• CN:11-2187/TH
  • ISSN:0577-6686

›› 2014, Vol. 50 ›› Issue (12): 83-88.

• 论文 • 上一篇    下一篇



  1. 兰州理工大学机电工程学院;兰州理工大学甘肃省有色金属新材料省部共建国家重点实验室
  • 发布日期:2014-06-20

5056 Aluminum Alloy and Coated Steel Overlapped Fusion Welding-brazing by Laser with Preset Filler Powder

YU Shurong; JIANG Kai; FAN Ding   

  1. Mechanical and Electrical College, Lanzhou University of Technology
  • Published:2014-06-20

摘要: 针对铝/钢焊接的技术难点,采用预置金属粉末的办法,对5056铝合金与ST04Z镀锌钢板进行CO2激光搭接熔钎焊,分析熔钎焊接头成形、接头连接界面的显微组织及其力学性能。结果表明,选择合适的焊接参数,涂粉后能够实现铝合金与镀锌钢的优质连接;熔钎焊接头没有明显的针状Al-Fe金属间化合物向熔化区析出,且最大厚度小于10 µm,在熔化区边缘和熔化区与铝合金结合处熔钎焊根部出现两个富Zn区,Si、Zn、Mn、Mg等元素与Fe和Al或直接形成化合物,或形成固溶物,抑制了Al与Fe直接接触形成脆硬的金属间化合物;接头拉伸试样断裂形式有母材热影响区断裂和焊缝处断裂两种,焊缝处断裂面在铝熔化区一侧,接头平均机械抗力达190 N/mm,约为母材的85.2%。采用此方法可减小铝/钢熔钎接界面过渡层厚度,获得力学性能良好的熔钎焊接头。

关键词: 激光焊接;铝/钢;熔钎焊;金属间化合物

Abstract: In view of the technical difficulties of aluminum/steel welding, CO2 laser fusion welding-brazing is used to produce lap joint between 5056 aluminum alloy and ST04Z galvanized steel with filler powder. Weld appearance, microstructure and mechanical properties of welding joint are studied. The results show that high quality welding joint can be obtained by using the appropriate welding parameters with preset filler powder. The intermediate layer thickness is less 10 µm, and acicular intermetallic compound is not separated out to melted aluminum alloy. There are two rich Zn zones during fusion joint, which are located at melted edge and welding-brazing root. Si,Zn,Mn and Mg elements constitute compounds or solid solution with Al and Fe elements, which rigid intermetallic compounds are stopped to generate by restraining Al and Fe elements direct contact. Tensile specimen fracture mainly in the aluminum alloy heat affected zone or welds, and Welds fracture surfaces are all at the side of the aluminum melting area. The average mechanical resistance of 190 N/mm is obtained, about 85.2% of the base metal of 5056 alloy. By using this laser fusion welding-brazing method and filler special powder,the thickness of intermetallic compounds layer can be decreased and the fusion welding-brazing joints with excellent mechanical properties can be obtained.

Key words: laser welding;aluminum alloy and steel;fusion welding-brazing;intermetallic compounds