铝合金后中值波电流焊接工艺研究

发布时间：2018-09-05 14:26

【摘要】：一脉一滴的熔滴过渡被广泛认为是脉冲熔化极惰性气体保护焊中最好的过渡形式,通过在方波脉冲的峰值后增加一个后中值脉冲能有效增强熔滴过渡的可控性,提高焊接过程稳定性和焊缝成形效果.文中利用小波分析仪采集焊接过程瞬时电流电压信号,经过分析得到电流-电压分布概率和U-I图,并将两者与焊缝外观相结合一起综合评定焊接效果.1.2 mm铝合金ER4303焊丝焊接实验表明:在平均电流不变的情况下,采用后中值脉冲波形焊接能明显提高焊缝成形的质量,在焊缝表面形成规整的鱼鳞纹;中值电流取值太小,控制熔滴过渡的作用不明显,只是相当于增加了基值时间;取值太大,相当于增加了峰值时间,焊接过程不稳定;后中值时间太短,能量积累不够,不能控制熔滴过渡;时间太长容易造成熔滴过渡不规则,焊缝的鱼鳞纹消失;后中值电流时间取值在6~10 ms范围内,取值在强弱脉冲电流平均值左右时,焊接过程稳定,焊缝鱼鳞纹光亮、规整、美观.
[Abstract]:The droplet transfer from pulse to drop is widely regarded as the best transition form in pulsed inert gas welding. By adding a back median pulse after the peak of square wave pulse, the controllability of droplet transfer can be effectively enhanced. Improve the stability of welding process and weld forming effect. In this paper, the instantaneous current and voltage signals of welding process are collected by wavelet analyzer, and the probability of current-voltage distribution and U-I diagram are obtained by analysis. The welding experiment of ER4303 wire of 1.2 mm aluminum alloy combined with the welding appearance shows that the welding quality of the weld can be improved obviously by using the posterior median pulse waveform welding under the condition of constant average current. The median current is too small to control the droplet transfer, which is only equivalent to the increase of the base value time, the value is too large, equivalent to increase the peak time, the welding process is unstable, the value is too large, the value is too small, the effect of controlling droplet transfer is not obvious, the value is too large, the value is equivalent to increase the peak time, the welding process is unstable; The second median time is too short and the energy accumulation is not enough to control the droplet transfer, the time is too long to make the droplet transition irregular and the scale of weld seam disappear, the time of the posterior median current is within the range of 6 ~ 10 ms. When the value is about the average value of the strong and weak pulse current, the welding process is stable, the welding seam scales are bright, regular and beautiful.
【作者单位】：华南理工大学机械与汽车工程学院;
【基金】：广东省科技计划项目(2013B090600098) 广东省教育部产学研结合项目(2011B090400261) 黄埔区科技计划资助项目(201341) 广东省特派员工作站项目(2010B090500008) 佛山市科技计划项目(2011AA100175)~~
【分类号】：TG457.14

【参考文献】