IRRADIATION EFFECTS ON MICROSTRUCTURE AND TENSILE BEHAVIOR OF POLYCRYSTALLINE NICKEL

The microstructural modifications due to high energy electrons (8–18 MeV) and their correlation with the yielding behavior of polycrystalline nickel have been investigated. The specimens in the form of strips were irradiated at room temperature for 15 min in the energy range 8–18 MeV using linear accelerator. The comparison of microstructural results of irradiated specimens with that of the un-irradiated ones reveals that radiation deteriorate the surface of the target specimens. The damage was found to be more prominent at the grain boundaries. The tensile tests of both unirradiated and irradiated samples were carried out using Universal Testing Machine at room temperature. An increase in yield stress and loss of ductility was observed in case of irradiated specimens, which became more pronounced with an increase of incident beam energy. These effects are attributed to the interaction of glide dislocations stress fields with the defects produced during irradiation.