Damage and recovery in neutron-irradiated -phase Al56Ti44 were studied by means of positron annihilation lifetime spectroscopy. It was found that the recovery could be divided into 2 stages. The first stage, below 660K, was attributed to the migration of point defects. The second stage, at temperatures above 660K, was attributed to the dissolution of secondary defects which formed during the first stage. The main defects which were produced by neutron irradiation were collapsed planar aggregates of point defects. Some non-collapsed vacancy clusters were also created, but consisted of only a few vacancies and almost disappeared at temperatures below 700K. Neutron-irradiated material recovered to the fully annealed state at temperatures below 960K.

Y.Shirai, H.Kohda, T.Murakami, M.Yamaguchi, H.Kodaka: Intermetallics, 1996, 4[2], 139-42