Abstract
The surface strain of thermal sprayed coating and substrate were measured with ESPI method and the delamination behavior of sprayed coating investigated by comparing the surface strain of both materials. Then it was examined that the generation of delamination was defined. As the results, both surface strain was corresponding until some stresses when thermal sprayed coating and substrate were added static load. But surface strain of thermal sprayed coating was decreased while some cracks and delaminations occurred on coating or coating/substrate, and the value of strain has become considerably small than surface strain of substrate. Therefore, it is thought the delamination of coating can be defined according to critical strain due to the surface strain of both materials. Moreover, it may be effective as the evaluation method that the quality of the coating was evaluated by using critical strain of delamination obtained by ESPI method.
