Segmented thermal barrier coating and method of manufacturing the same

Abstract

A thermal barrier coating (18) having a less dense bottom layer (20) and a more dense top layer (22) with a plurality of segmentation gaps (28) formed in the top layer to provide thermal strain relief. The top layer may be at least 95% of the theoretical density in order to minimize the densification effect during long term operation, and the bottom layer may be no more than 95% of the theoretical density in order to optimize the thermal insulation and strain tolerance properties of the coating. The gaps are formed by a laser engraving process controlled to limit the size of the surface opening to no more than 50 microns in order to limit the aerodynamic impact of the gaps for combustion turbine applications. The laser engraving process is also controlled to form a generally U-shaped bottom geometry (54) in the gaps in order to minimize the stress concentration effect.

Dependencies are inferred from the claim text.