Selection and Mechanism of using active gas in GTAW Process – A review

Abstract

Gas tungsten arc welding process is known for its good quality welds. However, the lack of penetration of the process leads to low productivity. Many techniques have been implemented in the past to improve the joint penetration and thereby the productivity of GTAW process. In one of the technique, active gas like Carbon dioxide, Nitrogen or Oxygen is used in some proportion along with the inert gas. This addition of active gas can reverse the Marangoni induced surface tension flow to improve the weld bead penetration. This paper presents the brief report of work done by researchers to improve the GTAW productivity by using active gas in GTAW process. The effect of Active gas on weld bead geometry, metallurgical behavior, mechanical properties has been discussed herewith.