Residual stress evolution regularity in thermal barrier coatings under thermal shock loading

• Main Authors: Ximin Chen, Zhanwei Liu, Yang Yang
• Format: Article
• Language: English
• Published: Elsevier 2014-01-01
• Series: Theoretical and Applied Mechanics Letters
• Subjects: thermal barrier coating; residual stress; DIC; hole-drilling method; micro-Raman spectroscopy
• Online Access: http://www.sciencedirect.com/science/article/pii/S2095034915303044

Residual stress evolution regularity in thermal barrier ceramic coatings (TBCs) under different cycles of thermal shock loading of 1100°C was investigated by the microscopic digital image correlation (DIC) and micro-Raman spectroscopy, respectively. The obtained results showed that, as the cycle number of the thermal shock loading increases, the evolution of the residual stress undergoes three distinct stages: a sharp increase, a gradual change, and a reduction. The extension stress near the TBC surface is fast transformed to compressive one through just one thermal cycle. After different thermal shock cycles with peak temperature of 1100°C, phase transformation in TBC does not happen, whereas the generation, development, evolution of the thermally grown oxide (TGO) layer and micro-cracks are the main reasons causing the evolution regularity of the residual stress.