Numerical simulation of displacement instabilities of surface grooves on an alumina forming alloy during thermal cycling oxidation

Displacement instability of the thermally grown oxide (TGO) is a fundamental source of failure in thermal barrier systems. In this work, a finite element analysis has been performed to analyze the displacement instability occurring at a heat resistant metal with superficial TGO subjected to thermal cycling. Lateral and in-plane growth of the TGO which happens during high temperature is simulated by means of material property change from the substrate metal to the TGO. Most of the material properties including the TGO growth are based on the results experimentally obtained in-house. Results of the finite element analyses agree well with the experimental observation, which proves the accuracy and validity of this simulation. The technique will be useful for future work on more complicated phenomena such as deformation under thermo-mechanical cycling. This paper was recommended for publication in revised form by Associate Editor Maenghyo Cho Jun Ding received his B.S. degree in Mechanical Engineering from Chongqing Institute of Technology, China, in 2000. He then received his M.S. degree from Chongqing University, China, in 2004. Currently a Ph. D candidate at the Graduate School of Mechanical Systems Engineering at Chonnam National University in Gwangju, Korea, he is mainly working on the theoretical and numerical analyses of mechanical behaviors of various materials. Feng-Xun Li received his B.S. degree from the Department of Mechanical Engineering of Yanbian University, China, in 2005. He then received his M.S. degree from Chonnam National University, Korea, in 2007. He is currently a Ph. D candidate at the Graduate School of Mechanical Systems Engineering at Chonnam National University in Gwangju, Korea and is mainly working on the deformation mechanism of thermally grown oxide. Ki-Ju Kang received his B.S. degree in Mechanical Engineering from Chonnam National University, Korea, in 1981. He then received his M.S. and Ph.D. degrees from Korea Advanced Institute of Science and Technology in 1983 and 1988, respectively. Dr. Kang is currently a Professor at the School of Mechanical Systems Engineering at Chonnam National University in Gwangju, Korea. His laboratory is designated as a national research laboratory. His research interests include the optimal designs and manufacturing technologies of various types of porous cellular metal and mechanical behaviors of a thermally grown oxide at high temperature.