Study of irradiation induced defects and phase instability in ß phase of Zr Excel alloy with in-situ heavy ion irradiation

Abstract

In situ heavy ion irradiation with 1 MeV Kr²⁺ was carried out to study irradiation induced phase change and atomic lattice defects in the ß phase of Zr Excel alloy. No decomposition of ß-Zr was observed under irradiation at either 200 °C or 450 °C. However, ω-Zr particles experienced shape change and shrinkage associated enrichment of Fe in the ß/ω interface at 200°C irradiation but not at 450 °C. The defectevolution in the ß-phase was examined with single phase Zr-20Nb alloy. It was found that dislocation loops with Burgers vector ½<111> and <001> both present in ß-Zr under room temperature irradiation.