Minimization of corrosion rate using response surface methodology

In this paper, the corrosion rate of the austenitic stainless steel AISI 304 has been assessed via potentiodynamic polarization under the synergistic effects of environmental factors. Concentration of inhibitors, immersion time and concentration of HCL are the factors that induce the corrosion rate of the considered metal. Response Surface Methodology (RSM) is used in this research as an optimization method. The method design used is Central Compoite Design (CCD). The findings of this study reveal the combination of those three environmental factors in minimizing corrosion rate. This analysis calculates the contribution value of each parameter in changing the value of corrosion rate in both individual and synergistic cases. It has been found that minimum corrosion rate is achieved at inhibitor concentration combination of 6000ppm in 65 days and at HCl concentration of 0.5M. From the variation combination, it is seen that the concentration of inhibitor is adsorbed on the AISI 304 surface. The long period of immersion time supports the forming of thin layer which reduces the corrosion rate.