Characterization of gamma-ray irradiation influence on the corrosion behaviour of austenitic stainless steel

Abstract

This study investigates the effect of gamma irradiation on the corrosion behavior of austenitic stainless steel type AISI 304. Gamma-ray type 60Co gamma was used and three different of gamma radiation were applied on the samples: 75, 150 and 250 kGy. Different electrochemical corrosion tests were applied to measure the potentiodynamic polarization and plotting the electrochemical impedance spectroscopy. The results showed that the gamma radiation with doses 150 and 250 kGy increased the corrosion resistance, e.g. higher corrosion potential and less current density, however, the dose of 75kGy reduced the corrosion resistance, and local corrosion was observed on the irradiated samples. These results are attributed to the change in the chemical composition on the surface due to the irradiation. Elements such as chromium and oxygen are increased on the surface of high irradiated samples which led to enhancing the corrosion resistance, while impurities and ions of Cu, Zn, Cl and Na appeared on 75 kGy irradiated sample and led to localized corrosion.