• CN:11-2187/TH
  • ISSN:0577-6686

机械工程学报 ›› 2017, Vol. 53 ›› Issue (4): 26-33.doi: 10.3901/JME.2017.04.026

• 异种材料的焊接与连接 • 上一篇    下一篇

钢/铝异种金属激光焊接头界面特性的研究*

王晓虹, 谷晓燕, 孙大千   

  1. 吉林大学材料科学与工程学院 长春 130022
  • 出版日期:2017-02-20 发布日期:2017-02-20
  • 作者简介:

    王晓虹,女,1990年出生。主要研究方向为异种金属的连接。

    E-mail:584497342@qq.com

    谷晓燕(通信作者),女,1979年出生,博士,副教授,硕士研究生导师。主要研究方向为先进材料连接、异种材料的连接。

    E-mail:guxiaoyan@sina.com

  • 基金资助:
    * 国家自然科学基金资助项目(51275204); 20160712收到初稿,20161101收到修改稿;

Research on Interface Characteristic of Laser Welding Joints of Steel/Aluminum Dissimilar Materials

WANG Xiaohong, GU Xiaoyan, SUN Daqian   

  1. College of Materials Science and Engineering, Jilin University, Changchun 130022
  • Online:2017-02-20 Published:2017-02-20

摘要:

在环境污染日益严重的今天,汽车轻量化已成为当今社会亟待解决的问题,而钢/铝异种金属的焊接结构正是实现汽车轻量化的有效手段之一。激光焊具有焊接速度快、能量密度高、焊接变形小等特点,因此采用激光焊对钢/铝异种金属进行焊接。研究结果表明,当焊接速度为20 mm/s、焊接功率为0.82~0.83 kW时,采用“钢上铝下”的搭接形式可获得成形良好的焊接接头。未添加中间层的接头界面处存在连续分布的及岛状的金属间化合物区,其组织主要为Fe3Al、FeAl、FeAl2、Fe2Al5和FeAl3,其中部分FeAl3呈针状形貌。添加Fe-B-Si中间层的钢/铝界面金属间化合物区边界趋于平整,厚度减少,且岛状区和针状FeAl3数量减少。通过拉剪试验证明,Fe-B-Si中间层的添加可提高接头的力学性能。

关键词: 05CuPCrNi耐候钢, 断口形貌, 激光焊, 微观组织, 6082铝合金

Abstract:

With increasingly serious environmental pollution, automotive lightweight has become an indispensable problem to be solved, and using welding structure of dissimilar metal for steel/aluminum is an effective means to solve the problem of lightweight. Due to rapid speed, high energy density and small deformation, laser welding is regarded as one of prospective methods to join steel to aluminum successfully. It is shown that when welding speed and laser power are 20 mm/s and 0.82-0.83 kW with steel above Al alloy, the formation quality of the lap joint between steel and aluminum joint without interlayer is well. The continuous and island Fe-Al intermetallic compounds forming at the interface of the welded joint are Fe3Al, FeAl, FeAl2, Fe2Al5, FeAl3, and some of FeAl3 show needle-like morphology. When Fe-B-Si is used as interlayer, the interface is more flat, the thickness of Fe-Al intermetallic compounds becomes thinner and the number of island zone and needle-like FeAl3 decreases. The tensile-shear testing shows that the addition of Fe-B-Si can improve joints’ mechanical property.

Key words: 05CuPCrNi weathering steel, fracture morphology, laser welding, microstructure, 6082 aluminum alloy