激光功率对异种钢激光焊接接头组织与性能的影响  

Effect of Laser Power on Microstructure and Properties of Dissimilar Steel’s Laser Welded Joint

作　　者：刘海 陈辉[1] Liu Hai;Chen Hui(School of Materials Science and Engineering,Southwest Jiaotong University,Chengdu,Sichuan 610031,China;Department of Mechanical Engineering,Sichuan College of Chemical Technology,Luzhou,Sichuan 646005,China)

机构地区：[1]西南交通大学材料科学与工程学院,四川成都610031 [2]四川化工职业技术学院机械工程学院,四川泸州646005

出　　处：《激光与光电子学进展》2021年第23期192-200,共9页Laser & Optoelectronics Progress

基　　金：国家重点研发计划项目(2016YFB1102100)。

摘　　要：采用单激光技术对5㎜厚的Q345B低合金钢和304不锈钢进行焊接。通过调整激光功率,对不同工艺参数下异种钢焊接接头的焊缝宏观形貌、金相组织、显微硬度及抗拉强度进行分析。结果表明:当激光功率小于4 kW时焊缝不能完全焊透,大于7 kW时焊缝又会焊穿塌陷;在激光功率由4 kW增加到7 kW的过程中,焊缝组织均为典型的板条状马氏体,激光功率为6 kW时焊缝中心的硬度最大,且焊缝的气孔数量最少;试样拉伸断裂位置均在Q345B母材上,没有在焊缝上断裂;焊缝中主要包含γ-Fe、α-Fe、Cr_(2)Ni_(3)、Fe_(2)Ni_(3)等相,没有出现大量M_(23)C_(6)和σ相等有害相。The single laser technology was used to weld 5-mm thick Q345B low-alloy steel and 304 stainless steel.By modifying laser power,the microstructure,microhardness,and tensile strength of welded joints made of dissimilar steel were analyzed under various process parameters.The results showed that the weld could not penetrate entirely when the laser power was less than 4 kW and the weld would collapse when the laser power was greater than 7 kW.The weld microstructure was typical strip martensite when the laser power was increased from4 kW to 7 kW;the weld center hardness was maximum and the weld porosity was the lowest at 6 kW.The samples’tensile fracture sites were all present on the Q345B base material with no weld fracture.γ-Fe,α-Fe,Cr_(2)Ni_(3),and Fe_(2)Ni_(3) phases dominate in welds,with little M_(23)C_(6),σphase,and other hazardous phases.

关 键 词：激光光学 激光功率 异种钢 显微组织 力学性能 

分 类 号：TG456.7[金属学及工艺—焊接]