Effect of shot peening on surface characteristics of ni-based single-crystal superalloy

Abstract

The effect of shot peening on surface characteristics of DD3 Ni-based single-crystal superalloy including microstructures, texture and residual stress were investigated, utilizing XRD analysis. Results showed that the polycrystals was introduced into the surface of single-crystal specimen by shot peeing and the initial texture (200) was erased after 60 s-processing. The variation in microstructure was mainly influenced by the processing time and finer domains as well higher microstrain were obtained after 60 s-processing. The value of residual stress depended upon processing time and measurement direction. In the early period of processing (10 s), residual stress was anisotropy, being significant smaller in h110i direction. With the processing time increased, the anisotropic residual stress gradually changed to isotropic residual stress, due to domainorientation randomization, domain refinement and increase in plastic strain. Also increasing processing time could significantly enhance the magnitude of residual stress and the microhardness. In addition, the influence of processing time on work hardening and residual stress was discussed, based on the deformation mechanism. ©2013 The Japan Society for Technology of Plasticity.