In the present work, the theoretical model of Wiedersich et al. is used to understand the mechanism of radiation induced Cr depletion and Ni enrichment at defect sites such as grain boundaries, surfaces and interfaces in 316SS. The... more
In the present work, the theoretical model of Wiedersich et al. is used to understand the mechanism of radiation induced Cr depletion and Ni enrichment at defect sites such as grain boundaries, surfaces and interfaces in 316SS. The coupled continuity equations for solute atoms, vacancies and interstitials are numerically solved to obtain best fits to the experimental depth profile of Cr and Ni in irradiated 316SS by varying the diffusivity coefficients. Numerical values of coefficients obtained by simulation are used to understand the microscopic mechanism of atomic transport. The values of the diffusivity coefficients obtained by solving the coupled continuity equations suggest that Cr depletes by diffusing via vacancies, whereas Ni atoms enrich at the grain boundary by diffusing via interstitials.
Coupled continuity equations for nitrogen atoms and vacancy fluxes are solved for known experimental conditions concerning the depth profiles of nitrogen implanted in copper at different energies and temperatures. It is observed that for... more
Coupled continuity equations for nitrogen atoms and vacancy fluxes are solved for known experimental conditions concerning the depth profiles of nitrogen implanted in copper at different energies and temperatures. It is observed that for implantations carried out at 200 ° C, nitrogen atoms possibly get trapped into vacancies during implantation and the vacancies tend to form clusters. The surface peak observed in depth profile data is shown to be due to Gibbsian segregation. The nitrogen diffusion coefficient is observed to be almost constant as temperature increases from-200 °C up to 200 o C.
