Yttrium aluminum garnet based thermal barrier coatings

Abstract

A multi-layer coating that allows arrest of contaminant infiltration includes at least one layer that is not very reactive to an infiltrating reactive species, and at least one highly reactive ceramic layer (HRC layer) containing materials that react to slow or arrest contaminant infiltration.

What is claimed is: 
     
         1 . A multi-layer coating that allows arrest of contaminant infiltration comprising:
 at least one layer that is not very reactive to an infiltrating reactive species, and   at least one highly reactive ceramic layer (HRC layer) containing materials that react to slow or arrest contaminant infiltration.   
     
     
         2 . The multi-layer coating of  claim 1 , wherein the HRC layer comprises one or more oxides of Y and/or one or more oxides of any lanthanide (La, Ce, Pr, Nd, Pm, SM, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu). 
     
     
         3 . The multi-layer coating of  claim 1 , comprising one or more inert layers or phases and one or more reactive layers or phases. 
     
     
         4 . The multi-layer coating of  claim 1 , wherein the coating comprises at least two layers of yttrium aluminum garnet (YAG) and a layer comprising Y 2 O 3  between at least two layers of YAG. 
     
     
         5 . The multi-layer coating of  claim 1 , wherein the coating comprises at least two layers of YAG, and a layer of Gd 2 Zr 2 O 7  between at least two layers of YAG; and another layer of YAG between at least two layers of YAG and also between the layers comprising Y 2 O 3  and Gd 2 Zr 2  O 7 . 
     
     
         6 . The multi-layer coating of  claim 1 , wherein the coating comprises a first layer that includes Y 2 O 3  and Gd 2 Zr 2 O 7  between layers of YAG and a second layer of Y 2 O 3 +Gd 2 Zr 2  O 7  between layers of YAG. 
     
     
         7 . The multi-layer coating of  claim 1  comprising more than one inert layer and more than one reactive layer. 
     
     
         8 . The multi-layer coating of  claim 1 , wherein the coating is made by the solution precursor plasma spray process. 
     
     
         9 . The multi-layer coating of  claim 1 , wherein the coating is used as a thermal barrier coating. 
     
     
         10 . The multi-layer coating of  claim 1 , wherein the coating is applied on at least one gas turbine hot section component. 
     
     
         11 . A method of fabricating a multi-layer coating that allows arrest of contaminant infiltration comprising:
 depositing at least one layer that comprises materials that is not very reactive to an infiltrating reactive species, and   depositing at least one highly reactive ceramic layer (HRC layer) containing at least one material that react to slow or arrest contaminant infiltration.   
     
     
         12 . The method of  claim 11 , wherein the HRC layer comprises one or more oxides of Y and/or one or more oxides of any lanthanide (La, Ce, Pr, Nd, Pm, SM, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu). 
     
     
         13 . The method of  claim 11 , wherein one or more inert layers or phases and one or more reactive layers or phases are deposited. 
     
     
         14 . The method  claim 11  wherein the method includes depositing at least two layers of YAG, depositing a layer comprising Y 2 O 3  between at least two layers of YAG; a layer of Gd 2 Zr 2  O 7  between at least two layers of YAG; and depositing another layer of YAG between at least two layers of YAG and also between the layers comprising Y 2 O 3  and Gd 2 Zr 2 O 7 . 
     
     
         15 . The method of  claim 11 , wherein the method includes depositing a first layer of Y 2 O 3 +Gd 2 Zr 2 O 7  between layers of YAG and depositing a second layer of Y 2 O 3 +Gd 2 Zr 2 O 7  between layers of YAG. 
     
     
         16 . The method of  claim 11 , wherein the method includes depositing more than one inert layer and more than one reactive layer. 
     
     
         17 . The method of  claim 11 , wherein at least one layer is deposited using plasma spray processes. 
     
     
         18 . The method of  claim 11 , wherein at least one layer is deposited using the solution plasma spray process. 
     
     
         19 . The method of  claim 11 , wherein the coating fabricated is a thermal barrier coating. 
     
     
         20 . The method of  claim 11 , wherein the coating fabricated is deposited on a gas turbine hot section component.