Large deformation simulations of cyclic displacement instabilities in thermal barrier systems

The cyclic displacement instability exhibited by a thermally grown oxide (TGO) in a thermal barrier system has been simulated using a scheme that embodies large-scale thickening. The investigation has three main objectives. (i) A sensitivity study that probes the influence of the thermo-mechanical properties of the bond coat. It uses properties that closely resemble those relevant to actual bond coat materials. (ii) Explore the influence of the size of the imperfections present on the bond coat surface and address the critical size below which the instability is suppressed. (iii) A determination of the influence of TGO growth kinetics ranging between linear and parabolic.