Hardface coating systems and methods for metal alloys and other materials for wear and corrosion resistant applications
The present disclosure relates generally to hardface coating systems and methods for metal alloys and other materials for wear and corrosion resistant applications. More specifically, the present disclosure relates to hardface coatings that include a network of titanium monoboride (TiB) needles or whiskers in a matrix, which are formed from titanium (Ti) and titanium diboride (TiB 2 ) precursors by reactions enabled by the inherent energy provided by the process heat associated with coating deposition and, optionally, coating post-heat treatment. These hardface coatings are pyrophoric, thereby generating further reaction energy internally, and may be applied in a functionally graded manner. The hardface coatings may be deposited in the presence of a number of fluxing agents, beta stabilizers, densification aids, diffusional aids, and multimode particle size distributions to further enhance their performance characteristics.
1. A method for surface treating a metal alloy substrate or other material substrate to provide improved wear and corrosion resistance for a resulting composite structure, comprising:
depositing a layer of titanium and boron on a surface of the substrate in the presence of sufficient deposition process heat such that diffusion interactions occur and the titanium and boron react to form elongate titanium monoboride structures in a matrix, wherein the titanium and boron partially diffuse into the surface of the substrate to form a reinforced material intermingled with the surface of the substrate to provide the composite structure;
wherein one or more of the titanium and boron are deposited at a temperature of about 800 degrees C. or more.
2. The surface treatment method of claim 1 , wherein the boron is deposited as titanium diboride.
3. The surface treatment method of claim 1 , wherein the matrix comprises titanium.
4. The surface treatment method of claim 1 , wherein the matrix comprises β-titanium.
5. The surface treatment method of claim 1 , wherein the titanium and boron are deposited via one of a thermal spraying and physical vapor deposition technique.
6. The surface treatment method of claim 1 , wherein one or more of the titanium and boron are deposited in a substantially melted state.
7. The surface treatment method of claim 1 , wherein the layer of titanium and boron further comprises a fluxing agent selected from the group consisting of CaF 2 , Si, and B.
8. The surface treatment method of claim 1 , wherein the layer of titanium and boron further comprises a beta stabilizer selected from the group consisting of molybdenum, vanadium, tantalum, niobium, manganese, iron, chromium, cobalt, nickel, copper, and silicon.
9. The surface treatment method of claim 1 , wherein the layer of titanium and boron further comprises a densification aid selected from the group consisting of Fe, Mo, and an Fe alloy.
10. The surface treatment method of claim 1 , wherein the layer of titanium and boron further comprises a diffusional aid selected from the group consisting of CaCO 3 , CaF 2 , NaHCO 3 , and KBF 4 .
11. The surface treatment method of claim 1 , wherein the layer of titanium and boron comprises a plurality of particle sizes to aid diffusion interactions.
12. The surface treatment method of claim 1 , wherein the layer of titanium and boron is deposited on the substrate in a functionally gradient manner via one of a thermal spraying and physical vapor deposition technique.
13. The surface treatment method of claim 1 , wherein the layer of titanium and boron is subjected to heat treatment subsequent to deposition on the substrate.
14. A method for surface treating a metal alloy substrate or other material substrate to provide improved wear and corrosion resistance for a resulting composite structure, comprising:
depositing a layer of titanium and boron on a surface of the substrate in the presence of sufficient deposition process heat such that diffusion interactions occur and the titanium and boron react to form elongate titanium monoboride structures in a matrix, wherein the titanium and boron partially diffuse into the surface of the substrate to form a reinforced material intermingled with the surface of the substrate to provide the composite structure;
wherein one or more of the titanium and boron are deposited at a temperature of about 800 degrees C. or more; and
subsequently heat treating the layer of titanium and boron.