摘要
基于一种新型超快变换复合脉冲变极性电路变换拓扑,在正极性电流持续期间,叠加超音频直流脉冲方波电流,获得了过零无死区时间且具有快速电流上升沿和下降沿变化速率的复合超音频脉冲变极性方波电流,将其应用于铝合金的变极性TIG焊接过程,试验研究复合超音频脉冲方波变极性TIG电弧电学特性及其对铝合金焊缝成形等行为的变化规律.研究结果表明:超音频脉冲方波电流对变极性TIG电弧具有显著的收缩效应,电弧径向尺寸明显减小,在一定范围内提高脉冲电流频率,减小脉冲占空比,增加脉冲电流幅值,可提高铝合金焊缝熔透率,有利于改善和提高铝合金的焊接质量.
Based on a novel uhrafast convert hybrid pulse variable polarity main circuit topology, the ultrasonic pulse current which had a frequency of more than 20 kHz was superposed in the positive current duration to achieve the hybrid pulse variable polarity current which crossed zero with no dead time and with fast rising and falling edge. The effect of pulse current parameters on the arc characteristics and the behavior of aluminum alloy weld noted by the weld depth and width were studied. The experiment results show that the ultrasonic pulse current has a significant influence on the pinch effect of hybrid pulse variable polarity TIG arc, re- sulting in the obvious reduction of arc radial dimension. Increasing the pulse current frequency and amplitude as well as decreasing the pulse current duty cycle in special ranges, the weld melt rate is enhanced which may be beneficial to improve the weld quality of aluminum alloy obviously using hybrid pulse variable polarity TIG arc welding technique.
出处
《北京航空航天大学学报》
EI
CAS
CSCD
北大核心
2009年第8期1013-1017,共5页
Journal of Beijing University of Aeronautics and Astronautics
关键词
超快变换
超音频脉冲电流
变极性
电弧行为
收缩效应
ultrafast convert
ultrasonic pulse current
variable polarity
arc behavior
pinch effect
