https://www.sciencescholar.us/journal/index.php/ijpse/issue/feedInternational journal of physical sciences and engineering2026-08-31T00:00:00+00:00Joan M.R. Diazijpse@sciencescholar.usOpen Journal Systems<p style="text-align: justify;"><strong>IJPSE</strong> is published in English and it is open to authors around the world regardless of the nationality. It is currently published three times a year, i.e. in <em>April</em>, <em>August</em>, and <em>December</em>.<br />p-ISSN: 2550-6951</p>https://www.sciencescholar.us/journal/index.php/ijpse/article/view/15977 Investigation of the effects of some input parameter on the tensile strength of mild steel using RSM2026-07-09T12:24:25+00:00Sunday Eyaefeeyasunnygee@gmail.comJ. I. Acheboeyasunnygee@gmail.comK. O. Obahiagboneyasunnygee@gmail.comC. E. Etin-Osaeyasunnygee@gmail.com<p>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).</p>2026-07-04T00:00:00+00:00Copyright (c) 2026 International journal of physical sciences and engineering