Consolidation of amorphous Ni-Zr-Ti-Si powders by vacuum hot-pressing method

In the current study, we investigated the feasibility of fabricating amorphous Ni₅₇Zr₂₀Ti₂₀Si₃ powders by mechanical alloying, and consolidating them into bulk metallic glasses by a vacuum hot pressing technique. The as-milled and hot-pressed samples were examined by X-ray diffraction, scanning electron microscope, and differential thermal analysis. According to the results, amorphous Ni₅₇Zr₂₀Ti₂₀Si₃ powders were prepared after milling elemental powder mixtures for 5 h. The amorphous powders were found to exhibit a wide supercooled liquid region of 88 K before crystallization. Bulk metallic glasses were prepared successfully by consolidating the as-milled Ni₅₇Zr₂₀Ti₂₀Si₃ amorphous powders using vacuum hot pressing in the supercooled liquid region. Vickers microhardnesses of the as-pressed samples are in the range of 788-830 kg/mm².