Abstract
In this study, a thermal barrier coating (TBC) was applied to a 4th generation Ni-based single crystal superalloy TMS-138 and its spallation life in thermal cycling condition at 1135°C was compared with the case of CMSX-4 substrate. Pt-modified nickel aluminide coating was applied as bond coat and yttria-stabilized zirconia prepared by electron beam physical vapor deposition was applied as topcoat.
The spallation lives of TBCs on TMS-138 substrate were 700-1000cycles and longer than that of TBCs on CMSX-4 substrate. In TBCs on TMS-138 substrate, the ratcheting at bondcoat surface hasn't grown up with increased thermal cycle and it was different from the case of TBCs on CMSX-4 substrate. It was suggested that creep strength of bondcoat was increased and put retains the rumpling in Ru-bearing TMS-138 alloy.
