Effect of Welding Parameters on the Quality of Weldment in Arc Welding

Abstract

Welding is a permanent joining process, is widely used in every field of engineering. Different welding process used for various application such as automobile, ship building, power plant, construction ,pipe line etc. As the welding condition have great influence on the quality of weldment. So it is essential to study the mechanical properties of the weld ment for a better weld design. The present work investigates the effect of process parameter in arc welding of mild steel plate on the quality of weldment. Arc welding process is carried out on 5mm, 6mm and 8mm thick mild steel plate with variable current of 90A,100A, and 110 A. The mechanical properties like the toughness, tensile strength, micro hardness and the micro structure of the weld joint is evaluated. The investigation reveals that as the welding current increases from 90 to 110A the depth of penetration increases. The increase in the temperature of the weld joint results in decrease in hardness, tensile strength, impact strength and also affected the microstructure of the weld. As the current increases the heat input also increases which results in formation of coarse structure. The coarse grain structure formed having lower hardness, tensile strength and toughness value.