Wear resistant thermal spray alloy

Abstract

A thermal spray alloy system that is more resistant to corrosion and erosion and hard-wear abrasion than conventional alloy compositions, and may be applied to a substrate by conventional welding techniques or thermal spray. The alloy may comprise carbon, nitrogen, and boron, in addition to chromium and other elements. The object to be coated may be any downhole component used in the oil and gas industry, or may be applied to any object or tool that needs an increased wear and/or corrosive protection layer including in diverse fields such as marine, chemical processing, and refining. A thermal spray coating with the alloy composition provides increased strength and resistance to spalling, breaking, cracking, deforming, and crack formation.

What is claimed is: 
     
         1 . An iron-based alloy, the composition comprising the following components:
 about 0.2 wt % to about 2.0 wt % of carbon;   about 0.2 wt % to about 2.0 wt % of nitrogen;   about 0.4 wt % to about 7.0 wt % of boron;   about 0.0 wt % to about 5.0 wt % of manganese;   about 0.0 wt % to about 7.0 wt % of chromium;   about 0.0 wt % to about 5.0 wt % of titanium;   about 0.0 wt % to about 2.5 wt % of aluminum; and   about 0.0 wt % to about 2.0 wt % of zirconium,   with iron being a principal remaining element of the composition.   
     
     
         2 . The composition of  claim 1 , wherein the composition comprises about 0.3 wt % to 1.5 wt % of carbon and 0.3 wt % to 1.5% nitrogen. 
     
     
         3 . The composition of  claim 1 , wherein the composition comprises about 0.3 wt % to 1.15 wt % of carbon and 0.3 wt % to 1.15% nitrogen. 
     
     
         4 . The composition of  claim 1 , wherein the composition comprises about 1.0 wt % carbon and about 1.0 wt % nitrogen. 
     
     
         5 . The composition of  claim 1 , wherein the composition of carbon and nitrogen is approximately the same. 
     
     
         6 . The composition of  claim 1 , wherein the composition comprises about 1.5 wt % to about 6.0 wt % of boron. 
     
     
         7 . The composition of  claim 1 , wherein the composition comprises at least 2.0 wt % of boron. 
     
     
         8 . The composition of  claim 1 , wherein the composition comprises at least 5.0 wt % of boron. 
     
     
         9 . The composition of  claim 1 , wherein the composition comprises about 0.5 wt % to about 2.0 wt % of manganese. 
     
     
         10 . The composition of  claim 1 , wherein the composition comprises about 0.5 wt % to about 2.0 wt % of chromium. 
     
     
         11 . The composition of  claim 1 , wherein the composition comprises about 0.3 wt % to about 3.0 wt % of titanium. 
     
     
         12 . The composition of  claim 1 , wherein the composition comprises about 0.3 wt % to about 1.0 wt % of aluminum. 
     
     
         13 . The composition of  claim 1 , wherein the composition comprises about 0.3 wt % to about 1.0 wt % of zirconium. 
     
     
         14 . The composition of  claim 1 , wherein the composition is contained within a cored wire. 
     
     
         15 . The composition of  claim 1 , wherein the amount of boron is configured to provide hardness to the alloy. 
     
     
         16 . The composition of  claim 1 , wherein the amount of carbon and nitrogen is configured to keep carbon in solution to the alloy. 
     
     
         17 . The composition of  claim 1 , wherein the composition is effective to prevent micro-cracks from forming in the alloy. 
     
     
         18 . The composition of  claim 1 , wherein the composition is configured for being thermally sprayed on a substrate. 
     
     
         19 . The composition of  claim 1 , wherein the composition is configured for being welded on a substrate. 
     
     
         20 . A stainless steel alloy, the composition comprising the following components:
 about 0.2 wt % to about 1.5 wt % of carbon;   about 0.2 wt % to about 1.5 wt % of nitrogen;   about 10.0 wt % to about 35.0 wt % of chromium;   about 0.0 wt % to about 35.0 wt % of nickel;   about 0.0 wt % to about 3.0 wt % of silicon;   about 0.0 wt % to about 7.5 wt % of molybdenum;   about 0.0 wt % to about 8.0 wt % of copper; and   about 0.1 wt % to about 2.0 wt % of boron,   with iron being a principal remaining element of the composition.   
     
     
         21 . The composition of  claim 20 , wherein the composition comprises about 0.4 wt % to 1.15 wt % of carbon and 0.3 wt % to 1.15% nitrogen. 
     
     
         22 . The composition of  claim 20 , wherein the composition comprises about 2.0 wt % to about 25.0 wt % of nickel. 
     
     
         23 . The composition of  claim 20 , wherein the composition comprises at least 0.5 wt % of boron. 
     
     
         24 . A thermally sprayed coating on a substrate, comprising:
 a coating of thermally sprayed metallic material on a substrate,   wherein the coating is formed by one or more layers of metallic material   
       that comprises the following components:
 about 0.2 wt % to about 2.0 wt % of carbon; 
 about 0.2 wt % to about 2.0 wt % of nitrogen; and 
 about 0.1 wt % to about 7.0 wt % of boron, 
 with iron being a principal remaining element of the composition. 
 
     
     
         25 . The coating of  claim 24 , wherein the metallic material comprises the following composition:
 about 0.3 wt % to 1.15 wt % of carbon;   about 0.3 wt % to 1.15% nitrogen; and   at least 0.5 wt % of boron.   
     
     
         26 . The coating of  claim 24 , wherein the substrate is a downhole component. 
     
     
         27 . The coating of  claim 24 , wherein the substrate is a band on a tubular. 
     
     
         28 . The coating of  claim 24 , wherein the substrate is a downhole rotor. 
     
     
         29 . A method for applying a coating to a substrate, comprising:
 thermally spraying metallic material on an external surface of a substrate to form a thermal spray layer on the substrate, wherein the material, at least prior to being sprayed, comprises the following components:   about 0.2 wt % to about 2.0 wt % of carbon;   about 0.2 wt % to about 2.0 wt % of nitrogen; and   about 0.1 wt % to about 7.0 wt % of boron,   with iron being a principal remaining element of the composition.   
     
     
         30 . The method of  claim 29 , wherein the substrate is a downhole component. 
     
     
         31 . The method of  claim 29 , wherein the substrate is a band on a tubular. 
     
     
         32 . The method of  claim 29 , wherein the substrate is a downhole component.