Impact fracture energy of bulk amorphous Zr55Al10Cu30Ni5 alloy

Abstract

The impact fracture energy and stress for the bulk amorphous Zr55Al10Cu30Ni5 alloy were measured by using the Charpy test specimen with U-shape notch. The maximum stress and displacement at the impact fracture are 1615 MPa and 0.44 mm, respectively, and the impact fracture energy is measured to be 63 kJ/m2. The impact fracture stress is nearly the same as the static tensile fracture strength (≒1570 MPa) obtained in a wide strain rate range of 10-4 to 10-1 s-1 for the Zr-based bulk amorphous alloy. The impact fracture energy is higher than those (12 to 36 kJ/m2) for newly developed Al-based high-strength alloys which have been used in some application fields. The fracture surface appearance changes from the vein pattern in the region near the U-shape notch to an equiaxed dimple-like pattern in the inner region. The first evidence of the high impact fracture energy is important for development of the Zr-based bulk amorphous alloy as a new engineering material.