钨极氩-氮电弧行为及厚板紫铜冷焊的分析

采用水冷紫铜阳极和水冷TIG焊枪，在80～340A的电流范围内，对钨极氩-氮混合气体电弧的行为进行了测定和分析，主要测定和讨论了氩、氮及其不同配比混合气体电弧的静特性、电弧形态、阴极热功率、阳极热功率等内容。结果表明，当氮气含量较小时，电弧电压随氮气含量的增加明显增大，电弧阳极近区收缩明显，而阴极、阳极热功率所占比例却没有明显改变；当氮气含量超过20％以后，电弧电压及电弧阳极近区收缩现象越来越不明显。试验中使用TIG焊接方法，通过选择适当比例的氮气含量、焊接参数及工艺措施，可完全实现常温下中、厚紫铜试件的熔化和良好的焊缝熔深形状，并可获得满意的焊缝表面成形。

BEHAVIOR OF TUNGSTEN Ar-N2 ARC AND ANALYSIS OF THICK COPPER PLATE WELDING

Behavior of tungsten Ar - N2 arcs was measured by the water - cooling copper anode and TIG welding gun between 80 A to 340 A current range. Static character, shape, thermal power of anode and cathode of ares under different Ar - N2 gas ratio were measured and discussed. The results show that the arc voltage increased and region around anode decreased obviously as the content of N2 increasing when N2 content was low, while the ratio of thermal power at anode and cathode had little change. When the content of N2 exceeded 20 % , the region around anode decrease became obscure. Medium and thick copper plate can be melt, and enough melting depth and satisfactory welding shape can be achieved during TIG welding under atmospheric temperature by selecting suitable N2 ratio, welding parameters and technical measuremerits.