Treated gas turbine components and processes of treating gas turbine systems and gas turbine components

Abstract

A process of treating a component includes mechanically removing surface debris from a base coating of the component, identifying at least one surface feature in the base coating, and applying an overlay coating layer over the surface feature of the base coating without stripping off the base coating. A process of treating a gas turbine component includes mechanically removing surface debris from a base coating of the gas turbine component, identifying at least one surface feature in the base coating of corrosion pits, dents, spalls, and combinations thereof, and applying an overlay coating layer over the surface feature of the base coating without stripping off the base coating. A treated gas turbine component includes a gas turbine component substrate and a base coating on the gas turbine component substrate having at least one healed surface feature. The healed surface feature includes an overlay coating layer on the base coating.

What is claimed is: 
     
         1 . A process of treating a component comprising:
 mechanically removing surface debris from a base coating of the component;   identifying at least one surface feature in the base coating; and   applying an overlay coating layer over the at least one surface feature of the base coating without stripping off the base coating.   
     
     
         2 . The process of  claim 1  wherein the applying comprises an applying technique that is the same as the applying technique used to apply the base coating. 
     
     
         3 . The process of  claim 1  wherein the applying comprises thermal spraying. 
     
     
         4 . The process of  claim 3  wherein the applying comprises selectively applying the overlay coating layer to cover the at least one surface feature. 
     
     
         5 . The process of  claim 1  wherein the overlay coating layer comprises a gel coating. 
     
     
         6 . The process of  claim 5  wherein the gel coating comprises a gel aluminide selectively applied to the at least one surface feature. 
     
     
         7 . The process of  claim 1  wherein the at least one surface feature comprises at least one corrosion pit and the applying comprises applying the overlay coating layer to the at least one corrosion pit and dissolving at least a portion of corrosion products present therein. 
     
     
         8 . The process of  claim 1  wherein the base coating comprises MCrAlY, wherein M is selected from the group consisting of nickel, cobalt, iron, alloys thereof, and combinations thereof. 
     
     
         9 . The process of  claim 1  wherein the component is a turbine component. 
     
     
         10 . The process of  claim 9  further comprising removing the turbine component from service in a turbine system. 
     
     
         11 . The process of  claim 1  further comprising heat treating the component after applying the overlay coating layer. 
     
     
         12 . The process of  claim 1  wherein the surface feature is selected from the group consisting of at least one corrosion pit, dent, spall, cavity, discontinuity, porosity defect, shrinkage defect, scratch, void, impurity-derived fault, or combinations thereof. 
     
     
         13 . A treated gas turbine component comprising:
 a gas turbine component substrate; and   a base coating on the gas turbine component substrate having at least one healed surface feature;   wherein the healed surface feature includes an overlay coating layer on at least one surface feature of the base coating.   
     
     
         14 . The treated gas turbine component of  claim 13  wherein the overlay coating layer comprises gel aluminide. 
     
     
         15 . The treated gas turbine component of  claim 13  wherein the healed surface feature includes dissolved corrosion products. 
     
     
         16 . The treated gas turbine component of  claim 13  wherein the base coating comprises MCrAlY, wherein M is selected from the group consisting of nickel, cobalt, iron, alloys thereof, and combinations thereof. 
     
     
         17 . The gas turbine component of  claim 13  wherein the gas turbine component is a turbine bucket. 
     
     
         18 . A process of treating a gas turbine component comprising:
 mechanically removing surface debris from a base coating of the gas turbine component;   identifying at least one surface feature in the base coating selected from the group consisting of at least one corrosion pit, dent, spall, cavity, discontinuity, porosity defect, shrinkage defect, scratch, void, impurity-derived fault, or combinations thereof; and   applying an overlay coating layer over the at least one surface feature of the base coating without stripping off the base coating.   
     
     
         19 . The process of  claim 18  wherein the applying comprises thermal spraying. 
     
     
         20 . The process of  claim 18  wherein the overlay coating layer comprises a gel coating. 
     
     
         21 . The process of  claim 20  wherein the gel coating comprises a gel aluminide selectively applied to the at least one surface feature. 
     
     
         22 . The process of  claim 18  wherein the applying comprises applying the overlay coating layer to at least one corrosion pit and dissolving at least a portion of corrosion products present therein.