Study of irradiation damage induced by He~(2+) ion irradiation in Ni_(62)Ta_(38) metallic glass and W metal

摘要

Metallic glasses are considered to possess good resistant against irradiation due to their inherent structural long-range disorder and a lack of grain boundaries. The He~(2+) with an energy of 300 keV was used to irradiate Ni_(62)Ta_(38) binary metallic glass to investigate its resistance against the irradiation, and the irradiated behaviour of the metallic glass was compared with that of W metal. The irradiation fluence range over 2.0 × 10~(17) ions/cm~2-1.6 × 10~(18) ions/cm~2. The TEM results show that nanocrystals of μ-NiTa phase and Ni_2Ta phase appeared in Ni_(62)Ta_(38) metallic glass under the irradiation fluence of 1.6 × 10~(18) ions/cm~2. The SEM results show that the surfaces of Ni_(62)Ta_(38) metallic glasses maintained flat and smooth, whereas a large area of blisters with peeling formed on the surface of W metal at the irradiation fluence of 1.0 × 10~(18) ions/cm~2. It indicates that the critical irradiation fluence of surface breakage of the Ni_(62)Ta_(38) metallic glass is higher than that of W metal. After the irradiation, stress was generated in the surface layer of W metal, leading to the increase of the hardness of W metal.