Ti/Zr-based bulk metallic glass composites (BMGCs) containing an in-situ formed beta phase ((beta-type BMGCs) normally show a poor work-hardening capability or even work-softening during plastic deformation. The limited work-hardening capability of the beta phase by the entanglement of dislocations cannot totally compensate the shear softening of the glassy matrix. In this work, a strategy is proposed to destabilize the beta phase, and the BMGC containing a metastable beta phase (metastable beta-type BMGC) shows improved plasticity and work hardening capability due to the deformation-induced phase transformation from (beta-Ti to alpha"-Ti. The underlying principle for destabilizing beta phases in BMGCs by adjusting the overall compositions and the structural origins for the improved plasticity and work-hardening capability of metastable (beta-type BMGCs are discussed. These findings shed light on developing metastable beta-type BMGCs with excellent mechanical properties.
