Shielding gas nozzle diameter variation and its impact on the anodic power distribution of low-current tungsten inert gas arcs were investigated, while maintaining either shielding gas flow rate or flow velocity constant. In addition, the effects of anode surface condition and flow behaviour type (laminar or turbulent) caused by the shielding gas nozzle applied were studied. It was found that arcs of 50 amperes (A) welding current were highly unstable deploying the conditions used, while increasing the arc electrical current to 100 A led to improved arc stability. As found in previous investigations, non-Gaussian distribution profiles occurred at 50 A, even with improved shielding. The power density maxima were found shifted away from the arc axis.

中文翻译：

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保护气体喷嘴设计对小电流TIG焊接电弧功率密度分布的影响

研究了保护气体喷嘴直径的变化及其对小电流钨极惰性气体电弧阳极功率分布的影响，同时保持了保护气体的流量或流速恒定。此外，还研究了使用保护气体喷嘴对阳极表面状况和流动行为类型（层流或湍流）的影响。发现在使用条件下，焊接电流为50安培的电弧非常不稳定，而将电弧电流增加到100 A则可以提高电弧稳定性。如先前的研究发现，即使屏蔽得到改善，在50 A时也会出现非高斯分布。发现功率密度最大值偏离弧轴。