Neutron irradiation damage in 64% cold-worked Titanium

Abstract

The crystal defects generated in 64% c.w. titanium by neutron irradiation have been investigated in detail. Cavities were found in 20% of the crystal grains. These were faceted on 101̄1 and (0001) planes and generally occurred in layers parallel with the (0001) plane. Annealing experiments showed them to be voids in character. Large faulted basal plane defects with 1 6 〈20 2 ̄ 3〉 displacement vectors were found in approximately 5% of all grains. These faults always had cavities associated with them and their formation was found to depend upon both the irradiation and the microstructure of the material. The 〈 a〉 -type dislocation loops were mainly vacancy in character with 1 3 〈11 2 ̄ 0〉 Burgers vectors. These loops were generally highly elliptical and aligned in rows parallel to 〈11̄00〉 and (0001). The ellipticity and alignment were found to cause anomalous interloop and intraloop fringe contrast under certain diffracting conditions.