Ti-based metallic glass composites containing β-Ti dendrites

Abstract

Metallic glass composites (MGCs), which consist of crystalline phases embedded within the amorphous matrix, exhibit an excellent strength-ductility combination, compared to the brittle failure of monolithic bulk metallic glasses (BMGs) under uniaxial tension. Owing to the large forming size as well as the good microstructural controllability and repeatability, Ti-based MGCs containing β-Ti dendrites attracted intense research interest in the past years. The critical casting diameters of Ti-based MGCs depend on the glass-forming ability of the glass matrices, which were revealed to be over 50 mm, as ones of the reported-largest BMGs and MGCs. The thermodynamic and kinetic principles along with the techniques underlying the good microstructural controllability of Ti-based MGCs have been explored in-depth. Furthermore, the phase stability of β-Ti dendrites can be largely tuned, and various deformation mechanisms, including dislocation gliding, twining and phase transformations, can be incorporated into Ti-based MGCs, significantly deepening the understanding of cooperative deformation of the glass-crystal dual-phase alloys. Ti-based MGCs possess high strength, high tensile ductility with strain-hardening capability, high toughness and large sizes, which render them promising for wide application as structural engineering materials. The aim of the present work is to provide a comprehensive review on the recent progress of Ti-based MGCs.