Comparative Evaluation of Shielded Metal Arc Welding and Gas Tungsten Arc Welding on Stainless Steel Joints

Samuel Onifade, Olubunmi Sogunro & Victor Ogundemuren, Volume 7 Issue 1, July 2026 Pages 47-60, Published: 2026-06-24

Abstract

In the present study, Shielded Metal Arc Welding (SMAW) and Gas Tungsten Arc Welding (GTAW) were investigated comparatively in the joining of AISI 304 stainless steel. A detailed analysis of tensile strength, hardness profile, microstructure features, quality of weld, and cost analysis was carried out. The experimental work included tensile testing, Vickers hardness test, and microscopic evaluation under controlled welding parameters. Statistical analysis by ANOVA was carried out to find the significant difference between the two welding processes. The results indicate that GTAW welded joints have higher tensile strength (590-600 MPa) than SMAW welded joints (470-480 MPa), high hardness, and fine microstructure. Analysis of Variance results (F = 288) show that there is a statistically significant difference between the two welding processes. Fine equiaxed structure and fewer defects were observed in GTAW joints, and coarse-grained and slag inclusions were present in the SMAW welded joint. Although SMAW has relatively low initial and carrying cost, GTAW shows good economic benefits and high weld quality. The conclusion is GTAW welding process is best suited for applications where the quality of the weld and mechanical properties are significant, and SMAW is for less significant applications with portability and low cost