Thermal barrier coating for gas turbine engine components

Abstract

A thermal barrier coating for a substrate that has a major surface. The thermal barrier coating comprises: a bond coat layer disposed on the major surface of the substrate; a thermally grown oxide (TGO) layer disposed on the bond coat layer; and a top coat layer disposed on the TGO layer. The top coat layer comprises a ceramic top coat material that comprises: a matrix phase comprising at least one compound of formula ABO 4 , AB 3 O 7 or AB 3 O 9 , where A is a rare-earth element, B is selected from the group consisting of niobium and tantalum, and O is oxygen; and an inclusion phase that is dispersed in the matrix phase and comprising one or more of alumina and a compound of formula A 3 AlO 12 , AAlO 3 or A 4 Al 2 O 9 , where A is a rare-earth element, Al is aluminium, and O is oxygen.

We claim: 
     
         1 . A thermal barrier coating for a substrate that has a major surface, the thermal barrier coating comprises:
 a bond coat layer disposed on the major surface of the substrate;   a thermally grown oxide (TGO) layer disposed on the bond coat layer; and   a top coat layer disposed on the TGO layer, the top coat layer comprising a ceramic top coat material comprising:
 a matrix phase comprising at least one compound of formula ABO 4 , AB 3 O 7  or AB 3 O 9 , where A is a rare-earth element, B is selected from the group consisting of niobium and tantalum, and O is oxygen; and 
 an inclusion phase dispersed in the matrix phase and comprising one or more of alumina and a compound of formula AsAlO 12 , AAlO 3  or A 4 Al 2 O 9 , where A is a rare-earth element, Al is aluminium, and O is oxygen. 
   
     
     
         2 . The thermal barrier coating of  claim 1 , wherein the ceramic top coat material comprises: (1) a matrix phase that comprises at least one of LaNbO 4 , CeNbO 4 , PrNbO 4 , NdNbO 4 , PmNbO 4 , SmNbO 4 , EuNbO 4 , GdNbO 4 , TbNbO 4 , DyNbO 4 , HoNbO 4 , ErNbO 4 , TmNbO 4 , YbNbO 4 , LuNbO 4 , ScNbO 4 , YNbO 4 . LaNb 3 O 7 , CeNb 3 O 7 , PrNb 3 O 7 , NdNb 3 O 7 , PmNb 3 O 7 , SmNb 3 O 7 , EuNb 3 O 7 , GdNb 3 O 7 , TbNb 3 O 7 , DyNb 3 O 7 , HoNb 3 O 7 , ErNb 3 O 7 , TmNb 3 O 7 , YbNb 3 O 7 , LuNb 3 O 7 , ScNb 3 O 7 , YNb 3 O 7 . LaNb 3 O 9 , CeNb 3 O 9 , PrNb 3 O 9 , NdNb 3 O 9 , PmNb 3 O 9 , SmNb 3 O 9 , EuNb 3 O 9 , GdNb 3 O 9 , TbNb 3 O 9 , DyNb 3 O 9 , HoNb 3 O 9 , ErNb 3 O 9 , TmNb 3 O 9 , YbNb 3 O 9 , LuNb 3 O 9 , ScNb 3 O 9 , and YNb 3 O 9 ,; and (2) an inclusion phase that is dispersed in the matrix phase and comprises one or more of alumina, LasAl 5 O 12 , Ce 3 Al 5 O 12 , Pr 3 Al 5 O 12 , Nd 3 Al 5 O 12 , Pm 3 Al 5 O 12 , Sm 3 Al 5 O 12 , Eu 3 Al 5 O 12 , Gd 3 Al 5 O 12 , Tb 3 Al 5 O 12 , Dy 3 Al 5 O 12 , Ho 3 Al 5 O 12 , Er 3 Al 5 O 12 , Tm 3 Al 5 O 12 , Yb 3 Al 5 O 12 , Lu 3 Al 5 O 12 , Sc 3 Al 5 O 12 , Y 3 Al 5 O 12 , LaAlO 3 , CeAlO 3 , PrAlO 3 , NdAlO 3 , PmAlO 3 , SmAlO 3 , EuAlO 3 , GdAlO 3 , TbAlO 3 , DyAlO 3 , HoAlO 3 , ErAlO 3 , TmAlO 3 , YbAlO 3 , LuAlO 3 , SCAlO 3 , YAlO 3 . La 4 Al 2 O 9 , Ce 4 Al 2 O 9 , Pr 4 Al 2 O 9 , Nd 4 Al 2 O 9 , Pm 4 Al 2 O 9 , Sm 4 Al 2 O 9 , Eu 4 Al 2 O 9 , Gd 4 Al 2 O 9 , Tb 4 Al 2 O 9 , Dy 4 Al 2 O 9 , HO 4 Al 2 O 9 , Er 4 Al 2 O 9 , Tm 4 Al 2 O 9 , Yb 4 Al 2 O 9 , Lu 4 Al 2 O 9 , SC 4 Al 2 O 9 , and Y 4 Al 2 O 9 . 
     
     
         3 . The thermal barrier coating of  claim 1 , wherein the ceramic top coat material comprises: (1) a matrix phase that comprises at least one of LaTaO 4 , CeTaO 4 , PrTaO 4 , NdTaO 4 , PmTaO 4 , SmTaO 4 , EuTaO 4 , GdTaO 4 , TbTaO 4 , DyTaO 4 , HoTaO 4 , ErTaO 4 , TmTaO 4 , YbTaO 4 , LuTaO 4 , ScTaO 4 , YTaO 4 , LaTa 3 O 7 , CeTasO 7 , PrTa 3 O 7 , NdTa 3 O 7 , PmTa 3 O 7 , SmTa 3 O 7 , EuTasO 7 , GdTa 3 O 7 , TbTa 3 O 7 , DyTa 3 O 7 , HoTasO 7 , ErTa 3 O 7 , TmTa 3 O 7 , YbTa 3 O 7 , LuTa 3 O 7 , ScTa 3 O 7 , YTa 3 O 7 , LaTa 3 O 9 , CeTa 3 O 9 , PrTa 3 O 9 , NdTa 3 O 9 , PmTa 3 Og, SmTa 3 O 9 , EuTa 3 O 9 , GdTa 3 O 9 , TbTa 3 O 9 , DyTa 3 O 9 , HoTasO 9 , ErTa 3 O 9 , TmTasO 9 , YbTasO 9 , LuTa 3 O 9 , ScTasOg, and YTasO 9 ; and (2) an inclusion phase that is dispersed in the matrix phase and comprises one or more of alumina, LasAl 5 O 12 , Ce 3 Al 5 O 12 , Pr 3 Al 5 O 12 , NdsAl 5 O 12 , Pm 3 Al 5 O 12 , Sm 3 Al 5 O 12 , Eu 3 Al 5 O 12 , Gd 3 Al 5 O 12 , Tb 3 Al 5 O 12 , Dy 3 Al 5 O 12 , Ho 3 Al 5 O 12 , Er 3 Al 5 O 12 , Tm 3 Al 5 O 12 , Yb 3 Al 5 O 12 , Lu 3 Al 5 O 12 , Sc 3 Al 5 O 12 , Y 3 Al 5 O 12 , LaAlO 3 , CeAlO 3 , PrAlO 3 , NdAlO 3 , PmAlO 3 , SmAlO 3 , EuAlOs, GdAlO 3 , TbAlO 3 , DyAlO 3 , HoAlO 3 , ErAlO 3 , TmAlO 3 , YbAlO 3 , LuAlO 3 , SCAlO 3 , YAlO 3 . La 4 Al 2 O 9 , Ce 4 Al 2 O 9 , Pr 4 Al 2 O 9 , Nd 4 Al 2 O 9 , Pm 4 Al 2 O 9 , Sm 4 Al 2 O 9 , Eu 4 Al 2 O 9 , Gd 4 Al 2 O 9 , Tb 4 Al 2 O 9 , Dy 4 Al 2 O 9 , HO 4 Al 2 O 9 , Er 4 Al 2 O 9 , Tm 4 Al 2 O 9 , Yb 4 Al 2 O 9 , Lu 4 Al 2 O 9 , Sc 4 Al 2 O 9 , and Y 4 Al 2 O 9 . 
     
     
         4 . The thermal barrier coating of  claim 1 , wherein the ceramic top coat material comprises: (1) a matrix phase that comprises at least one of LaNbO 4 , GdNbO 4 , YNbO 4 , LaTaO 4 , GdTaO 4 , YTaO 4 . LaNb 3 O 7 , GdNb 3 O 7 , YNb 3 O 7 , LaTa 3 O 7 , GdTa 3 O 7 , YTa 3 O 7 , LaNb 3 O 9 , GdNb 3 O 9 , YNb 3 O 9 , LaTa 3 O 9 , GdTa 3 Og and YTa 3 O 9 ; and (2) an inclusion phase that is dispersed in the matrix phase and comprises alumina, LasAl 5 O 12 , Gd 3 Al 5 O 12 , Y 3 Al 5 O 12 , LaAlO 3 , GdAlO 3 , YAlO 3. La 4 Al 2 O 9 , Gd 4 Al 2 O 9 , and Y 4 Al 2 O 9 . 
     
     
         5 . The thermal barrier coating of  claim 1 , wherein the ceramic top coat material comprises: (1) a matrix phase that comprises at least one of LaNbO 4 , CeNbO 4 , PrNbO 4 , NdNbO 4 , PmNbO 4 , SmNbO 4 , EuNbO 4 , GdNbO 4 , TbNbO 4 , DyNbO 4 , HoNbO 4 , ErNbO 4 , TmNbO 4 , YbNbO 4 , LuNbO 4 , ScNbO 4  and YNbO 4 ; and (2) an inclusion phase that is dispersed in the matrix phase and comprises alumina. 
     
     
         6 . The thermal barrier coating of  claim 1 , wherein the ceramic top coat material comprises: (1) a matrix phase that comprises at least one of LaTaO 4 , CeTaO 4 , PrTaO 4 , NdTaO 4 , PmTaO 4 , SmTaO 4 , EuTaO 4 , GdTaO 4 , TbTaO 4 , DyTaO 4 , HoTaO 4 , ErTaO 4 , TmTaO 4 , YbTaO 4 , LuTaO 4 , ScTaO 4  and YTaO 4 ; and (2) an inclusion phase that is dispersed in the matrix phase and comprises alumina. 
     
     
         7 . The thermal barrier coating of  claim 1 , wherein the ceramic top coat material comprises: (1) a matrix phase that comprises at least one of LaNbO 4 , GdNbO 4 , YNbO 4 , LaTaO 4 , GdTaO 4  and YTaO 4 ; and (2) an inclusion phase that is dispersed in the matrix phase and comprises alumina. 
     
     
         8 . The thermal barrier coating of  claim 1 , wherein the ceramic top coat material comprises: (1) a matrix phase that comprises GdNbO 4 ; and (2) an inclusion phase that is dispersed in the matrix phase and comprises alumina. 
     
     
         9 . The thermal barrier coating of  claim 1 , wherein the matrix phase further comprises one or more compounds of formula ABO 7 , AB 3 O 3 , A 3 BO 7 , ABO 4 , A 3 BO 7  and AB 3 O 3 , where A is a rare-earth element, B is one or more element selected from the group consisting of niobium and tantalum, and O is oxygen;
 and/or the inclusion phase further comprises one or more compounds of formula AAlO 3 , where A is a rare-earth element, Al is aluminium, and O is oxygen.   
     
     
         10 . The thermal barrier coating of  claim 1 , wherein the ceramic top coat material includes at least 5 mol. % of the inclusion phase. 
     
     
         11 . The thermal barrier coating of  claim 1 , wherein the ceramic top coat material comprises from 90 to 95 mol. % of the matrix phase and from 5 to 10 mol. % of the inclusion phase. 
     
     
         12 . The thermal barrier coating of  claim 1 , wherein the matrix phase and the inclusion phase together form  100 % by weight of the ceramic top coat material. 
     
     
         13 . The thermal barrier coating of  claim 1 , wherein the bond coat layer comprises one or more of an alloy oxidation and corrosion-resistant metal alloy, aluminide and platinum aluminide. 
     
     
         14 . The thermal barrier coating of  claim 1 , wherein the TGO layer comprises alumina or aluminide oxides. 
     
     
         15 . A composite article comprising:
 a substrate that has a major surface; and   a thermal barrier coating of  claim 1  disposed on the major surface of the substrate.   
     
     
         16 . The composite article of  claim 15 , wherein the substrate is a gas turbine engine component formed from the group consisting of steels, alloys, superalloys, refractory metals, inter-metallics, and ceramic matrix composite materials. 
     
     
         17 . The composite article of  claim 16 , wherein the gas turbine engine component is a high pressure turbine blade or a high pressure nozzle guide vane. 
     
     
         18 . A method of manufacturing a composite article, the method comprising coating a substrate with a thermal barrier coating of  claim 1 . 
     
     
         19 . The method of  claim 18 , wherein the substrate is coated with the thermal barrier coating using at least one of electron-beam physical vapour deposition (EB-PVD), suspension plasma spraying (SPS), solution precursor plasma spraying (SPPS), air plasma spraying (APS), high-velocity oxygen fuel (HVOF) processing, and suspension HVOF (S-HVOF) processing.