New Ti-Based Bulk Glassy Alloys with High Glass-Forming Ability and Superior Mechanical Properties

Ti-based glassy alloy rods with diameters up to 5 mm were prepared for Ti41.5Zr2.5Hf5Cu42.5Ni7.5Si1 in a multi-component system of (Ti, Zr, Hf)-(Cu, Ni)-Si by conventional copper mold casting. The new mutli-component glassy alloy exhibits moderate thermal stability with a supercooled liquid region (ΔTx) above 50 K. The glass transition temperature (Tg), crystallization temperature (Tx), melting temperature (Tx), liquidus temperature (Tl), and the reduced glass transition temperature (Tg/Tl) are 680 K, 730 K, 1143 K, 1199 K and 0.57, respectively. The cast glassy alloy exhibits compressive strength of 2080 MPa, tensile strength of 2040 MPa and Young's modulus of 100 GPa. The reason for the high glass-forming ability (GFA) of the Ti-based multi-component alloy is discussed on the basis of knowledge available for bulk glass formation.