摘要
为了提高压印连接接头的强度,改善电阻点焊对铝合金连接不稳定的问题,对5052铝合金压印-电阻点焊复合连接的可行性进行了探究性试验。在焊接时间和焊接压力保持不变的情况下,将焊接电流(23-27 k A)视为唯一变量,探究了焊接电流的最优值。利用超声波水浸聚焦入射法对复合连接接头的成形性进行了检测;使用MTS材料试验机对试样进行了拉伸-剪切试验,得到了压印-电阻点焊复合连接接头的最大静拉伸载荷、失效形式及能量吸收值。结果表明:压印-电阻点焊复合连接可以实现对5052铝合金接头的有效连接且接头形貌可以利用超声C扫描进行检测;在焊接时间和焊接压力不变的情况下,适当增大焊接电流,接头的最大静拉伸载荷和能量吸收能力均有所提高,焊接电流的最优值均为25 k A;当焊接电流继续增加,接头内部结构遭到破坏。
To improve the joint strength of the clinch connection and the instability of the resistance spot welding to aluminum alloy connection,the feasibility study of the 5052 aluminum alloy clinch-resistance spot welding hybrid process connection was carried out. When the welding time and the welding pressure remained unchanged,the welding current( 23-27 k A) was taken as the only variable factor to explore the optimal value of the welding current. The formability of the hybrid connection joint was tested by ultrasonic water immersion focusing method. The maximum static tensile load,the failure mode and the energy absorption value of the clinch-resistance spot welding hybrid connection joint were obtained by tensile and shear tests on MTS material testing machine. The results show that the clinch-resistance spot welding hybrid connection can effectively connect the 5052 aluminum alloy joint,and the joint morphology can be tested by ultrasonic C scanning. When the welding time and the welding pressure remain unchanged,the maximum static tensile load and energy absorption capacity of the joint can be improved by appropriately increasing the welding current,and the optimal value of the welding current is 25 k A. When the welding current continues to increase,the internal structure of the joint is damaged.
引文
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