Temperature dependency of viscosity of Fe76Si9B10P5 supercooled liquid and hetero-amorphous structure

In this study, we evaluated the thermal stability and fragility of Fe76Si9B10P5 supercooled liquid by using micrometer-scale particles prepared via a container-less solidification process. After construction of time-temperature-transformation (TTT) diagram of crystallization by means of isothermal DSC under various temperatures, we could successfully measure the viscosity of the particles in the supercooled liquid region by employing the single particle compressive test (SPCT). It is revealed that the temperature dependency of viscosity cannot be well fitted by the Vogel-Fulcher-Tammann (VFT) formula but can be fitted by an Arrhenius plot. The Angell plot indicates that the apparent fragility is higher than that of SiO2 and the fabricated particles have hetero-amorphous structures composed of high-density nanoscale clusters dispersed uniformly in a glassy matrix phase.