Additive manufacturing of thermally sprayed layers for wear and corrosion resistance

Abstract

A thermal spray alloy system is disclosed that is more resistant to corrosion and wear than conventional thermally sprayed coatings. The alloy system utilizes layers of different alloys to provide increased wear and corrosion resistance. The disclosed alloy addresses issues of wear and corrosion by utilizing a copper-based alloy as one thermally sprayed layer and an iron-based alloy as a second thermally sprayed layer via twin wire arc spray application processes, as is known in the art. The first layer may be about 50.0 wt % to about 95.0 wt % of copper. Between 2-10 applications of each layer may be applied to a substrate.

What is claimed is: 
     
         1 . A thermally sprayed coating on a substrate, comprising:
 a first layer of thermally sprayed metallic material on a substrate, wherein the first layer is formed by a first metallic material that comprises about 50.0 wt % to about 95.0 wt % of copper; and   a second layer of thermally sprayed metallic material on the substrate, wherein the second layer is formed by a second metallic material that comprises substantially iron.   
     
     
         2 . The coating of  claim 1 , wherein the coating comprises a plurality of layers comprising at least two layers of the first metallic material and at least two layers of the second metallic material. 
     
     
         3 . The coating of  claim 1 , wherein the first layer provides corrosion resistance to the substrate and the second layer provides wear resistance to the substrate. 
     
     
         4 . The coating of  claim 1 , wherein the first metallic material is formed of the aluminum bronze alloy. 
     
     
         5 . The coating of  claim 1 , wherein the first metallic material is formed from a cored wire that utilizes a coper alloy strip encasing a powdered core. 
     
     
         6 . The coating of  claim 1 , wherein the metallic material forming the first layer comprises the following composition:
 about 50.0 wt % to about 90.0 wt % of copper;   about 4.0 wt % to about 30.0 wt % of aluminum;   about 0.0 wt % to about 30.0 wt % of nickel;   about 0.0 wt % to about 5.0 wt % of boron;   about 0.0 wt % to about 6.0 wt % of silicon; and   about 0.0 wt % to about 1.0 wt % of carbon.   
     
     
         7 . The coating of  claim 1 , wherein the coating comprises an alternating plurality of layers formed of the first metallic material and the second metallic material. 
     
     
         8 . The coating of  claim 1 , wherein each of the first and second layers is between 0.010″ and 0.10″ thick. 
     
     
         9 . The coating of  claim 1 , wherein the substrate is a downhole component. 
     
     
         10 . The coating of  claim 1 , wherein the substrate is a band on a tubular. 
     
     
         11 . The coating of  claim 1 , wherein the substrate is a blade on a tubular. 
     
     
         12 . A method for applying a coating to a substrate, comprising:
 thermally spraying a plurality of different layers on an external surface of a substrate by twin wire arc spray;   wherein a first layer of the plurality of different layers comprises a copper based alloy from a first metallic material,   wherein a second layer of the plurality of different layers comprises an iron based alloy from a second metallic material.   
     
     
         13 . The method of  claim 12 , wherein the first metallic material comprises the following composition:
 about 50.0 wt % to about 90.0 wt % of copper;   about 4.0 wt % to about 30.0 wt % of aluminum;   about 0.0 wt % to about 30.0 wt % of nickel;   about 0.0 wt % to about 5.0 wt % of boron;   about 0.0 wt % to about 6.0 wt % of silicon; and   about 0.0 wt % to about 1.0 wt % of carbon.   
     
     
         14 . The method of  claim 12 , wherein the first metallic material is a cored wire, wherein the copper is located substantially within an outer sheath of the cored wire. 
     
     
         15 . The method of  claim 12 , wherein each of the plurality of layers comprises a thickness of between about 0.010 inches and 0.10 inches. 
     
     
         16 . The method of  claim 12 , wherein the plurality of layers comprises at least two layers of the first metallic material and at least two layers of the second metallic material.