TiZr-base Bulk Metallic Glass with over 50 mm in Diameter

Low-cost TiZr-base bulk metallic glasses (BMGs) (Ti36.1Zr33.2Ni5.8Be24.9)(100-x)Cu-x (x=5, 7 and 9) with a maximum size of over 50 mm in diameter were developed by optimizing the alloy composition. The idea is initiated by selecting a particular microstructure comprising primary beta-Ti dendrite and amorphous phase. Afterwards, based on this composition of amorphous phase, a class of TiZr-base bulk metallic glasses was designed step by step to reach the optimum composition range. The glass transition temperature (T-g), initial crystallization temperature (T-x) and width of supercooled region (Delta T) of (Ti36.1Zr33.2Ni5.8Be24.9)(91)Cu-9 BMG are 611, 655 and 44 K, respectively. The (Ti36.1Zr33.2Ni5.8Be24.9)(91)Cu-9 BMG exhibits low density of 5.541 g.cm(-3) and high compressive fracture strength of 1800 MPa, which promises the potential application as structural materials.