航空学报 > 2022, Vol. 43 Issue (2): 625880-625880   doi: 10.7527/S1000-6893.2021.25880

6061-T6铝合金激光诱导电弧焊轧复合成形组织性能

宋刚1,2, 刘振夫1,2, 程继文1,2, 刘黎明1,2   

  1. 1. 大连理工大学 材料科学与工程学院, 大连 116024;
    2. 大连理工大学 辽宁省先进焊接技术重点实验室, 大连 116024
  • 收稿日期:2021-05-31 修回日期:2021-06-11 发布日期:2021-09-06
  • 通讯作者: 宋刚 E-mail:songgang@dlut.edu.cn
  • 基金资助:
    国家自然科学基金(U1764251,U1960111);中央高校基本科研业务费专项资金(DUT21LAB133)

Microstructure and properties of welding-rolling composite forming for 6061-T6 aluminum alloy by laser induced arc welding

SONG Gang1,2, LIU Zhenfu1,2, CHENG Jiwen1,2, LIU Liming1,2   

  1. 1. School of Material Science and Engineering, Dalian University of Technology, Dalian 116024, China;
    2. Liaoning Advanced Welding Technology Key Laboratory, Dalian University of Technology, Dalian 116024, China
  • Received:2021-05-31 Revised:2021-06-11 Published:2021-09-06
  • Supported by:
    National Natural Science Foundation of China (U1764251, U1960111); The Fundamental Research Funds for the Central Universities (DUT21LAB133)

摘要: 针对6061-T6热处理强化铝合金焊后由"接头软化"导致的力学性能严重下降等问题,提出激光诱导电弧填丝焊及焊后局部轧制复合成形工艺,利用焊接接头余高的局部变形辅助强化接头"过时效软化区"。结果表明通过焊轧复合成形方法能得到成形良好且无缺陷的接头。与焊接接头相比,焊轧复合成形接头硬度整体更加均匀,软化最严重位置的硬度由71.2 HV提升到87.8 HV,提升了23.3%;焊轧复合成形接头的平均抗拉强度由246 MPa提升到284 MPa,相对提升了15.4%,达到母材的91.6%。轧制工艺使焊接接头发生局部强制变形,焊缝区等轴晶晶粒被压实且焊缝变宽。焊缝金属向两侧挤压使热影响区组织发生协同变形,导致位错密度增加,实现"过时效软化区"强化效果。

关键词: 铝合金, 接头软化, 激光诱导电弧, 焊轧复合成形, 局部变形

Abstract: Aiming at the problem that the mechanical properties of 6061-T6 heat-treat aluminum alloy are seriously decreased after welding due to "joint softening", the laser-induced arc filler wire welding and post-weld partial rolling composite forming process is proposed. The partially forced deformation of the residual height of welded joints is used to assist in strengthening the "over-aged softening zone" of the joint. The results show that the welding-rolling composite forming method can obtain well-formed and defect-free joints. Compared with welded joints, the hardness of welding-rolling composite forming joints is more uniform as a whole, and the hardness value of the most seriously softened position is increased from 71.2 HV to 87.8 HV, which is increased by 23.3%; the average tensile strength of welding-rolling composite forming joints is also increased from 246 MPa to 284 MPa, a relative increase of 15.4%, reaching up to 91.6% of the base metal. The rolling process causes partially forced deformation of the welded joint, and the dendrite crystals in the weld seam zone are compacted. The weld seam becomes wider and squeezes to both sides, and then the heat-affected zone structure is coordinating deformation, resulting in an increase in dislocation density and achieving the strengthening effect for the "over-aged softening zone".

Key words: aluminum alloy, joint softening, laser induced arc, welding-rolling composite forming, partially deformation

中图分类号: