Erosion and corrosion resistant components and methods thereof

Abstract

A coating system and a method of applying the coating system on an article. The coating system includes a sacrificial coating on a surface of the article and an erosion-resistant coating on the sacrificial coating, wherein the erosion-resistant coating comprises a layer of a polymeric material. The sacrificial coating is more anodic than the surface or the erosion-resistant coating.

1 . A coating system for an article, the coating system comprising:
 a sacrificial coating deposited on a surface of the article; and   an erosion-resistant coating deposited on the sacrificial coating comprising a layer of a polymeric material, wherein the sacrificial coating is more anodic than both the surface and the erosion-resistant coating.   
     
     
         2 . The coating system of  claim 1 , wherein the article comprises a stainless steel or a superalloy. 
     
     
         3 . The coating system of  claim 1 , wherein the sacrificial coating comprises a layer of Al, Cr, Zn, an Ni—Al alloy, an Al—Si alloy, an Al-based alloy, a Cr-based alloy or a Zn-based alloy, an Al polymer composite, or a combination thereof. 
     
     
         4 . The coating system of  claim 1 , wherein the sacrificial coating comprises a layer of a conductive undercoat and a layer of an overcoat disposed on the undercoat, the overcoat comprising an inorganic matrix binder having a plurality of ceramic particles and conductive particles embedded therein. 
     
     
         5 . The coating system of  claim 1 , wherein the polymeric material of the erosion-resistant coating comprises siloxanes, silicon alkyds, and flurosilicones, modified bituminous materials, modified tar, epoxy-based materials, elastomers, polybutadiene, neoprene, butyl rubber, or a combination thereof. 
     
     
         6 . The coating system of  claim 1 , further comprising a primer material layer between the sacrificial coating and the erosion-resistant coating. 
     
     
         7 . The coating system of  claim 1 , wherein the article is a compressor blade of a gas turbine. 
     
     
         8 . The coating system of  claim 1 , wherein the sacrificial coating has a thickness of about 5 to about 50 micrometers. 
     
     
         9 . The coating system of  claim 1 , wherein the erosion-resistant coating has a thickness of about 50 to about 125 micrometers. 
     
     
         10 . The article comprising the coating system of  claim 1  thereon. 
     
     
         11 . A method of applying a coating system on an article, the method comprising:
 depositing a sacrificial coating on a surface of the article; and then   depositing an erosion-resistant coating on the sacrificial coating, the erosion-resistant coating comprising a layer of a polymeric material, wherein the sacrificial coating is more anodic than the surface of the article or the erosion-resistant coating.   
     
     
         12 . The method of  claim 11 , wherein depositing the sacrificial coating produces a residual compressive stress in the sacrificial coating. 
     
     
         13 . The method of  claim 11 , wherein the surface of the article is defined by a substrate formed of a stainless steel or a superalloy. 
     
     
         14 . The method of  claim 11 , wherein the sacrificial coating comprises a layer of Al, Cr, Zn, an Ni—Al alloy, an Al—Si alloy, an Al-based alloy, a Cr-based alloy or a Zn-based alloy, an Al polymer composite, or a combination thereof. 
     
     
         15 . The method of  claim 11 , wherein the sacrificial coating comprises a layer of a conductive undercoat and a layer of an overcoat disposed on the undercoat, the overcoat comprising an inorganic matrix binder having a plurality of ceramic particles and conductive particles embedded therein. 
     
     
         16 . The method of  claim 11 , wherein the polymeric material of the erosion-resistant coating comprises siloxanes, silicon alkyds, and flurosilicones, modified bituminous materials, modified tar, epoxy-based materials, elastomers, polybutadiene, neoprene, butyl rubber, or a combination thereof. 
     
     
         17 . The method of  claim 11 , further comprising depositing a primer material layer between the sacrificial coating and the erosion-resistant coating prior to depositing the erosion-resistant coating. 
     
     
         18 . The method of  claim 11 , wherein the article is a compressor blade of a gas turbine. 
     
     
         19 . The method of  claim 11 , wherein the sacrificial coating has a thickness of about 5 to about 50 micrometers. 
     
     
         20 . The method of  claim 11 , wherein the erosion-resistant coating has a thickness of about 50 to about 125 micrometers.