The Effect of Welding Parameter on the Tensile and Impact Properties of Weldments

The mechanical performance of welded joints is significantly influenced by welding parameters, particularly welding current, which governs heat input, fusion quality, and metallurgical transformations. This study examines the effect of welding current on the tensile and impact properties of shielded metal arc welded (SMAW) mild steel joints. Standardized mild steel specimens were prepared and welded using E6016 electrodes at varying current levels (50A, 75A, 100A, 125A, 150A, 175A, and 200A) while maintaining a constant voltage of 220V. Mechanical tests, including tensile strength, impact resistance, and hardness evaluations, were conducted to assess the relationship between welding current and joint properties. The results reveal that moderate welding currents (125A–150A) produce weldments with superior mechanical properties, characterized by high ultimate tensile strength (UTS), favorable ductility, and balanced hardness. Lower currents (<75A) resulted in inadequate fusion, leading to weak joints with reduced strength and toughness. Conversely, excessively high currents (>175A) led to increased brittleness and reduced tensile strength due to grain coarsening and excessive heat input. The hardness test results further confirm that moderate current levels enhance both strength and wear resistance without compromising ductility. These findings emphasize the need for precise control of welding parameters to optimize joint integrity and mechanical performance. The study provides practical guidelines for selecting welding currents in industrial applications, ensuring enhanced weld quality and durability.