2 000 MPa级热成形钢双光斑激光 焊接接头成形研究  

Double Spot Laser Welded Joint Forming of 2000 MPa Grade Hot Stamping Steel

作　　者：张文广 刘岩[2] 杜安娜 杨栈琳 李博 ZHANG Wen-guang;LIU Yan;DU An-na;YANG Zhan-lin;LI Bo(School of Mechanical Engineering,Shenyang University,Shenyang 110044,China;Liaoning Provincial Key Laboratory of Advanced Materials&Preparation Technology,Shenyang University,Shenyang 110044,China)

机构地区：[1]沈阳大学机械工程学院,沈阳110044 [2]沈阳大学辽宁省先进材料制备技术重点实验室,沈阳110044

出　　处：《精密成形工程》2023年第12期142-149,共8页Journal of Netshape Forming Engineering

基　　金：辽宁省自然科学基金(2023-MS-320);辽宁省重点研发计划(2020JH2/10100011)。

摘　　要：目的探究焊接参数对PHS2000型热成形钢焊接接头宏观形貌的影响,利用双光斑激光焊接工艺减少焊接缺陷,得到形貌良好的焊接接头。方法使用德国通快公司的TruDisk 5000型双光斑激光器对2000 MPa级热成形钢进行激光焊接。使用金相显微镜对不同参数下焊接接头正面和背面的宏观形貌及焊缝横截面的熔深和熔宽进行研究。结果随着激光功率从3500 W增大到4400 W,焊接接头成形良好,熔深大体呈增大趋势,深宽比先下降后上升再下降;随着焊接速度从50 mm/min增大到250 mm/min,熔深、熔宽基本降低,深宽比总体呈下降趋势;随着芯环比的提高,焊缝背面成形变差,熔深在芯环比为55%~65%时较理想,深宽比总体呈W形上升;当离焦量为0 mm时,焊缝背部出现了较为严重的烧损变色,并且在焊缝两侧产生了飞溅。而随着离焦量降低到−4 mm,烧损变色情况得到改善。结论激光功率和芯环比对焊接接头成形的影响较为显著。得到了成形良好的焊接接头,且在激光功率为4700 W、焊接速度为150 mm/min、芯环比为65%、离焦量为−2 mm的焊接参数下,1.4 mm厚2000 MPa级热成形钢双光斑激光焊接接头的成形效果最佳。The work aims to investigate the effect of welding parameters on the macroscopic morphology of welded joints of PHS2000 hot stamping steel,to reduce welding defects with the double spot laser welding process and obtain welded joints with good morphology of PHS2000 hot stamping steel.The Trudisk 5000 dual spot laser from TRUMPF,Germany,was selected for laser welding of 2000 MPa grade hot stamping steel.The front and back morphology and the cross-sectional welding penetration and depth of welded joints under different parameters were studied and analyzed with a metallurgical microscopy.Experimental results showed that as the laser power from 3500 W to 4400 W,the welded joint was well formed,the penetration increased generally,the penetration to width ratio decreased generally.As the welding speed increased from 50 mm/min to 250 mm/min,the weld penetration and weld width basically decreased,the penetration-to-width ratio showed a decreasing trend in general.As the core raised,the formation of the back of the weld was deteriorated,and the penetration was ideal when the core was set to 55%-65%.The overall penetration-width ratio was in an ascending"W"shape.When the defocus amount was set to 0 mm,severe burn discoloration on the back of the weld and spatter on both sides of the weld were observed.However,as the defocus amount decreased to−4 mm,the burn damage was improved.In summary,this experiment reveals that the laser power and the core have significant influence on the formation of welded joints.The best forming effect of welded joint of 1.4 mm thick 2000 MPa grade hot stamping steel are obtained with the dual spot laser welding technique when the laser power is 4700 W,welding speed is 150 mm/min,core is 65%,and defocus amount is−2 mm.

关 键 词：PHS2000型热成形钢 双光斑激光器 激光焊接 宏观形貌 显微组织 

分 类 号：TG456.7[金属学及工艺—焊接]