Effect of Multiple Impacts on Thin Leading Edges of Turbine Blade Treated by Laser Shock Peening Process

In this paper, we will study the influence of multiple laser impacts on thin leading edges of a turbine blade. A numerical analysis based on a 3D finite element method of thin leading edge specimens of a turbine blade made of titanium super-alloy (Ti–6Al–4V) is performed using the commercial software ABAQUS. A repetitive time Gaussian increment pressure that is uniformly applied at a square affected region is used to characterize the LSP loading. We apply the visco-elastic-plastic of the Johnson-Cook law coupled with damage in order to develop the treated material behavior law. The objective of this simulation is to predict the mechanical surface modifications generated by the laser shock processing: (i) the residual stresses, (ii) the plastic strains and (iii) the Johnson-Cook superficial damage. These modifications are well analyzed for thin leading edges of a turbine blade treated by a square laser spot that can effectively treat a considerable part with a coverage rate that is below 5% comparing with a circular laser spot.