Preparation and mechanical properties of high strength Zr-based bulk metallic glasses containing high content of Cu

The novel Zr-Ti-Cu-Ni-Be metallic glasses and composite with different contents of copper prepared by inject casting method are presented. The compositions and microstructures of these alloys were analyzed by using XRD and SEM. And the thermal stability was studied with differential scanning calorimeter (DSC). It is revealed that the value of ΔT_x is increased gradually with the increase of copper content in Zr-Ti-Cu-Ni-Be alloys whereas the glass forming ability is decreased, indicating that ΔT_x could not characterize their glass forming ability. In contrast, it is found that the glass forming ability is much higher when the component is close to eutectic spot. The compression test reveals that increasing of the content of copper in Zr-Ti-Cu-Ni-Be alloys can improve the mechanical property of the alloy significantly. The compressive fracture strength as high as 2.2 GPa can be obtained for the Zr-Ti-Cu-Ni-Be metallic glass with 18.5% Cu.