The Eeffect of Arc Length and Shield Gas on Penetration Aspect Ratio in A-TIG Welding

Abstract

TIG welding enables to produce high quality weldment. However it has some problems such as shallow penetration and large distortion due to low penetration aspect ratio after welding. In order to overcome those problems, there are many ongoing studies on A-TIG welding, which use active flux. In this study, the effect of arc length and shield gas on penetration aspect ratio with melt-run welding on STS 304 6t, on which active flux was spreaded, was investigated. Arc length was changed from 1mm to 3mm, and aspect ratio became higher as arc length was decreased in this range. 100% Ar gas, Ar-H2 mixed gas, Ar-He mixed gas, and 100% He gas were used as shield gas in this study. When Ar-H 2 mixed gas, Ar-He mixed gas, and 100% He gas were applied, penetration and melting efficiency were both increased as compared with 100% Ar gas. Aspect ratio was the highest with Ar-2.5% H2 mixed gas.

Welding Characteristics of A-TIG Using Various Compositions of Active Fluxes

“…C-TIG용접과 A-TIG용접의 용융효율 변화를 해석적으로 측정한 연구 사례가 있었으며 3) , 아크길이와 쉴드 가스의 변화에 따른 A-TIG용접의 효과에 대한 연구도 보고되고 있다 4) . 전반적으로 A-TIG용접에 대 한 연구는 스텐레스강에 대하여 활발히 진행되었으나 탄소강에 대해서는 연구가 부족한 실정이다 5) .…”