Effects of Ce and Si Addition to CoNiCrAlY Bond-Coat Materialon Oxidation Behavior and Bonding Strength of Thermal Barrier Coatings

摘要

In thermal barrier coating (TBC) system, thermally grownoxide (TGO) forms at the interface between the top-coat andbond-coat during service. Delamination or spallation at theinterface can be occurred by the TGO formation and growth.Therefore, Modifications of the bond-coat materials are onemeans to inhibit the TGO formation and to improve thebonding strength of TBCs. In this study, morphologies ofTGO were controlled by using Ce and Si addition toconventional CoNiCrAlY bond-coat material. As a result,when the TBCs with Ce added bond-coat materials were agedat 1373K for 100 hours, morphologies of TGO were changeddrastically. It is expected that the morphologies can improvebonding strength of TBCs. We carried out to evaluate thebonding strength by using four-point bending tests. As a result,TBC coated with Ce added bond-coat materials indicatedexcellent bonding strength.