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Highlights • A new Ti-based BMGC with the composition of Ti 57.3 Zr 19.6 Cu 4.7 Ni 2.8 Be 12 Nb 3.6 was developed. • The composite shows large homogeneous ductility and significant work-hardening capacity. • The toughening mechanism is a combined effect of stress-induced martensitic transformation and mechanical twinning. Abstract A new Ti-based BMGC with excellent tensile plasticity and significant work-hardening capacity was successfully developed. The microstructure, mechanical behaviors and toughening mechanisms were investigated in details by SEM, XRD, TEM and Nano-indentation. It is found that the stress-induced martensitic transformation from β to α″ phase and the mechanical twinning in the α″ phase combined to account for these mechanical behaviors. The current work offers a new perspective for developing in situ dendrite reinforced BMGCs with improved homogeneous ductility and significant work-hardening capacity. [ABSTRACT FROM AUTHOR]

A novel series of in - situ dendrite Ti-based bulk metallic glass composites (BMGCs) were obtained. The Mo content of the dendrites monotonically increases from nil to 10.5 at% while the dendrite volume fraction and the composition of the amorphous matrix remain nearly invariant. It was found that the mechanical behaviors varied tremendously simply by changing the Mo content. Thus, the correlation between the composition and the mechanical behaviors under tension has been determined for in - situ dendrite Ti-based BMGCs for the first time. [ABSTRACT FROM AUTHOR]

Lightweight materials with good combinations of properties, such as high strength, ductility and damage tolerance, are highly desirable in engineering applications; nevertheless, it remains a challenge to "defeat" the generally exclusive relationships between different properties for structural materials. One viable means is to construct complicated architectures in materials. Here, we employ a lightweight Ti-based metallic glass (MG) and pure Ti as constituents and assemble them into a hierarchically-structured multiphase composite with tailored heterogeneity. The Ti-rich multiphase composite exhibits a relatively low density of 4.95 g ∙ c m − 3 owing to its high Ti content and a high strength of ∼1408 MPa derived primarily from the MG phase. The hierarchical architecture with tailored heterogeneity promotes the formation of abundant shear bands and microcracks in MG, yet inhibits their extension to avoid catastrophic fracture, thereby endowing the Ti-rich multiphase composite with a remarkable tensile ductility of ∼7.1% which is nearly two times that of the MG composite having similar phase constitution but a uniform structure. Moreover, this architecture causes crack-tip blunting by promoting plastic deformation, together with crack bifurcation and microcracking ahead of the crack tip, which bestows a high (notched) fracture toughness of ∼109 M P a ∙ m 1 / 2 which is around three times that of its counterpart. This study is intended to give insight for the architectural design of new materials by offering a viable means for their architectural construction to achieve good combinations of properties. [ABSTRACT FROM AUTHOR]