Optimizing GMAW parameters to achieve high impact strength of the dissimilar weld joints using Taguchi approach

Abstract

In this modern era, the joining of dissimilar metals is having a broader scope and applications in different field of engineering. The SA387 grade alloy steel plate is a pressure vessel steel grade, which is extensively used in high temperature applications such as boilers, heat exchangers, pressure vessels in oil and gas industries, and so on. Further, the requirement of joining SA387 with the stainless steel is needed in above mentioned applications at most of the times. Gas Metal Arc Welding (GMAW) is one among the extensively used method of welding in industries for joining different kind of metals. However, the process parameters namely, welding current, voltage, bevel angle are playing a pivotal role for obtaining a quality weld as well as for obtaining desirable mechanical properties. An effort is made in this study to optimize the welding parameters namely, welding current, voltage and bevel angle for obtaining better impact strength of dissimilar joining of SA387 alloy steel with the stainless steel grade of SS304 using Taguchi L9 orthogonal array. Further, ANOVA was carried-out to assess the most dominant process parameter which greatly influences the impact strength of the weld joint. The results evidenced that the welding current was the predominant parameter to distress the impact strength of the welded joint followed by welding voltage.