Magnetic analysis of radiation enhanced diffusion in ferromagnetic nickel-beryllium alloys

5 μm foils of supersaturated ferromagnetic nickel-14.3 at –% beryllium have been irradiated at various temperatures between 120 and 200°C with 50 to 200 μA/cm2 electrons of 2.5 MeV. The precipitation of beryllium induced by the irradiation is determined from the variation of the magnetization vs. temperature curves with dose. The magnetic analysis yields the differential variation of the dissolved beryllium per beryllium concentration interval. Above 160°C the measurements show a linear dependence of the apparent radiation enhanced diffusion coefficient on the defect production rate and no effect on temperature variation. At lower temperatures the enhanced diffusion increases less steeply than linearly with the flux density and slightly with temperature. This behaviour turns up practically in any concentration region.