Preparation and Properties of Sm2Zr2O7 Ceramics for Thermal Barrier Coatings by APS

Material of Sm2Zr2O7 composition powder was synthesized by coprecipitation method using Sm2O3 and ZrOCl2•8H2O as raw materials, and applied as ceramic topcoats of thermal barrier coating (TBC) by atmospheric plasma spraying (APS). The ceramics powder was prepared with proper distribution of particle size about 30-70μm by spray-dried method. Phase analyses revealed that Sm2Zr2O7 coatings keeping the single phase with pyrochlore structure before and after the thermal cycling test. The thermally grown oxide at the topcoat-bondcoat interface and the formation of transverse crack were the major factors that lead to the coating failure on thermal cycling.