Coating/repairing process using electrospark with psp rod

Abstract

An electrospark deposition electrode and an associated method for depositing coatings using the electrode are provided. The electrode includes a powder of a first metal and a powder of a second metal. The second metal is a braze alloy including nickel, the second metal having a lower melting point than the first metal. The powder of the first metal and the powder of the second metal are sintered together to form the electrode so that the powders are comingled but not combined within the electrode. The method includes depositing a layer of the first metal onto the substrate using an electrospark deposition process.

What is claimed is: 
     
         1 . An electrospark deposition electrode including:
 a powder of a first metal; and   a powder of a second metal, wherein the second metal is a braze alloy including nickel, the powder of the second metal having a lower melting point than the first metal,   wherein the powder of the first metal and the powder of the second metal are sintered together to form the electrospark deposition electrode so that the powder of the first metal and the powder of the second metal are comingled but not combined within the electrospark deposition electrode.   
     
     
         2 . The electrospark deposition electrode according to  claim 1 , wherein the first metal is a superalloy. 
     
     
         3 . The electrospark deposition electrode according to  claim 2 , wherein the superalloy includes a base alloying element of nickel. 
     
     
         4 . The electrospark deposition electrode according to  claim 2 , wherein the superalloy includes a base alloying element of cobalt. 
     
     
         5 . The electrospark deposition electrode according to  claim 2 , wherein the electrospark deposition electrode contains about 60% superalloy and about 40% of the second metal. 
     
     
         6 . The electrospark deposition electrode according to  claim 2 , wherein the electrospark deposition electrode contains a maximum of 90% of the second metal. 
     
     
         7 . The electrospark deposition electrode according to  claim 2 , wherein the particle sizes of the superalloy and the second metal are in the range between about 325 mesh (44 microns) and about 120 mesh (125 microns). 
     
     
         8 . A method for the deposition of a coating on a substrate including:
 providing a substrate;   providing an electrospark deposition electrode, wherein the electrospark deposition electrode includes a powder of a first metal, a powder of a second metal, wherein the second metal is a braze alloy including nickel, the powder of the second metal having a lower melting point than the first metal, wherein the powder of the first metal and the powder of the second metal are sintered together to form the electrospark deposition electrode so that the powder of the first metal and the powder of the second metal are comingled but not combined within the electrospark deposition electrode; and   depositing a layer of the first metal onto the substrate using an electrospark deposition process.   
     
     
         9 . The method according to  claim 8 , further including the step of depositing an amount of the second metal onto the substrate. 
     
     
         10 . The method according to  claim 9 , wherein the step of depositing an amount of the second metal onto the substrate further includes depositing a lower ratio of the second metal to the first metal onto the substrate than the ratio of the second metal to the first metal present within the electrospark deposition electrode. 
     
     
         11 . The method according to  claim 8 , wherein the step of depositing a layer of the first metal onto the substrate using an electrospark deposition process includes creating a deposited layer with relatively low surface roughness. 
     
     
         12 . The method according to  claim 11 , wherein the deposited layer has a surface roughness less than about 2.01 μm. 
     
     
         13 . The method according to  claim 8 , wherein the step of depositing a layer of the first metal onto the substrate using an electrospark deposition process includes conducting the electrospark deposition process in an atmosphere of an inert gas. 
     
     
         14 . The method according to  claim 13 , wherein the inert gas is argon.