Microstructure and mechanical properties of high-energy shot-peened Mg/Ti weldments

In the present work, high-energy shot-peening treatment was applied to the tungsten inert gas welded-brazed Mg/Ti weldments. The surface characteristics, residual stress distribution, microstructures and mechanical properties of HESP-treated Mg/Ti weldments were investigated. Results revealed that with the optimised peening time of 60s and the peening pressure of 0.15MPa, the elimination of surface voids and cracks, high compressive residual stress and surface strain strengthening of joint were introduced in the HESP-treated Mg/Ti weldments. The average tensile strength increased 24.5% to 241 MPa over the joints without HESP treatment (193.5 MPa) and fracture even occurred in the Mg alloy base metal.