Evolution of Defects in two Titanium Alloys Under Ti²⁺Ion Irradiation

Abstract

The goal of this study was to understand the microstructural evolution of two industrial titanium alloys (grade 2 and 5) under irradiation in order to derive information for potential application in nuclear industry especially for internals in nuclear reactors. Ion irradiation conditions were chosen to obtain a homogeneous damage profile of a few dpa over 500 nm depth in six hours (corresponding to one irradiation day). The influence of both the dose and temperature was taken into account. A special attention paid to counting defects revealed an evolution with the dose, the temperature and the nature of the material. After 0.6 and 3 dpa irradiations at 450°C, using the JANNuS-Saclay facility, TEM characterization showed that a thin precipitation of rich vanadium -phase occured in the -phase of Ti6-4, in addition to the <a> loops present in both materials.