Initiation and Propagation of Debonding Crack in A TBC under Cyclic Loading

Abstract

Propagation of naturally initiated debonding crack in the themal barrier coating (TBC) which consitsted of Ni-base superalloy substrate, CoNiCrAlY bond coat, and 8% yttria stabilized zirconia, was investigated at room and high temperatures, when it was subjected to cyclic loading. Special foucus was put on the understanding of the crack initiation and propagation mechanisms.