Design ductile and work-hardenable composites with all brittle constituents

Metallic glasses, like many other glasses and ceramics, generally have zero tensile ductility. Distinct from common wisdom which seeks to toughen brittle with ductile phases, we show that composites made two can be ductile, strong even harden under tension as a result of microstructure stiffness contrast. Using molecular dynamics simulations, designed tested consisting alternating wavy nanofilaments different stiffness. The exhibit failure strain over 40% hardening modulus 2 GPa. ductility is determined by both the flexibility propensity crack deflection, composite design map constructed. due filament alignment analogous linear polymer. brittle-brittle strategy proposed here not material-specific should applicable to, for instance, ultra-hard materials constituents in achieving new damage-resistance composites.