The variations of microstructures and hardness of titanium matrix composite (TiBÂ +Â TiC)/Ti-6Al-4V after shot peening

After shot peening (SP), the variations of microstructures and hardness of (TiB + TiC)/Ti-6Al-4V were investigated. The microstructures of the surface and cross-section were studied, and the results revealed that the convex and concave features appeared on the surface after SP. Based on the microstructures of cross-section, the micrograph showed the random inclination of reinforcements in the surface layer, which illuminated that the reinforcements were yielded to the random deformation of matrix during SP. The variations of hardness before and after SP were investigated via the nano-indentation method. The results indicated that the variations of hardness were caused by the different extent of deformation under surface. All results were discussed in detail.