Corrosion resistance study of argon implanted and ion-beam-mixed 316 SS

The objective of the present work is to study and develop a suitable structural material for the Accelerator Driven Subcritical System (ADSS), which can withstand extreme conditions of irradiation in corrosive environment. Effects of radiation damage on corrosion resistance are evaluated and a possible solution is attempted by adding alloying elements such as Al or Si. Aqueous corrosion studies were carried out in 0.5 N H2SO4 solution on 316 SS, Ar+ implanted 316 SS, Al ion-beam-mixed 316 SS and Si ion-beam-mixed 316 SS. At a low dose 30 keV Ar+ implantation, the martensitic phase transformation was observed in 316 SS. Corrosion potential reduced to very low negative values after Ar+ implantation, indicating the reduction in corrosion resistance. As the dose was increased further, the corrosion resistance marginally improved. This correlates with the reduction in martensitic phase, as observed using glancing angle X-ray diffraction (GXRD). Si ion-beam-mixed 316 SS displayed good corrosion resistance with higher corrosion potential, higher pitting potential and large passive region, whereas Al ion-beam-mixed 316 SS displayed no passive region but had a higher corrosion potential.