Structure and properties of molybdenum implanted with high-flux carbon ion

High purity molybdenum was implanted by C ion in a metal vapour vacuum arc (MEVVA) implanter. The influence of implantation parameters was studied by varying ion fluence and ion current density. The samples were implanted by 45 keV C ion with fluences from 1×1015 to 1×1018 ions/cm2, respectively. The as-implanted samples were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), and nanoindenter. Different morphologies were observed on the surfaces of the as-implanted samples due to irradiation damage, and clearly related to implantation parameters. XRD spectra confirm formation of β-Mo2C with ion fluences equal to or larger than 1×1016 ions/cm2, and formation of α-Mo2C with ion fluence of 1×1018 ions/cm2. The maximum nanohardness and maximum modulus of the as-implanted samples increased gradually with increasing ion fluence, and reached the corresponding maximum values with ion fluence of 1×1018 ions/cm2. The experimental results suggest that the structure and properties of the as-implanted Mo samples exhibited strong dependence on implantation parameters.