Formation of New Ti-based Metallic Glassy Alloys

Abstract

New Ti-based bulk glassy alloys were synthesized in a multi-component alloy system of Ti-Cu-Ni-Al-Zr-Si-B. In a wide composition range of Ti > 50 at%, single-phase glass rods with diameters up to 2.5 mm were prepared using a conventional copper-mold casting method. The new Ti-based glassy alloys show compressive strength above 1900 MPa. The plastic (serrated) strain under compression is lager than 0.01. The new Ti-based glass phase exhibits relatively high thermal stability with a large supercooled liquid region (ΔT_x) above 50 K. These glassy alloys, however, exhibit complex crystallization behavior characterized by multiple exothermic-reaction peaks on their differential scanning calorimeter (DSC) curves. The glass-forming ability of this complex system is discussed on the basis of knowledge available for bulk glass formation.