Thermal barrier systems are susceptible to instability of the thermally grown oxide (TGO) at the interface between the bond coat and the thermal barrier coating (TBC). The instabilities have been linked to thermal cycling and initial geometrical imperfections, as well as to misfit strains due to both oxide growth and thermal expansion misfit. Numerical simulations are used to investigate the role of the thermo-mechanical properties of the TBC in this instability. It is found that the TBC constrains the deformation, whereupon instabilities develop preferentially in regions where crack-like imperfections either pre-exist in the TBC or are created because of the induced stresses.
Karlsson, A., Xu, T., and Evans, A., 2002, "The Effect of the Thermal Barrier Coating on the Displacement Instability in Thermal Barrier Systems," Acta Materialia, 50(5) pp. 1211-1218.
NOTICE: this is the author’s version of a work that was accepted for publication in Acta Materialia. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Acta Materialia, 50, 5, March 14, 2002; 10.1016/S1359-6454(01)00422-0