Volume 7, Issue 1 (January 2010)
Influence of Neutron Irradiation on Energy Accumulation and Dissipation during Plastic Flow and Hardening of Metallic Polycrystals
Deformation-calorimetric experiments have been performed on specimens of Armco iron, pure nickel, and two austenitic chromium-nickel alloys: 12Cr18Ni10Ti and 03Cr20Ni45Mo4Nb, each tested in both unirradiated and irradiated conditions. It has been shown that for neutron-irradiated 12Cr18Ni10Ti stainless steel and also for nickel and Armco iron, the latent energy (Es) versus σ curves shift towards lower values of Es, and these curves progressively lose their parabolic appearance that is typical for unirradiated metals and alloys. It has also been shown experimentally that “excess heat” is measured when stored energy associated with radiation-produced defect agglomerates is released during their annihilation in formation of defect-free channels. In effect more energy in released than the mechanical energy supplied externally to cause deformation of the specimen. When post-irradiation annealing is used to reduce the concentration of defect agglomerates, the excess energy phenomenon disappears.