Numerical simulation and welding parameters optimization for minimum deformation of AHSS based on RSM & QGA

Dual-phase (DP) steel is a kind of advanced high strength steel (AHSS) and is widely used in the automobile industry. However, the method of optimizing welding parameters through practical production is time-consuming and the optimal solution would be ignored easily. The temperature field, residual stress field and deformation of DP780 during welding process are studied by numerical simulation. Results show that the double ellipsoid heat source model selected in this study is consistent with the actual production. The temperature field around the welding line is elliptical. At the same time, the residual stress and deformation on the surface of the component are symmetric about the welding line. The residual stress at the start point of welding line is the largest, and the largest residual stress is about 500 MPa. At the same time, the largest deformation appears in the welding line, and the largest deformation is 0.85 mm. Additionally, a new method of parameter optimization based on response surface method (RSM) & quantum genetic algorithm (QGA) is proposed to reduce the deformation effectively. The verification also shows the effectiveness of the method with an error of 1.37%.