A new Cu–Hf–Al ternary bulk metallic glass with high glass forming ability and ductility

We have discovered a new Cu-based bulk metallic glass (BMG). Although of a simple Cu49Hf42Al9 ternary composition, the as-cast alloy is a monolithic, uniform BMG with a critical diameter as large as 10 mm. The width of the supercooled liquid region ΔTx and the reduced glass transition temperature Trg for this glass are 85 K and 0.62, respectively. In addition to its high glass-forming ability and high density of ∼11 g/cc, this BMG exhibits high ductility with a compressive plastic strain of 11–13%, making it a good candidate for applications as well as for studies of deformation behavior of Cu-based BMGs.