Tensile Mechanical Behaviors of In Situ Metallic Glass Matrix Composites at Ambient Temperature and in Supercooled Liquid Region

Abstract

In this study, new Ti-based metallic glass matrix composites (MGMCs) are fabricated, which contains ~41 vol pct of large dendrites with a size of ~0.8 to 1.2 μm, The newly developed Ti-based MGMCs exhibit excellent tensile strength of ~1650 MPa and a tensile strain of ~2.5 pct at room temperature. During tensile deformation, the work hardening is scarcely found in this alloy. Thus, the deformation of the in situ MGMC is simply described with two stages: (1) elastic and (2) softening deformation stages. Two simple models are adapted to simulate each stage. In the supercooled liquid region [at 613 K (340 °C)], superplastic homogeneous deformation, which is the feature of monolithic bulk metallic glasses, is not observed. The mechanical properties at 613 K (340 °C) are sensitive to the strain rates, the yield strength drops from 1390 to 960 MPa, when the strain rate decreases from 1 × 10−2 to 1 × 10−3/s, while the displacement is almost increased by twofold.