离焦量对05Cr17Ni4Cu4Nb/HR-2异种钢焊接接头组织和性能的影响  

Effect of Defocusing Amount on Microstructure and Properties of Laser Welded 05Cr17Ni4Cu4Nb/HR-2 Dissimilar Steel

作　　者：王群 刘航天 韩柯 雷华东[1] 赵健[2] Wang Qun;Liu Hangtian;Han Ke;Lei Huadong;Zhao Jian(Institute of Machinery Manufacturing Technology,China Academy of Engineering Physics,Mianyang 621900,Sichuan,China;School of Materials Science and Engineering,Shanghai University of Engineering Science,Shanghai 201620,China;School of Materials Science and Engineering,Jiangsu University,Zhenjiang 212013,Jiangsu,China)

机构地区：[1]中国工程物理研究院机械制造工艺研究所,四川绵阳621900 [2]上海工程技术大学材料科学与工程学院,上海201620 [3]江苏大学材料科学与工程学院,江苏镇江212013

出　　处：《应用激光》2024年第12期63-71,共9页Applied Laser

基　　金：上海市Ⅲ类高峰学科—材料科学与工程(高能束智能加工与绿色制造)。

摘　　要：通过改变离焦量对20 mm厚05Cr17Ni4Cu4Nb/HR-2异种不锈钢进行激光深熔焊接工艺试验,采用光学显微镜、扫描电镜及能谱仪对焊接接头微观组织进行表征,并利用显微硬度仪、电子万能材料试验机及金属摆锤冲击试验机对接头力学性能进行测试。试验结果表明,焊接工艺参数不同时,焊缝成形良好,未产生焊接缺陷。焊缝微观组织均为δ铁素体+奥氏体,但离焦量的改变对δ铁素体形态和数量产生了显著影响。随着离焦量的增大,焊缝区晶粒逐渐细化,提高了焊缝区的显微硬度,焊缝区显微硬度均高于HR-2母材。三点弯曲测试时,弯曲位置均出现在HR-2母材侧,表明焊接接头具有较好的弯曲强度。当离焦量为10 mm时,焊缝区蠕虫状δ铁素体的形成提高了焊缝韧性,接头冲击吸收功达到177.9 kJ,因而接头冲击韧性最优。The laser deep fusion welding test of 20mm thick 05Cr17Ni4Cu4Nb/HR-2 dissimilar stainless steel was carried out by using different defocus,and the microstructure of the welded joint was analyzed by optical microscope,scanning electron microscope and energy spectrum.The mechanical properties of welded joints were studied by microhardness tester,electronic universal material tester and metal pendulum impact tester.The test results show that the weld is well formed and no welding defects occur under different technological parameters.The microstructures of weld seams are all ferrite+austenite,but the morphology and quantity of ferrite change.With the increase of defocusing amount,the grain in weld zone is gradually refined,and the microhardness of weld zone is improved,which is higher than that of HR-2 base metal.In the three-point bending test,the bending positions all appear on the HR-2 base metal side,indicating that the welded joint has good plasticity.When defocusing is 1omm,vermicular ferrite in weld zone improves weld toughness and the impact toughness reaches the maximum.

关 键 词：离焦量 异种钢激光焊 微观组织 力学性能 

分 类 号：TG456[金属学及工艺—焊接]