Effects of carbon ions irradiation on the electrochemical response of AISI 304 stainless steel

Austenitic stainless steel (AISI 304 SS) samples were irradiated with carbon ions of energies 0.25 MeV, 0.5 MeV and 1 MeV at constant dose (1 x 10(15) ions cm(-2)) by using Pelletron Accelerator. The electrochemical testing of the samples was performed by using open circuit potential (OCP), potentiodynamic polarization (PP) and electrochemical impedance spectroscopic (EIS) techniques. The OCP results showed more negative potential at 0.25 MeV as compared to the unirradiated sample, however, with increase of ions energy to 0.5 MeV and 1 MeV, the potential became more positive. The lowest corrosion current (3.380 mu A cm(-2)) and corrosion rate (1.450 mpy) was found for the specimen irradiated with 0.5 MeV carbon ions. The EIS results indicated an increase in the charge transfer resistance of the irradiated sample at 0.5 MeV as compared to the others. The scanning electron microscopy (SEM) analysis of the electrochemically tested samples was in agreement with the electrochemical results displaying lower pitting in the specimen irradiated with 0.5 MeV ions.