电焊机2026，Vol.56Issue(8)：68-79,12.DOI:10.7512/j.issn.1001-2303.2026.08.07
FB780双相钢激光-电弧复合焊焊缝成形与背部驼峰抑制机理研究
Weld Formation and Backside Humping Suppression Mechanism in Laser-Arc Hybrid Welding of FB780 Ferrite-Bainite Dual-Phase Steel
摘要
Abstract
Formation instabilities,including backside humping,collapse and porosity,often occur during laser-arc hybrid welding of 4 mm thick FB780 ferrite-bainite dual-phase steel.In this study,a fiber laser-arc hybrid welding process was used to investigate the effects of heat-source leading mode,laser power,welding current and welding speed on weld forma-tion,with high-speed imaging used to analyze arc morphology,droplet transfer and backside formation.The results show that the arc-leading mode produces more stable front and backside weld formation than the laser-leading mode by preheating the base metal,improving laser absorption and stabilizing arc-keyhole coupling.Under arc-leading conditions,a laser power of 5.0 kW,welding current of 120 A and welding speed of 1.8 m/min provide the best balance among heat input,keyhole sta-bility and solidification.Increasing laser power from 4.0 kW to 5.0 kW eliminates backside humping by changing the key-hole from critical to stable penetration,whereas excessive power causes root sagging and collapse.Backside humping is mainly caused by periodic switching between partial and full penetration,which breaks the force balance of the root liquid bridge.Compared with solid wire,flux-cored wire shows a wider process window and better backside formation stability.The findings reveal the intrinsic link between sustained keyhole penetration and humping suppression,offering a practical basis for process window design in hybrid welding of FB780 high-strength steel.关键词
FB780双相钢/激光-电弧复合焊/背部驼峰/焊缝成形/高速摄像分类
矿业与冶金引用本文复制引用
张海龙,方乃文,赵梓森,信国松,王新洪,牛董山钰,常朝祥,邹勇..FB780双相钢激光-电弧复合焊焊缝成形与背部驼峰抑制机理研究[J].电焊机,2026,56(8):68-79,12.基金项目
泰山产业领军人才工程(2024001) （2024001）
