and by a 15% volume fraction of europium- and/or dysprosium-doped strontium aluminate particles, the particle size whereof lies in the range 400 to 600 μm.

17 . A method for manufacturing a composite material having a visually grainy appearance comprising the steps of:
obtaining a powder formed by a plurality of metal particles having a D90 value of a cumulative function of less than 100 μm; obtaining ceramic particles, the diameter whereof lies in the range 0.1 to 2 mm; mixing the metal powder particles with the ceramic particles to obtain a so-called feedstock, the metal powder representing, in terms of volume fraction, between 50% and 95% of the mixture obtained; producing a so-called green body by pressing or by injecting the metal powder particles-ceramic particles mixture into a mould; subjecting the green body to sintering treatment at a temperature in the range 600 to 1,400° C. and for a duration in the range 1 h to 4 h to obtain a grey body made of composite material having a visually grainy appearance and comprising a metal matrix which represents, in terms of volume fraction, between 50% and 95% of this part, and wherein the ceramic particles are dispersed and form the remainder of this part.

18 . The method according to claim 17 , wherein, when the metal powder particles are mixed with the ceramic particles to obtain the so-called feedstock, an organic binder is added to the mixture, which binder represents 2 to 40% of the feedstock, in terms of volume fraction, the mixture of metal powder particles, ceramic particles and organic binder then being pressed or injected into the mould, then the organic binder being removed from the green body during at least one debinding step.

19 . The method according to claim 17 , wherein the grey body is machined to reduce the surface roughness.

20 . The method according to claim 19 , wherein the grey body is ground.

21 . The method according to claim 19 , wherein the grey body is polished.

22 . The method according to claim 19 , wherein the grey body is sanded.

23 . The method according to claim 19 , wherein the grey body is subjected to chemical or electrochemical etching in order to reveal the different phases composing the composite material, and to enhance the contrast between these phases.

24 . The method according to claim 19 , wherein the grey body is subjected to an electrodeposition treatment or to an anodising treatment.

Assignees

• Swatch Group Res & Dev Ltd

Inventors

• Porret Joel
• Winkler Yves

Classifications

• B22F2999/00

  Aspects linked to processes or compositions used in powder metallurgy · CPC title

• C22C33/0292

  with more than 5% preformed carbides, nitrides or borides · CPC title

• C04B35/584

  based on silicon nitride · CPC title

• C04B35/5611

  based on titanium carbides · CPC title

• A44C27/001

  Materials for manufacturing jewellery · CPC title