Finite Element Analysis on Welding-Induced Distortion of Automotive Rear Chassis Component

Welding-induced distortion is a major concern for the industrial joining practice. The welding-induced distortion at the weldment between the coupled torsion beam axle (CTBA) of the automotive rear chassis parts and trailing arm connected to the wheel hub axle module seriously affects the tow angle, camber angle, and caster of the wheel axle. In this paper, the welding process between CTBA and trailing arm was numerically analyzed via SYSWELD (i.e., a finite element analysis code), using the material properties predicted via J-MatPro SW, material properties software, considering the thermo-mechanical-metallurgical properties of materials. From the numerical study for the weldment of CTBA and trailing arm, we predicted the welding and thermal distortions, temperature variation, microstructure, and residual stress at the concerned area. As a result, the temperature of the welded area was predicted between 102 degrees C and 840 degrees C at the end of weldment and converged to room temperature after 1000 s. The maximum portion of the martensite structure at the welded area was expected to be 55%. The expected distortions of the trailing arm after the weldment were 0.52 mm, -1.47 mm, and 0.44 mm in the x, y, and z-directions, respectively. Finally, the limitations of this research and recommendations are presented.