Thermal barrier coating system having a top coat with a graded interface

摘要

The invention provides an improved thermal barrier coating system for a hot section component. The thermal barrier coating has a metallic bond coat and a ceramic top coat made of two constituents. The top coat is formed so that there is provided a graded interface between the monolithic layers of the two top coat constituents. This allows an increase in overall thickness of the thermal barrier coating which provides a higher thermal insulation for the component being protected.