快变换超音频直流脉冲GTAW电弧行为

基于超音频直流脉冲钨极氩弧焊(GTAW,Gas Tungsten Arc Welding)电源输出脉冲电流沿变化率di/dt≥50A/μs的超音频直流脉冲方波电流,将其用于0Cr18Ni9Ti奥氏体不锈钢GTAW焊接过程,研究分析了焊接电弧特性、电弧力及焊缝熔透特性.结果表明:超音频直流脉冲方波电流参数对电弧电学特性、形态及电弧力产生显著影响,与常规直流GTAW相比,快变换超音频直流脉冲GTAW电弧表现出明显的收缩效应,焊缝熔深在一定范围增大,熔宽减小,平均电弧力大幅增长,焊接效率提高.

Fast-convert ultrasonic frequency pulse GTAW arc behavior

Based on ultrasonic frequency pulse gas tungsten arc welding(GTAW) power,the out current with di/dt≥50 A/μs for the ultrasonic fast current rate of rise and fall was achieved.The arc behavior was investigated in the use of ultrasonic frequency pulse tungsten inert-gas welding for 0Cr18Ni9Ti stainless steel,including the electrical characteristics of arc,the arc force and welds penetration rate.The experimental results show that compared with conventional direct current GTAW,arc plasma has an obvious pinch effect,and the arc force a huge increment with the effect of ultrasonic frequency pulse current.Similarly,the weld penetration of ultrafast frequency pulse GTAW could be improved with enhance of the arc force as the increasing depth of penetration and the decreasing weld width.It is beneficial to improve weld quality and effectively to achieve perfect welds of 0Cr18Ni9Ti stainless steel.