Excellent glass forming ability and plasticity in high entropy Zr20Ti20Hf20M20Be20 (M = Cu, Ni, Co) alloys

Abstract

We reported here the studies of a series of Zr20Ti20Hf20M20Be20 (M = Cu, Ni and Co) quinary high entropy bulk metallic glasses. Glasses with critical diameters (Dc) of 3 mm, 8 mm and 5 mm, respectively has been successfully fabricated by copper mold casting. Strikingly, a plastic strain of 11.6% is achieved in the Zr20Ti20Hf20Cu20Be20 metallic glass. The dynamic fragility the Zr20Ti20Hf20Cu20Be20 alloy is determined from calorimetric measurements. The excellent plasticity is explained to be attributed to relatively higher fragility. Keywords: High entropy alloys, Bulk metallic glasses, Glass forming ability, Mechanical property and fragility