论文部分内容阅读
针对钨极氩弧焊(TIG)电弧高频引弧存在易破坏其周围设备、危害人体健康等问题,提出了采用激光等离子体引燃TIG电弧的新方法。以峰值时间为10 ms的CO2脉冲激光进行TIG电弧的引弧试验,并采用高速摄像观察了激光等离子体引燃TIG电弧过程中的等离子体形态。试验结果表明,激光等离子体的形态和大小是引弧成功与否的关键因数之一,只有当激光等离子体接触到钨极导致电极与工件之间的间隙被导通产生电子发射并形成自持放电时才能引燃电弧。在此基础上,进一步研究了保护气体成分、工件材料、激光束离焦量以及保护气体流量等因数对激光等离子体引弧性能的影响规律。
Aiming at the problems of high frequency arc ignition in TIG arc, such as easily destroying the surrounding equipment and endangering human health, a new method of igniting TIG arc by laser plasma was proposed. The arc ignition test of TIG arc was carried out with CO2 pulsed laser with a peak time of 10 ms, and the plasma morphology during ignition of TIG arc by laser plasma was observed by high-speed imaging. The experimental results show that the shape and size of the laser plasma is one of the key factors for the success of arc ignition. Only when the laser plasma contacts the tungsten electrode causes the gap between the electrode and the workpiece to be turned on to generate electron emission and form self-sustained discharge When it can ignite the arc. On the basis of this, the influences of the factors of shielding gas composition, workpiece material, laser beam defocusing and shielding gas flow on the arc ignition performance of laser plasma are further studied.