中文摘要：

两倍防护 TIG 的效果(钨惰性的气体)火炬的结构的参数，包括在气体和电极的扩大长度的内部、外部的层之间的流动率比率(在这个工作作为 ELE 缩短了)，为 0Cr13Ni5Mo martensitic 不锈钢在熔化地区侧面上被调查了。结果证明双防护 TIG 进程产出焊接水池的相对高的穿入在大量结构的参数。在 3mm 上的 ELE 太大并且在电极的保护上引起不利反应。有有高氧内容的相对高的流动率或外部层的外部气体对溶解进弧的氧导致，它导致焊接水池表面和电极尖端的氧化。双防护 TIG 焊接了金属被测试并且介绍好影响性质。

英文摘要：

The effects of double shielded TIG （tungsten inert gas） torch＇s structural parameters, including the flow rate ratio between the inner and outer layers of gas and the extended length of the electrode （abbreviated as ELE in this work）, on the fusion zone profile have been investigated for OCrl3NiSMo martensitic stainless steel. Results show that the double shielded TIG process yields relatively high penetration of the weld pool in a broad range of the structural parameters. ELE over 3 mm is too large and causes adverse reactions on the protection of electrode. The outer gas with relatively high flow rate or the outer layer with high oxygen content is conducive to the oxygen dissolved into the arc, which results in the oxidation of the weld pool surface and the electrode tip. The double shielded TIG welded metal was tested and presented good impact property.