Effect of shot peening on microstructure, nanocrystallization and microhardness of Ti–10V–2Fe–3Al alloy surface

Severe plastic deformation of Ti–10V–2Fe–3Al alloy in the surface region was caused by shot peening at air pressure of 0.6 MPa with processing time ranging from 1 to 45 min. The results showed that the thickness of surface deformation layer was proportional to the processing time, the microhardness of the shot-peened surface increased from 280 to 385 HV, and the depth of highly hardening layers arrived at 200 μm. It was worth noting that a grain size gradient from nanocrystalline on the surface toward coarse grain in the matrix was obtained during the shot peening process and the minimum grain size in the top surface after shot peening was about 100–200 nm.