2017 Volume 42 Issue 2 Pages 41-45
To investigate the thermal stability of the ion-irradiation induced amorphous state in bulk samples of Ni3Nb and Ni3Ta intermetallic compounds, they were irradiated with 16MeV Au ions at room temperature, and were subsequently annealed up to 773K and 973K, respectively. The lattice structures of the irradiated samples and the annealed samples were examined by means of the grazing incidence x-ray diffraction (GIXD). The hardness of the samples was also measured as a function of annealing temperature. The amorphous state induced by room temperature irradiation recovers to the intrinsic ordered structure for Ni3Nb samples at 773K. On the other hand, for Ni3Ta samples, the irradiation-induced amorphous state doesn’t recover to the intrinsic ordered structure even at 973K, but it changed to another lattice structure by the subsequent annealing. The values of the hardness decreased by the subsequent annealing. For Ni3Nb samples, the irradiation at elevated temperatures was also performed. The higher temperature irradiation tends to suppress the amorphization more strongly in Ni3Nb samples. As a result, the increase in hardness becomes smaller for the higher temperature irradiation.
