A development of Ti-based bulk metallic glass

The thermal property, crystallization behavior, glass forming ability (GFA) and mechanical properties of Ti-based amorphous alloys were studied by using differential scanning calorimetry (DSC), X-ray diffractometry, transmission electron microscopy and compressive test. These alloys were developed systematically by considering atomic size and interaction parameters between constituting elements. Partial replacement of Cu by Be and Ti by Zr in Ti–Cu–Ni–Sn alloy improved the GFA. Fully amorphous rods, of diameter 2, 5 and 8 mm, could be fabricated by injection casting Ti50Cu25Ni15Sn3Be7, Ti45Cu25Ni15Sn3Be7Zr5 and Ti40Zr25Ni8Cu9Be18 alloys, respectively. The Trg(=Tg/Tl) and γ (=Tx/(Tg+Tl)) parameter shows a relatively good agreement with the maximum diameter of bulk glass, while ΔTx has poor relationship with the GFA of alloys. The bulk amorphous alloys exhibit high compressive strength of approximately 2500 MPa with good ductility.