Effects of γ-irradiation and Deformation Temperature on Tensile Properties of Pb-2 mass% Sb Alloy

Effects of γ-irradiation and deformation temperature (T) on the tensile properties of Pb-2 mass% Sb alloys were studied. The samples were annealed at 458 K for 2 h in air, then water quenched after they were γ-irradiated (the different doses were 0.5, 1.0, 1.5, and 2.0 MGy). The tensile properties were performed using stress-strain measurements at a constant strain rate (1.2 × 10−3 s−1) and at different T (303 − 393 K). It was found that at constant dose, the fracture stress (σF) decreases while the fracture strain (ɛF) increases as T increases. At particular T, σF increases while ɛF decreases with increasing dose. The strain-hardening exponent (n), which is the slope of the relation between ln(σ) and ln(ɛ) of the parabolic part of the stress-strain curve, was determined and its values increase as T increases and decrease as the dose increases. The value of the activation energy increases as the dose increases from 0.07 eV for un-irradiated sample to 0.1 eV for the 2 MGy-irradiated sample. These values are in accordance with that needed for dislocation movement and ordering process. An interpretation of the results was given, based on the creation of point and line defects due to γ-irradiation, and that results in a distribution of beta phase (Sb-phase), leading to a difficulty in the movement of dislocations, so there is an increase in alloy hardness.