Monolayer-thick TiO Precipitation in V-4Cr-4Ti Alloy Induced by Proton Irradiation

We have characterised to atomic resolution the mono-layer thick TiO-type precipitate induced by proton irradiation in V-4Cr-4Ti alloy at a dose of 0.3 dpa and a temperature of 350 °C. Its formation coincides with the coarsening radiation-induced interstitial a/2〈111〉 dislocation loops that are already present at 300 °C. The dislocation network induced by prior cold work is mostly recovered at 300 °C and 0.3 dpa, and is therefore expected to exert a minimal effect on the precipitate formation. This monolayer-thick precipitate constitutes an early stage in the radiation-induced aging process of V-4Cr-4Ti at low temperatures, and can potentially absorb additional light elements in reactor environments.