Published online by Cambridge University Press: 16 February 2011
Irradiation of large-grained Zircaloy-2 (Zy) and Zr-2.5Nb (ZN) with 1.5 MeV Ar+ ions to fluences of ≈ 1020/m2 (= 10-30 dpa) at 50, 300 and 420 °C, leads to enhanced ∝-phase Fe dissolution. Electron microprobe analyses showed ∝-phase Fe levels of 250-1500 ppma, compared to equivalent, non-irradiated state values of ≈ 70 ppma. In ZN the β-phase Fe levels fell from about 6000 to 3500 ppma: this result accords, qualitatively, with the loss of Fe from the β-phase following in-service neutron irradiation. Concentration vs depth measurements for Zy showed higher Fe levels towards the surface. Limited data for Ni in Zy show similar behaviour.