Surface modification of Zr-based bulk amorphous alloys by using ion irradiation

Surfaces of the Zr_0.65Cu_0.18Ni_0.09Al_0.08]₉₈M₂ (M = Er and Gd) bulk amorphous alloys were modified by irradiation with energetic singly charged argon (Ar⁺) ions. Samples of both the alloys were irradiated with 2.17 × 10¹⁷ argon ions of 10 keV energy. As cast and ion irradiated samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Mechanical properties like Vicker's hardness, nanohardness, elastic modulus and elastic recovery were measured. Considerable increase in elastic modulus and hardness was observed because of ion irradiation in these alloys. The ion irradiated samples of the Zr_0.65Cu_0.18Ni_0.09Al_0.08]₉₈Er₂ alloy showed better properties as compared to Zr_0.65Cu_0.18Ni_0.09Al_0.08]₉₈Gd₂ alloy. CuZr₂ phase was detected in ion irradiated alloys by XRD and confirmed by EDS. The range of Ar⁺ ions was found to be approximately 9.3 ± 5.4 nm in both alloys.