Compositional redistribution in Fe-Ni-Cr alloys under proton irradiation

The compositional redistribution in the direction of depth in austenitic Fe-Ni-Cr-Si-C alloys under 200-keV proton irradiation was examined experimentally using the cross-section technique. After the solution-annealed Fe-25.5Ni-14.7Cr-0.97Si-0.026C and Fe-25.7Ni-14.5Cr-2.85Si-0.026C alloys were irradiated at 873 K by 200-KeV protons to the dose of 175 dpa at the peak-damage position for the different irradiation times of 0.1 and 1.37 Ms, the depth profile of composition was measured with an energy dispersive X-ray microanalyzer. Significant depletion of nickel and enrichment of chromium were observed in the peak-damage region ranging from about 0.85 to 1.05 μm in depth, similarly in both the short-time (0.1 Ms) and long-time (1.37 Ms) irradiations. Slight enrichment of iron and slight depletion of silicon were also observed in the peak-damage region. The observed compositional changes in the peak-damage region is in good qualitative agreement with theoretical prediction, although some quantitative discrepancies between them remain