Deformation measurement and simulation of Ti–6Al–4V blades induced by shot peening process

One factor that plays an important role in the aerodynamic performance of aeroengines is the shape of the blades, which is vulnerable to change resulting from the plastic deformation and the residual stresses induced by the complex manufacturing processes, especially the shot peening. However, few studies were focused on the detailed strategies of shot peening on the complex profile and the superposition effects of residual stresses during the entire manufacturing processes. In this paper, based on the concept of eigenstrains, we investigated the effect of shot peening on residual stresses and deformation of the blade by combining the experimental measurement and the local-global simulation. The results show that the initial residual stresses induced by the previous milling process could be neglected. After the shot peening, the blade has the largest deformation if considering the initial residual stresses during milling with large amount of material removal, compared with the case without considering initial residual stresses and the case considering initial residual stresses after dynamic milling of blades. Furthermore, the in-out sequence of shot peening results in the smallest deformation and the pre-deformation of the blade can effectively offset this deformation. Finally, the shot peening intensity should not be too high in practical blade manufacturing for small thickness in order to avoid compromising the reliability and safety of blades.