2025-03-29https://repository.covenantuniversity.edu.ng/handle/123456789/36949The effect of allium cepa extract as an inhibitor on mild steel corrosion in 0.5M H2SO4 was investigated at ambient temperature. The experiments were performed with gravimetric and potentiostatic polarization measurement methds. Polarization measurement was performed using a potentiostat (Autolab PGSTAT 30 ECO CHIMIE) interfaced with a computer for data acquisition and analysis. Corrosion inhibition of the extract on the steel test specimens in the different concentrations of H2SO4 used was achieved, though not very significant. There was increasing inhibition performance with increasing concentration of the extract inhibitor. The 80% onion concentration gave the best inhibition performance. A mixed type inhibitor is indicated with the results of ba and bc. A good correlation of results was obtained for the weight loss and polarization experimentapplication/pdfTJ Mechanical engineering and machinery, TP Chemical technologyArticle