EFFECT OF PRE-OXIDATION TREATMENT ON THE DEVELOPMENT OF THERMALLY GROWN OXIDE

摘要

This paper examines the effects of pre-oxidation treatments on the growth rate of thermally grown oxide (TGO) in an atmospheric plasma sprayed (APS) thermal barrier coating (TBC) system. A MCrAlY bond coat and yttria-stabilized zirconia (YSZ) top coat were used, and the pre-oxidation treatments employed were low pressure oxidation treatment (LPOT) and vacuum heat treatment (VHT). Treated samples were subjected to isothermal exposures at 1050°C for up to 1000 hours. Subsequent microstructural evaluations revealed that the TGO growth rate and interfacial cracking were both significantly reduced by the pre-oxidation treatment, demonstrating the potential for such treatments to extend the service lives of APS TBC systems.