Quench-hardening and neutron-irradiation hardening in zirconium

The effect of high temperature quenching from both α and β phases and neutron irradiation on the tensile strength of zirconium has been investigated. It is found that the quench temperature dependence of the increase in yield stress of zirconium both for α and β phases can be represented by a linear log Δ degvs/Tq relationship. The temperature dependence of Y.S. of β-quenched specimens shows that the change in Δ deg is largely 'athermal' in nature. The increase in Y.S., the recovery behaviour and thermally activated deformation of neutron irradiated zirconium are discussed. Thin film electron microscopy of the quenched and irradiated zirconium foil has been carried out in order to correlate the defect structures with mechanical property changes. (author)