关键词: 白车身；焊接顺序；焊接变形；有限元仿真；CAE 分析

Abstract: To study the effect of spot weld sequence on structural geometrical variation of body in white, fixtures of U-section joint and double-direction weld lap joint with adjustable assembly gap was designed. With the weld spot modeled by node-coupling method, the welding finite element model was established with Abaqus software. The weld process was established with clamping and welding step and spring-back step, and the structural geometrical variation under different welding sequences was analyzed. Compared with experimental results, the simulation model was proved to be robust, and be applied to the optimization of welding sequence of chain mounting surface and floor positioning hole structure of body in white. The results show that mechanical force and elastic strain are the main causes of weld-induced geometry variation. The built of finite element model supplied reliable way and basis for the optimization of body structure weld sequence.

Key words: Body in white; Weld sequence; Weld distortion; Finite element simulation; CAE analysis