Plasma spraying process

Abstract

The application relates to a process for producing a coating by thermal spraying, in particular by plasma spraying, in which a component, in particular a cylinder liner, is internally coated with an alloy. It is proposed that nitrogen is fed as transporting gas, a spraying additive being a solid alloy wire which is guided into a plasma stream, and coating being performed without additional powder.

1 . A process for producing a coating by thermal spraying including by plasma spraying, comprising:
 coating with an alloy a component, wherein   nitrogen gas is fed at least as transporting gas, a spraying additive being a solid alloy wire which is guided into a plasma stream, and coating being performed without additional powder.   
     
     
         2 . The process as claimed in  claim 1 , wherein
 the plasma spraying is a PTWA coating process, and wherein the component is a cylinder bearing surface.   
     
     
         3 . The process as claimed in  claim 1 , wherein
 the additional spraying wire is an iron alloy comprising 12 to 35% by weight Cr, 2-10% by weight Al, 0-1% by weight Si, 0-1% by weight Mn, 0-1% by weight C.   
     
     
         4 . The process as claimed in  claim 3 , wherein the iron alloy further comprises constituents including 0-1% by weight P, 0-0.09% by weight S, 0-5% by weight Mo, 0-1% by weight Ni, 0-0.5% by weight Cu, 0-0.5% by weight N, and a remainder Fe. 
     
     
         5 . The process as claimed in  claim 1 , wherein
 the additional spraying wire is an iron alloy comprising 23% by weight Cr, 5% by weight Al, less than 0.5% by weight Si, less than 0.2% by weight Mn, less than 0.05% by weight C, and remaining constituents having a proportion of less than 2% by weight, a remainder being iron.   
     
     
         6 . The process as claimed in  claim 1 , wherein the component is an internal combustion engine component. 
     
     
         7 . The process as claimed in  claim 6 , wherein the component is cast aluminum. 
     
     
         8 . The process as claimed in  claim 6 , wherein the transporting gas is air. 
     
     
         9 . The process as claimed in  claim 6 , wherein the solid alloy wire is homogeneous. 
     
     
         10 . The process as claimed in  claim 6 , further comprising operating the engine with ethanol containing fuel. 
     
     
         11 . A process, comprising:
 producing a coating by thermal spraying, including by plasma spraying, including coating an engine cylinder bearing surface with an alloy, where nitrogen gas is fed at least as transporting gas, a spraying additive being a solid alloy wire which is guided into a plasma stream, and coating being performed without additional powder, wherein the plasma spraying is a PTWA coating process.   
     
     
         12 . The process as claimed in  claim 11 , wherein the cylinder bearing surface is cast aluminum, the engine being configured to combust ethanol-containing fuel. 
     
     
         13 . The process as claimed in  claim 12 , wherein the transporting gas is air. 
     
     
         14 . The process as claimed in  claim 13 , wherein the solid alloy wire is homogeneous. 
     
     
         15 . The process as claimed in  claim 14 , further comprising operating the engine with ethanol-containing fuel.