Residual stress redistribution within high-temperature coatings due to surface cracks

Residual stress is one of the important mechanical properties of high-temperature coatings and it will be redistributed if the physical discontinuities are presented. The objective of this theoretic study was to investigate the residual stress redistribution within a high-temperature ZrO2/NiCoCrAlY coating due to the presence of surface crack. Results indicated that the shape and dimension of crack had significant influences on the magnitude and distribution of the residual stresses within coatings. When the surface crack was absent, there was a remarkable stress concentration near the edge of the coating. However, the location of the stress concentration may be changed due to the presence of surface crack. The effect of multi-surface crack on the residual stress redistribution within the coating was also discussed.