Microstructures and Mechanical Properties of disk laser Butt Welded galvanized steel sheets
T. Jiang, K. Wang, D. Xia, Z-L. Huang, M-X. Liu, W. Fan and Y. Zeng
The microstructure and mechanical properties in disc laser butt welding of two galvanized steel sheets with different thickness were examined in this work. The results of the investigation demonstrate that a highly formable weld line is available through the laser welding. Microstructures in both base metals are mainly pearlite and ferrite, and the fusion zone is consist of lath-shaped martensite and ferrite. Deep drawing formability of the butt-welded plate in transverse direction is larger than that in the longitudinal direction. The yield strength and the tensile strength of the weld bead exceed those of the base metal, and the microhardness of both the weld bead and the heat affect zone (HAZ) is higher than that of the base metal.
Keywords: Disk laser, galvanized steel sheet, HSLA340+Z, HC340LAD+Z, laser welding, microstructure, mechanical properties, automobile