A metallic article having a thermal barrier coating and a method of application thereof

摘要

A metallic article (30) comprises a bond coating (34) on the metallic article (30) and a ceramic thermal barrier coating (38) on the bond coating (34). The ceramic thermal barrier coating (38) comprises a plurality of columnar grains (40) which extend perpendicularly to the surface of the metallic article (30). Each columnar grain (40) has a plurality of layers (42,44). Some of the layers (44) have sub-grains (48) extending at an acute angle to the surface of the metallic article (30) to form voids (50) between adjacent sub-grains (48). The voids (50) are arranged at an acute angle to the surface of the metallic article (30) and thereby reduce the thermal conductivity of the ceramic thermal barrier coating (38). Some of the layers (42) have sub-grains (46) extending perpendicularly to the surface of the metallic article (30) to provide erosion resistance.