Numerical Simulation and Fatigue Properties of Laser Spot Weld-Bonding DP590 Dual-Phase Steel Joints

抄録

In this paper, cold-rolled DP590 dual-phase steel sheets with 1.5 mm thickness were weld-bonded by a fiber laser. In order to study the tensile shear strength of laser spot-welding and laser weld-bonding joints, the orthogonal test was designed with three parameters: welding power, welding time and off-focus value. The tensile shear test and the fatigue test were carried out. The vaporization of the adhesive and its disruption to the molten pool during the weld-bonding process were simulated. The results show that the tensile and fatigue strength of the laser weld-bonding joints are higher than the laser spot-welding joints. Simulation results demonstrate that the perforation is caused by the gas produced by the gasified adhesive being discharged from the center of the molten pool under high pressure.

Fig. 5 Material status with a viscoelastic attenuation coefficient of 100/s. (a) 0.1 ms; (b) 0.2 ms; (c) 0.4 ms; (d) 0.6 ms; (e) 0.8 ms; (f) 1 ms.