Coated silicon comprising material for protection against environmental corrosion

Abstract

In accordance with an embodiment of the invention, an article is disclosed. The article comprises a gas turbine engine component substrate comprising a silicon material; and an environmental barrier coating overlying the substrate, wherein the environmental barrier coating comprises cerium oxide, and the cerium oxide reduces formation of silicate glass on the substrate upon exposure to corrodant sulfates.

1 - 14 . (canceled) 
     
     
         15 . A method of reducing silicate glass formation on a gas turbine engine component comprising:
 providing a substrate of the gas turbine engine component, wherein the substrate comprises a silicon material; and   depositing cerium oxide directly on the substrate or admixing cerium oxide with the silicon material of the substrate; wherein the cerium oxide reduces formation of silicon glass on the substrate upon exposure to corrodant sulfates.   
     
     
         16 . A method of reducing silicate glass formation on a gas turbine engine component comprising:
 providing a substrate of the gas turbine engine component, wherein the substrate comprises a silicon material;   depositing a bond layer comprising a silicon material and overlying the substrate;   depositing a first layer comprising mullite and overlying the bond layer;   depositing a second layer comprising barium strontium aluminosilicate overlying the first layer; and   depositing a layer consisting of cerium oxide overlying second layer or admixing cerium oxide with the barium strontium aluminosilicate; wherein the cerium oxide reduces formation of silicon glass on the substrate upon exposure to corrodant sulfates.   
     
     
         17 . The method of  claim 16 , wherein each layer is deposited by a method selected from the group consisting of: air plasma spray, vacuum plasma spray, chemical vapor deposition and high velocity oxy fuel.