BCC金属Nb的重离子辐射损伤研究

STUDY OF HEAVY ION INDUCED RADIATION DAMAGE IN BCC METAL Nb

采用81 MeV碳离子辐照,模拟中子注量为10^(23)/cm^2的堆中子在Nb中产生的辐射损伤,用时间微分扰动角关联和正电子湮没二种方法研究辐射损伤及其高温退火效应。实验发现经注量2.5×10^(16)/cm^2的碳离子辐照后,在BCC金属Nb中产生单空位和双空位二种缺陷。随退火温度升高,双空位分解,单空位的总浓度逐步减小,经过1058K退火后,在Nb中由辐射损伤造成的缺陷消失。

Radiation damage in Nb produced by reactor neutrons of 10^(23) n/cm^2 fluence is simulated by 81 MeV carbon ion irradiation. The induced radiation damage and its thermal annealing behaviour are studied by both time differential perturbed angular correlation and positron annihilation techniques. The results show the existence of mono- and divacancies in BCC metal Nb following the 81 MeV carbon irradiation with a total dose of 2.5×10^(16)cm^(-2). As annealing temperature increases, divacancies are dissociated and total concentration of monovacancies decreases. After annealing at 1058 K, defects in Nb resulted from radiation damage completely disappear.