Point defect production and annihilation in neutron-irradiated zirconium

High-purity Zr has been irradiated to a dose of 2.2 x 1021 n/m2 (E < 0.1 MeV) using the pulsed spallation source at IPNS. Electrical resistivity was monitored continuously during irradiation. The saturation resistivity, found from a linear extrapolation of the damage-rate curve between four and five nΩ.m. However, comparison with data from the literature shows that the normalized damage-rate curves from five experiments at different temperatures (less than or equal to 77 K) and with different neutron spectra, all fall on the same common curve. A saturation resistivity of 100 nΩ.m is found from the high-dose, linear part of this curve. A spontaneous recombination volume in the range 280 to 400 atomic volumes is found using the theory of Dettmann, Leibfried and Schroeder and the saturation resistivity of 100 nΩ.m. Post-irradiation annealing has been done up to 300 K using stepped, isochronal anneals. The recovery spectrum is in reasonable agreement with previous work, showing a large peak near 100 K, and two smaller peaks at 160 K and 250 K