摘要
目的研究不同脉冲磁场频率对铝/钢焊接接头结合质量的影响,实现铝/钢异种金属的高效焊接。方法采用脉冲磁场辅助CMT熔钎焊方法,对6061铝合金试板和Q235B钢板进行对接焊,通过光学显微镜、扫描电子显微镜和万能力学试验机等设备对铝/钢接头微观组织、力学性能和耐腐蚀性能进行分析。结果添加脉冲磁场后没有改变焊接接头的组织构成,焊缝主要由Al-Si共晶组织和α-Al固溶体构成。铝/钢界面层由θ-Fe2(Al,Si)5和τ5-Al7.2Fe1.8Si组成。随着脉冲磁场频率的增加,焊缝组织晶粒尺寸发生细化,当脉冲磁场频率为20 Hz时,Al-Si共晶组织尺寸最小。此时,接头的平均抗拉强度最大,为193.5 MPa。脉冲磁场频率大小对铝/钢接头耐腐蚀性能有一定影响。随着脉冲磁场频率的增加,接头的耐腐蚀性先升高后降低。当磁场频率为20 Hz时,铝/钢接头耐腐蚀性能最好。其实质是脉冲磁场频率影响界面层的IMC厚度,最终抑制了接头的电偶腐蚀。结论脉冲磁场频率大小可以影响铝/钢界面IMC层的厚度,添加合适的磁场频率可以进一步提高铝/钢界面的结合质量,接头的抗拉强度和耐腐蚀性均能得到提高。
The work aims to study the effect of different pulse magnetic field frequencies on the interface bonding quality of aluminum/steel welded joints,and realize efficient welding of aluminum/steel dissimilar metals.The butt welding of 6061 alu-minum alloy test plates and Q235B steel plates was carried out by pulsed magnetic field assisted CMT welding-brazing method.The microstructure,mechanical properties and corrosion resistance of aluminum/steel joints were analyzed by optical micro-scope,scanning electron microscope and universal mechanical testing machine.The microstructure of the welded joint was not changed after adding the pulsed magnetic field.The weld was mainly composed of Al-Si eutectic structure andα-Al solid solu-tion.The Al/steel interface layer was composed ofθ-Fe2(Al,Si)5 andτ5-Al7.2Fe1.8Si.As the frequency of the pulsed magnetic field increased,the grain size of the weld microstructure was refined.When the pulsed magnetic field frequency was 20 Hz,the size of the Al-Si eutectic structure was the smallest.At this time,the average tensile strength of the joint was 193.5 MPa.The pulsed magnetic field frequency affected the corrosion resistance of aluminum/steel joints.With the increase of the pulsed mag-netic field frequency,the corrosion resistance of the joint increased first and then decreased.When the magnetic field frequency was 20 Hz,the corrosion resistance of the aluminum/steel joint was the best.The essence was that the pulsed magnetic field frequency affected the IMC thickness of the interface layer,and ultimately inhibited the galvanic corrosion of the joint.The fre-quency of the pulsed magnetic field can affect the thickness of the IMC layer at the aluminum/steel interface.Adding a suitable magnetic field frequency can further improve the bonding quality of the aluminum/steel interface,and the tensile strength and corrosion resistance of the joint can be improved.
作者
石晓辉
浦娟
许祥平
龙飞
饶嘉威
SHI Xiaohui;PU Juan;XU Xiangping;LONG Fei;RAO Jiawei(Xinxiang Qixing Brazing Technology Co.,Ltd.,Henan Xinxiang 453010,China;School of Intelligent Manufacturing and Control Engineering,Shanghai Polytechnic University,Shanghai 212009,China;School of Materials Science and Engineer-ing,Jiangsu University of Science and Technology,Jiangsu Zhenjiang 212003,China;Institute of Materials,Henan Academy of Sciences,Zhengzhou 450052,China)
出处
《精密成形工程》
北大核心
2025年第6期119-128,共10页
Journal of Netshape Forming Engineering
基金
河南省科学院高层次人才科研启动项目(241820062)。
关键词
CMT熔钎焊
脉冲磁场
铝/钢异种金属
微观组织
腐蚀性能
CMT welding-brazing
pulsed magnetic field
Al/steel dissimilar metals
microstructure
corrosion resistance
