Temperature dependence of the deformation behavior and the residual stress in 304 stainless steel beams with single-sided Al₂O₃ coatings of varying thicknesses are analyzed using the image relative method. The results demonstrate that, due to the mismatch of thermal expansion coefficient between the coating and substrate, residual stresses were produced, which caused the bending deformation of the single-side coated specimens. Moreover, coating thickness significantly influences the deformation behavior of specimens. Within the elastic deformation regime, the single-side coated specimens would exhibit alternating bending and flattening deformations in response to the fluctuations of temperature. The higher ratio of the coating thickness to the substrate thickness is, the smaller bending curvature of specimens becomes, and the lower residual compressive stresses in the coating are. For the specimens undergoing elastic deformation, residual stresses can be effectively calculated through the Stoney’s formula. However, as the thickness of coating is close to that of substrate (the corresponding specimens would be regarded as the laminated composites), plastic deformation occurs. And the residual stresses in those specimens vary along the direction of the thickness and the length. In addition, the residual stress decreased with increasing temperature because of the stress relaxation.

In this work, the influences of substrate characteristics on the deformation and residual stress in ZrO₂ coatings deposited on one side carbon steel, 316 stainless steel and 304 stainless steel are analysed via the image relative method. Based on the changes in bending deflection at different temperatures, temperature dependence of the residual stresses in the above three specimens was achieved through Stoney’s formula. Results show that a compressive residual stress is generated during the cooling process because the ZrO₂ coating has a lower coefficient of thermal expansion (CTE) than that of the substrates. Additionally, by comparing the images of specimens under different temperatures, it can be found that the difference in CTE (∆α) between coating and substrate, as well as the temperature difference (∆T) between zero-stress temperature and testing temperature, determine the residual stresses in the coated specimens. And the higher the ∆α and ∆T, the higher the residual compressive stress and bending deflection. Moreover, temperature dependence of the residual stress could also be found through the image relative method.