Investigations on the residual stress and mechanical properties of DH36 steel repaired by laser shock forging assisted arc repair method

Abstract

The laser shock forging assisted arc repair (LSF-AR) technology is newly developed. To validate the effectiveness of this technology, the residual stress and mechanical properties of DH36 steel repaired by arc repair (AR) and LSF-AR were comparatively investigated through numerical simulation and experiment. The simulated deformation values of the repaired sample were first compared with the experimental measured data to confirm the validity of the simulation settings. Afterwards, a comparative analysis was conducted on the residual stress distributions acquired from both numerical simulations and experimental measurements, which were found in good agreement. The results indicated that the AR sample exhibited significant tensile residual stress (TRS) in the weld seam, but LSF-AR notably reduced this TRS, with the TRS at the weld seam center decreasing from 395.4 MPa to 204.3 MPa. Compared to the AR sample, the LSF-AR sample showed improved tensile strength and elongation. This study validated the feasibility of applying LSF method during AR processes to achieve low residual stress and high-performance repair.