Thermal Stability and the Matrix Induced Brittleness in a Ti-based Bulk Metallic Glass Composite

Crystallization kinetics and nanocrystalline induced brittleness in an in-situ dendrites reinforced Ti₄₄Zr₂₀Nb₁₂Cu₅Be₁₉ bulk metallic glass (BMG) composites were investigated. The activated energy of the present Ti-based metallic glass matrix is obtained to be about 201 KJ/mol. As the annealing temperature rises, the annihilation of free volume is believed to cause the increase of hardness and the decrease of plasticity. Brittle fracture occurs after the precipitation of nanocrystalline, which can be ascribed to the formation of the microcracks in the matrix during deformation.

Keywords:
bulk metallic glass; composite; thermal stability; mechanical properties