工艺参数对焊接等离子弧的影响

基于双区域近似电弧模型的理论，研究了工艺参数对喷嘴出口处转移型焊接等离子弧的影响，给出了喷嘴出口处等离子电弧的伏安特性曲线，以及在不同离子气流速和喷嘴直径的条件下，电弧的弧柱半径及压力随焊接电流变化的曲线，并与试验数据进行比较，比较结果表明，计算结果与试验测量值吻合良好。同时还分析了喷嘴直径、钨极内缩量以及离子气流速在相应的焊接电流下对等离子弧功率与电弧力的影响，并绘出曲线图。研究结果表明，对于中小电流规范下的转移型等离子弧焊接，采用双区域近似电弧模型来研究喷嘴出口处等离子弧的特性是可行的，该模型计算简便，可为得到高质量等离子弧焊接的设计及生产提供理论基础。

The Effect of Operating Parameters on Welding Plasna Arc

Based on a theory of an approximate two zone arc model,the effect of operating parameters on the transferred electric arc of the welding plasma was studied and curves of current voltage characteristics,arc radius and the pressures of the welding plasma at the nozzle exit,as a function of arc currents under a range of operating conditions,including varying plasma gas flow rates and different nozzle diameters,was showed,and the calculated results have been compared with experiments.The results showed that arc obtained from calculation is in good agreement with the measured values.Also,the influence of nozzle diameters,tungsten setback and plasma gas flow rate on the arc power and force of the welding plasma with the respective currents was analyzed,and curves are drawed.The study reveals that,as for the plasma over a range of miniature and medium arc currents,it is feasible to employ the approximate two zone arc model in studying the properties of transferred plasmas at the nozzle exit generated by the plasma welding process and that it is simple and convenient to calculated with the arc model,which can provide theoretic guidance for the design and manufacture of the plasma welding.