DP980高强钢激光焊接组织与性能研究

Study of Fiber Laser Welding for DP980 High Strength Steel

采用IPG YLR-6000-ST2光纤激光器对DP980高强钢板进行焊接试验,主要研究了工艺参数对焊接质量的影响,分析了焊缝的显微组织与力学性能。结果表明DP980高强钢板光纤激光焊接接头成形良好;焊缝组织呈柱状晶结构,主要为侧板条铁素体,针状下贝氏体及少量板条马氏体;热影响区宽度很窄,晶粒长大不明显;显微硬度由焊缝中心向母材逐渐降低,没有出现软化现象。

Welding experiments of DP980 high strength steel plate produced by Baosteel with IPG YLR-6000-ST2 fiber laser have been processed. The influence of welding parameters on welding quality has been investigated. Microstructure and mechanical character of welding seam have also been analyzed. It shows that the joint appearance of DP980 high strength steel welded with fiber laser has good performance and the mechanics property is good without fit-up gap. The microstructure of weld bead is columnar crystals; Heat-affected zone is narrow and the grain grows with little size; the measured micro-hardness values of the sample decrease smoothly from weld center to base metal.