Design of a bulk amorphous alloy containing Cu-Zr with simultaneous improvement in glass-forming ability and plasticity

摘要

We synthesized bulk amorphous alloy systems of Cu_(43)Zr_(43)Al_7X_7 (X = Be, Ag; numbers indicate at.%), with the objective of simultaneously enhancing the glass-forming ability (GFA) and the plasticity. The alloys not only exhibit high plasticity (～7%, ～8%), but also possess enhanced GFA (alloys with 12 and 8 mm diameter). The possible mechanisms underlying this enhanced GFA and plasticity exhibited by these alloys are discussed based on the atomic-packing state and atomistic-scale compositional separation associated with the mixing enthalpy difference. A strategy for designing bulk amorphous alloys with simultaneous improvement in the GFA and the plasticity is proposed from the viewpoint of atomic-packing state and atomistic-scale phase separation.