Intrinsic Tensile Ductility in High Entropy Metallic Glass

Metallic glasses are an important material with a wide range of applications, such as in bio-medical engineering, aerospace engineering, automotive industries, micro-electro-mechanical systems and consumer products. Nevertheless, the Achille’s heel of metallic glasses is short of tensile ductility at low temperature, which impedes their widespread applications as yet. To overcome this limitation, people have proposed different methods to toughen metallic glasses, including surface mechanical attrition treatment, architectured constructions, and deformation induced rejuvenation. Although these methods have shown potential for improving tensile ductility at room temperature, the reported results of intrinsic tensile ductility tend to be limited (< 1%) with a low strain hardening rate. In this work,Here we present a high-entropy metallic glass with unique multifunctional properties. This glass demonstrates exhibits a gigapascal yield strength of ~1.5 GPa, undergoes significant strain hardening that almost doubles its yield strength (~70% strength increase), and exhibits unprecedentedover two-fold increase in uniform tensile ductility compared to the previous records (~ 2%). These remarkable properties stem from the amorphous structure of our high-entropy metallic glass, which is composed of atoms with significant size mismatch. The shear banding in this HEMG is self-locked because of shear induced atomic diffusion. Our findings suggest a promising pathway to design stronger, more ductile glasses that can be applied in a wide range of technological fields.