Effect of Xe26+ ion irradiation on the microstructural evolution and mechanical properties of Zr-1Nb at room and high temperature

Zr-1Nb samples were irradiated with 6.37 MeV Xe26+ ions to 5 dpa at room and high temperature and the microstructural evolution and mechanical properties were investigated. After irradiation, X-ray diffraction (XRD) and slow positron annihilation technique (SPAT) were used to study the microstructure and the results demonstrated that the microstrain, domain size, dislocation density and vacancy-type defects increased. The less increases in these microstructural parameters are due to the annihilation of defects at high temperature irradiation. The presence of the defects are responsible for the enhanced hardness of irradiation at room or high temperature and activation energy of irradiation at room temperature. The reason of the lowest activation energy of irradiation at high temperature still needs further clarification.