Microstructural evolution and point defect behavior in V, V–5Ti and V–4Cr–4Ti were examined by using a high voltage electron microscope. In order to examine the effects of interstitial impurity atoms, V–Ti alloys with different levels of purity have also been examined. During irradiation, interstitial-type dislocation loops formed and grew in all of the materials. In alloys, the loop number density (CL) was much higher than that in V. In high purity V–4Cr–4Ti, contrary to results from a previous study on V, CL did not significantly decrease or change by purification, indicating solute atoms themselves strongly trap self-interstitial atoms. From the temperature dependence of loop density in V–4Cr–4Ti, the effective migration energy of a self-interstitial atoms of 0.50eV was obtained. Various observed phenomena were discussed in terms of this activation energy.

Study of Point Defect Behavior in V–Ti Alloys using HVEM. T.Hayashi, K.Fukumoto, H.Matsui: Journal of Nuclear Materials, 2002, 307-311[2], 951-5