Effect of low energy argon ion irradiation on work function of AISI 304L stainless steel

The effect of low-energy Ar + ion irradiation on the work function of stainless steel AISI 304L (SS-304L) was studied by varying energy and fluence of Ar + ion. The irradiation of Ar + ions on stainless steel creates several vacancies in the target material which resulted a change in work function. The retarding field diode method was used for the measurement of work function. Results reveal work function decreases with an increase in ion energy (for fixed ion fluence) of irradiated Ar + ion. Furthermore, it was observed that at varying ion fluence (for fixed ion energy) the decrease in work function value was more prominently, but at higher fluence, it again increases. In both (energy and fluence) cases of irradiation, the displacement per atom (DPA) in the material has been estimated with the stopping range using the SRIM-2013.00 program and is correlated with the experimental observation. Overall, the maximum work function was observed to be decreased by ~ 7.28% relative to the pristine sample in the case of fluence variation keeping the energy constant at 30 keV. The results indicate that low-energy ion irradiation can be utilized for work function modulation of materials and can be optimized by controlling ion fluence. The results are useful for further understanding of corrosion rate of materials and the data are extremely important for various nuclear reactors, where these materials are used.