镁合金电阻点焊内部喷溅产生的原因分析
Study on inner expulsion in resistance spot welding of magnesium alloy
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摘要: 在电阻点焊过程中喷溅的产生直接降低焊接接头的强度,因此是最不希望出现的焊接缺陷。文中引入基于显微接触理论的接触电阻模型,通过轴对称有限元模型分析了镁合金电阻点焊过程中的温度场分布及塑性变形过程,以揭示内部喷溅产生的原因。结果表明,由于AZ31镁合金高热导率、低熔点、低比热容和大的线膨胀系数,焊接中需要采用大电流短时间的强参数焊接,所以相对于铝合金和钢铁来说,喷溅在镁合金焊接中更容易发生。内部喷溅产生的原因主要与金属熔化导致熔核内部压强增大相关,增加的压力致使周围的塑性环产生缺口,保护液态金属冲破周围固态金属的束缚,形成喷溅。Abstract: Expulsion is highly undesirable during the resistance spot welding for it decreases the weld quality. An axisymmetric finite element model was creates to study the distribution of temperature and the plastic deformation to investigates interior expulsion happening during the resistance spot welding of AZ31 magnesium alloy, employing a contact resistance model based on the micro-contact theory. Because of high thermal conductivity, low melting point,small specific heat and large linear thermal expansion coefficient of AZ31 magnesium alloy, expulsion is most encountered problem due to the application of high current in short welding time, compared with Al alloy and mild steel. And it is connected with the increased pressure in the nugget due to melting so that the surrounding solid material cannot hold the liquid phase and the molten metal break through the constriction of peripheral boundary, which leads to expulsion.
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Keywords:
- expulsion /
- magnesium alloy /
- resistance spot welding /
- finit element method
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期刊类型引用(15)
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2. Deer He,Nianchun Deng,Xiuning Peng. Numerical Simulation Analysis of Welded Joints in Arch Ribs of Large Span Steel Pipe Arch Bridges. Journal of Harbin Institute of Technology(New Series). 2024(03): 19-30 . 必应学术
3. 巨航瑞,冯伟,郭瑞鹏,柳春风,田晓阳,张光桥,赵建锋,杨国涛. 不等厚钢板对接焊缝焊接残余应力研究. 低温建筑技术. 2022(04): 86-91+103 . 百度学术
4. 罗家元,左进,张京辉. 车架用方钢T型接头焊接残余应力评估及焊接路径优化. 热加工工艺. 2021(15): 112-117 . 百度学术
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6. 胡效东,王吉涛,杨熠成,宋明,齐鹏飞. 304/Q345R复合板焊接接头微观组织及残余应力. 焊接学报. 2020(07): 39-45+99 . 本站查看
7. 李小兵. 基于不同热源模型的Q345钢中厚板焊接温度场数值模拟. 焊接技术. 2020(10): 19-21 . 百度学术
8. 叶日贵. 建筑钢箱梁节段接口环缝焊接变形研究. 钢结构(中英文). 2019(07): 95-99+69 . 百度学术
9. 林双平,钟振前,司红,李云玲,高群. 压力容器筒体焊接接头的开裂原因分析. 金属热处理. 2019(S1): 328-335 . 百度学术
10. 曹现雷,沈浩,徐勇,钟雯. Q800高强钢焊接工字形截面残余应力试验分析. 焊接学报. 2018(03): 36-41+130 . 本站查看
11. 刘剑桥,李滋亮,任森栋,梁伟,邓德安. 外部拘束条件下Q345钢单道堆焊接头面外变形机理的探讨. 机械工程学报. 2018(14): 90-97 . 百度学术
12. 房元斌,陆永能,张林杰,孔祥意. 稳态热加载对筒状结构变形和应力影响的研究. 焊接. 2017(03): 31-34+74 . 百度学术
13. 刘胜,楚锡华,徐远杰,何勇. 薄板T型焊残余应力数值模拟与试验研究. 热加工工艺. 2017(03): 238-241+245 . 百度学术
14. 周一俊,邓德安,刘晓占,毕涛. Influences of external restraint on welding distortion in low carbon steel bead-on thin plate joints. China Welding. 2017(01): 9-14 . 百度学术
15. 毛志涛,蒲晓薇,汪维登,叶延洪,邓德安. Q345钢激光焊与气体保护焊的焊接变形与残余应力对比. 中国激光. 2016(06): 125-134 . 百度学术
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