焊后热处理对6061-T6铝合金激光-MIG复合焊接头力学性能及组织的影响  

Effect of Postweld Heat Treatment on Mechanical Properties and Microstructure of 6061-T6 Aluminium Alloy Laser-MIG Composite Welded Joint

作　　者：金鑫 祝哮 唐鸿洋 田春雨 刘东利 JIN Xin;ZHU Xiao;TANG HongYang;TIAN Chunyu;LIU Dongli(Liaoning Zhongwang Group Co.,Ltd.,Liaoyang 111000,China)

机构地区：[1]辽宁忠旺集团有限公司,辽宁辽阳111000

出　　处：《铝加工》2024年第6期64-68,共5页Aluminium Fabrication

基　　金：国家重点研发计划项目(2021YFB3704205)。

摘　　要：以采用激光-MIG复合焊的船舶用6061-T6铝合金为主要研究对象,通过对焊后试样进行单级时效及固溶+时效两种热处理制度,分析焊后热处理对焊缝内部金相显微组织及力学性能的影响。研究结果表明:在复合焊后进行热处理并未对焊缝区组织产生明显影响,只是晶粒组织得到了不同程度的细化;单级时效制度下接头硬度提高了15.7 HV,固溶+时效热处理制度下接头硬度提高18.6 HV;单级时效制度下接头拉伸强度相比于未热处理提升18 MPa,固溶+时效制度下接头拉伸强度相比于未热处理提升30 MPa;在单级时效及固溶+时效后,接头处的韧窝变浅,塑性降低,强度有所提高,并且经固溶+时效后接头断裂位置由HAZ(热影响区)转至焊缝处。The effect of postweld heat treatment on the internal microstructure and mechanical properties of the welded 6061-T6 aluminium alloy with laser-MIG composite welding was analyzed by single stage ageing and solution+ageing heat treatment on the welded samples.The results show that postweld heat treatment has no obvious effect on the microstructure of the weld zone,but the grains are refined to different degrees.The hardness of the single stage ageing joint is increased by 15.7 HV,and the hardness of the joint under solution+ageing heat treatment system is increased by 18.6 HV.Compared with the joint without postweld heat treatment,the tensile strength of the joint under single stage ageing system is increased by 18 MPa,and the tensile strength under solution+ageing system is increased by 30 MPa.After single stage ageing and solution+ageing,the dimple at the joint becomes shallow,the plasticity decreases,the strength increases,and the fracture position of the joint changes from the HAZ to the weld after solution+ageing.

关 键 词：焊后热处理 6061-T6铝合金 激光-MIG复合焊 微观组织 力学性能 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG166.3[金属学及工艺—金属材料] TG407[金属学及工艺—金属学]