Microstructure modulation and mechanical properties of multicomponent Fe50Cr14Mo14C9B8Tm5 bulk metallic glass through controlled crystallization processing

Fe50Cr14Mo14C9B8Tm5 bulk metallic glass was prepared at a cooling rate of 6.36 × 104 K s−1. Its Young's modulus and compressive strength were modulated through controlled crystallization processing. A low cooling rate induced the formation of the Tm2Mo2C3 phase while preserving free volume. Thus, the elastic deformation limit was increased to 2.39%. After low-temperature annealing, the (Fe, Cr)23(C, B)6 phase was formed at first. As the annealing temperature increased, four types of crystalline phases appeared as dispersions in this alloy, where the hardness of the Fe3Mo3C phase reached 32.5 GPa. Even when the annealing temperature reached 1260 K, the average grain size was only 180 nm. The large volume fraction of the Fe3Mo3C phase and uniform microstructure of crystallized alloy resulted in a high strength of 4.01 GPa and a low Young's modulus of 237.11 GPa.