The effects of welding current and purging gas on mechanical properties and microstructure of tungsten inert gas welded aluminum alloy 5083 H116

Abstract

Aluminum alloy 5083 H116 has an exceptional performance in extreme environments, moderately high strength, outstanding corrosion resistance in salt water and high impact strength at cryogenic temperature. In the present study, Aluminum alloy AA 5083 H116 plates were joined by tungsten inert gas (TIG) process by single and double sided welding. Welding current used was 53 A and 80 A with the addition of purging gas during welding process. The effects on micro structure and mechanical properties like surface hardness and tensile strength of the welded region were studied. The results have shown that optimum current out of the two weld current used is 53 A. Better microstructures, tensile and hardness were found in the welded joint for the weld current 53 A where the tensile obtained in the softened zone was approximately 87% than that of the base metal (BM). With increasing of TIG current, the width of PMZ increased. In addition, the doubled sided welding sequence also produced broader PMZ area.