Composite wires for coating substrates and methods of use
View Patent ↗A composite wire for producing a wear resistant and corrosion resistant coating on a substrate by thermal spraying, spray and fuse, or welding techniques are disclosed. The physical properties of the coating are particularly suited for high-temperature erosion-corrosion environments. The resultant coating exhibits good hardness, toughness, and bonding characteristics. The composite wire comprises a metallic outer sheath and an inner core containing boron carbide and chrome carbide.
1. A method of forming a wear resistant and corrosion resistant coating on a substrate comprising the steps of:
providing a wire having a metallic outer sheath and a powdered inner core, wherein the inner core comprises at least about 35% by weight of boron carbide and chrome carbide in an amount between about 67% and about 185% by weight of the amount of boron carbide;
melting the wire using an electric arc heat source to form a melt;
atomizing and spraying the melt onto a substrate by compressed gas;
wherein the composite wire is selected to form a coating on the substrate comprising the metal of the sheath, chrome carbide, and boron, and
permitting the coating to solidify.
2. The method of claim 1 wherein the arc melts the wire, and the melt comprises the metal of the sheath, chrome, boron and carbon.
3. The method of claim 1 , wherein the outer sheath is formed of an essentially pure metal.
4. The method of claim 1 , wherein the outer sheath is formed of an alloy comprising a base metal.
5. The method of claim 4 , wherein the base metal of the alloy is selected from the group consisting of iron, nickel, aluminum, molybdenum, tantalum, copper, and titanium.
6. The method of claim 4 , wherein the alloy is a nickel base alloy.
7. The method of claim 6 , wherein the nickel base alloy further comprises chromium.
8. The method of claim 7 , wherein the nickel base alloy further comprises at least about 40% by weight of nickel.
9. The method of claim 8 , wherein the nickel base alloy further comprises molybdenum.
10. The method of claim 9 , wherein the nickel base alloy is an alloy 625.
11. The method of claim 1 , wherein the inner core further comprises another carbide in addition to boron carbide and chrome carbide.
12. The method of claim 1 , wherein the inner core further comprises at least one carbide selected from the group consisting of tungsten carbide, vanadium carbide and titanium carbide.
13. The method of claim 1 , wherein the inner core further comprises a metal powder.
14. The method of claim 1 , wherein the inner core further comprises a composite powder.
15. The method of claim 1 , wherein the inner core further comprises a boride.
16. The method of claim 1 , wherein the inner core further comprises an oxide.