双光束激光焊接304不锈钢中光斑间距对小孔行为影响  

Effect of Spot Spacing on Keyhole Behavior in Dual-Beam Laser Welding of 304 Stainless Steel

作　　者：陈凯源 聂璞林[1] 魏祺 黄坚[1] 姚成武[1] Chen Kaiyuan;Nie Pulin;Wei Qi;Huang Jian;Yao Chengwu(Shanghai Key Laboratory of Materials Laser Processing and Modification,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]上海交通大学上海市激光制造与材料改性重点实验室,上海200240

出　　处：《激光与光电子学进展》2024年第23期263-271,共9页Laser & Optoelectronics Progress

摘　　要：在激光深熔焊过程中,小孔行为的不稳定是造成焊缝中各种缺陷的重要原因之一。以304不锈钢作为焊接材料,通过高速摄影研究了能量比例为50∶50的串行双光束条件下不同光斑间距对小孔行为的影响。通过焊接过程中对小孔形态的观察和气孔情况分析,研究了双光束对小孔稳定性提升机理。结果表明:随着光斑间距从0 mm增大至1.800 mm,焊接熔池的小孔会由单个小孔向两个独立小孔过渡,小孔的稳定性会先增大后减小;当间距为0.450 mm时,小孔深度变化的标准差仅为0.03,可获得最稳定的小孔。小孔稳定性提升的原因主要是在合适的光斑间距下小孔内金属液体的不均匀蒸发明显减少,并且小孔前后壁距离得到了有效拓宽。Keyhole instability is an important factor influencing defect formation in deep-penetration laser welding.This study investigates the use of 304 stainless steel as the welding material and examines the influence of spot spacing on keyhole behavior during dual-beam laser welding with a 50∶50 energy ratio.A high-speed camera was used for this intensive investigation.This study explores how a dual-beam laser source enhances keyhole stability by analyzing keyhole morphology and porosity.Results indicate that as the spot spacing increases from 0 to 1.800 mm,a single keyhole splits into two,with keyhole stability initially increasing and then decreasing.The most stable keyhole is achieved at a spot spacing of 0.450 mm,as indicated by a standard deviation in keyhole depth variation of 0.03.This improvement is mainly due to a noticeable reduction in the nonuniform evaporation of the metal liquid and an increase in the distance between the keyhole front and back walls.

关 键 词：激光焊接 串行双光束 小孔行为 304不锈钢 

分 类 号：TG456.7[金属学及工艺—焊接]