Oxidation and wear resistant brazed coating
A method includes applying a material coating to a surface of a machine component, wherein the material coating is formed from a combination of a hardfacing material, aluminum-containing particles, and a braze material. The method also includes thermally treating the material coating at a temperature to generate an oxide layer comprising aluminum from the aluminum-containing particles, wherein the oxide layer is configured to reduce oxidation of the hardfacing material, and the braze material is configured to facilitate binding between the material coating and the surface of the machine component.
1. A method, comprising:
applying a material coating to a surface of a machine component, wherein the material coating is formed from a combination of a hardfacing material, aluminum-containing particles, and a braze material;
pre-heating the material coating to precipitate a plurality of intermetallic phases based on the aluminum-containing particles, the hardfacing material, and the braze material; and
after pre-heating the material coating, thermally treating the material coating at an oxidizing temperature to oxidize aluminum in the aluminum-containing particles to generate an oxide layer comprising the aluminum in the aluminum-containing particles, wherein the oxide layer is configured to reduce oxidation of the hardfacing material, and the braze material is configured to facilitate binding between the material coating and the surface of the machine component, and wherein the aluminum-containing particles consist essentially of aluminum metal, an aluminum alloy, an aluminum intermetallic species, or a combination thereof.
2. The method of claim 1 , comprising forming a pre-sintered preform (PSP) using a mixture of particles comprising the hardfacing material, the aluminum containing particles, and the braze material; and
thermally treating the PSP at an additional temperature, prior to thermally treating the material coating at the oxidizing temperature, to form the material coating and couple the material coating to the surface of the machine component, wherein the additional temperature is higher than the oxidizing temperature.
3. The method of claim 2 , wherein the additional temperature is between 1000° C. and 1300° C.
4. The method of claim 1 , wherein the hardfacing material comprises particles having a first size distribution, the aluminum-containing particles have a second size distribution, and the first size distribution is different than the second size distribution.
5. The method of claim 1 , wherein the braze material comprises nickel.
6. The method of claim 1 , wherein the hardfacing material comprises M-Mo—Cr—Si, where M comprises Ni or Co.
7. The method of claim 1 , wherein the braze material is configured to wet boron, silicon, or a combination thereof.
8. The method of claim 1 , wherein approximately 20% of the composition of the material coating is the braze material.
9. The method of claim 1 , wherein the aluminum-containing particles consist essentially of aluminum metal.