基于氮气保护的316L不锈钢大功率激光焊接工艺研究  

Study on High-Power Laser Welding Process of 316LS tainless Steel with Nitrogen Shield

作　　者：雷小伟 陈利阳 张毅 马照伟 LEI Xiaowei;CHEN Liyang;ZHANG Yi;MA Zhaowei(Luoyang Ship Material Research Institute,Luoyang 471023,China)

机构地区：[1]中国船舶集团有限公司第七二五研究所,河南洛阳471023

出　　处：《材料开发与应用》2023年第3期24-30,共7页Development and Application of Materials

基　　金：郑洛新自创区产业集群专项(201200211400)。

摘　　要：针对316L不锈钢大功率激光焊接气孔问题,利用大功率光纤激光焊接设备,对10 mm厚316L奥氏体不锈钢进行激光焊接试验,发现采用氮气作为侧吹保护气体时,相比纯氩保护气,焊缝气孔率明显下降,焊缝截面更窄。采用氮气作为侧吹实现了成型美观的“小孔型”激光深熔焊接,焊缝正面宽度约2 mm,焊缝背面宽度约1.5 mm,焊缝正面有轻微下凹,深宽比达5∶1。对焊接试板进行了射线检测和渗透检测,均满足NB/T 47013—2015的Ⅰ级标准;对焊接接头按照NB/T 47014—2011进行了力学、工艺性能测试,测试结果均满足标准要求;冲击性能测试显示焊缝冲击性能优良,韧窝明显,为典型的韧性断裂。微观金相显示焊缝区主要为树枝状奥氏体+析出相,热影响区主要为孪晶奥氏体+少量δ铁素体。The laser welding test of 10 mm thick 316L austenitic stainless steel with nitrogen shield was carried out by high-power fiber laser in order to reduce pores.It is found that the porosity decreases significantly with nitrogen as shield gas than ar⁃gon as shield gas,and that the weld section is narrower.The excellent“keyhole”welding joint is obtained.The width of the weld surface is about 2 mm;the width of the weld root about 1.5 mm.The weld face is slightly concave,and the depth-width ration is 5∶1.The results of RT and PT meet the requirements of NB/T 47013—2015 GradeⅠ.The results of mechanical and technological properties meet the requirements of NB/T 47014—2011.The impact performance test shows that the weld has ex⁃cellent impact performance.The impact fracture is observed by microscopy,and the dimples are obvious,which is a typical duc⁃tile fracture.The weld zone is mainly dendritic austenite and precipitated phase,and the HAZ is mainly twinning austenite and δ-ferrite.

关 键 词：316L不锈钢 大功率激光焊 氮气保护 接头性能 

分 类 号：TG44[金属学及工艺—焊接]