Coatings for turbine parts

Abstract

A method and a turbine part having a coating with a matrix layer that includes a high temperature resistant hydrophobic polysiloxane filler, wherein the coating has superior mechanical strength and temperature resistance.

1 . A coating for axially rotating machine part that in use is subject to water laden gas, the coating having a metal matrix comprising polysiloxane filler distributed throughout a thickness of the coating. 
     
     
         2 . The coating of  claim 1  wherein the particles are homogenously distributed throughout the thickness of the coating. 
     
     
         3 . The coating of  claim 1  wherein the metal matrix comprises Nickel or alloys thereof. 
     
     
         4 . The coating of  claim 1  wherein the filler has the form of particles. 
     
     
         5 . The coating of  claim 6  wherein the particles have a size distribution as measured by laser diffraction of d10=0.37 micrometres, D50=1.07 micrometres and D90=2.31 micrometres. 
     
     
         6 . The coating of  claim 1  wherein the filler comprises between 5 to 50 volume % of the coating. 
     
     
         7 . The coating of  claim 1  wherein the filler comprises between 25 to 45 volume % of the coating, more preferably between 35 to 45 volume % of the coating. 
     
     
         8 . The coating of  claim 1  comprising a corrosion resistance inner layer free of the filler and the metal matrix forms an outer layer of the coating. 
     
     
         9 . The coating of  claim 1  wherein the part is an airfoil of a steam turbine. 
     
     
         10 . The coating of  claim 1  wherein the part is an airfoil of a gas compressor or of a gas turbine. 
     
     
         11 . A method for coating a part for an axially rotating machine with an erosion resilience and coating, the method comprising:
 providing a part of an axially rotating machine;   coating the part with a coating comprising a metal matrix with a polysiloxane filler distributed throughout a thickness of the metal matrix; and   stoving the filler to as to change the temperature resistance of the polysiloxane filler.   
     
     
         12 . The method of  claim 11  wherein the stoving is performed before the step of coating of the part. 
     
     
         13 . The method of  claim 11  wherein the stoving step is performed after the coating step. 
     
     
         14 . The method of  claim 11  wherein the method of coating includes electrolytic nickel plating and/or electroless chemical coating.