Irradiation swelling of Zr3Al

Heavy ion (0.5–2 MeV Ar⁺) and 1 MeV electron irradiation of Zr₃Al have established that the lattice parameter is increased by ~0.5% upon irradiation disordering and that the specific volume is increased by ($\text{5 ± 1}$) % following an irradiation-induced crystalline to amorphous transformation. These effects have been incorporated into a quantitative model of irradiation swelling which is shown to be in reasonable qualitative and quantitative agreement with fast-neutron induced dimensional changes in Zr₃Al. The model predicts that swelling will saturate and that the largest changes will occur at low temperatures.