Investigation of the effects of some input parameter on the tensile strength of mild steel using RSM

Eyaefe Sunday, Achebo J. I. , Obahiagbon K. O., Etin-Osa C. E — Sat, 04 Jul 2026 00:00:00 +0000

Tensile strength been a key measurement used by researchers, engineers, and quality control departments to evaluate the mechanical properties of a material, product, or component. This study aimed to investigate the effect of influence of welding current, voltage, and travel speed on the tensile strength for Gas Metal Arc Welding (GMAW) of mild steel using Response Surface Methodology . A Central Composite Design comprising twenty experimental runs was employed to systematically investigate the effects of three input factors: welding current (180–210 A), voltage (22–25 V), and weld speed (2.0–3.5 mm/s). Quadratic polynomial models were developed using Response Surface Methodology in Design-Expert software, Multi-objective optimization was performed using both the desirability function approach within RSM. All optimized parameter combinations were experimentally validated through confirmation runs, with statistical diagnostics including coefficient of determination (R²), adjusted R², predicted R², lack-of-fit tests, and residual analysis used to assess model adequacy and predictive reliability. Results showed RSM predictive accuracy a Tensile Strength 76.78%, . The optimization approaches converged to a consistent optimal parameter window (Current ≈194–195 A, Voltage = 25 V, Weld Speed ≈2.7–3.5 mm/s).

International journal of physical sciences and engineering

Investigation of the effects of some input parameter on the tensile strength of mild steel using RSM