Phase Evolution and Glass Formation in an Fe-Based Alloy

Abstract

The understanding of phase competing is of pretty importance in designing high glass-forming systems. In this work, it has been investigated experimentally and theoretically the phase evolution and glass formation of a wedge-casting Fe-based alloy. The results indicated that the phase formation was sensitive to the wedge position, i.e., there were amorphous phase, Fe 2 P, {Fe, Ni} and α-Fe precipitates as well as M 23 B 6 phase at the distances of 3, 10 and 20 mm away from the wedge-tip, respectively. These were closely connected with the variation of cooling rate, embodied in the heat transfer at the solidification process. Furthermore, we constructed the time-temperature-transformation (TTT) diagrams of the iron-based alloy and these crystal phases through calculating R c -related functions. Finally, the glass-forming features of the wedge-shaped Fe-based alloy have been elucidated in accordance with a crystallization kinetics analysis of the recorded temperature data and the phase selection competition. This research provides us an insight into in-depth understanding bulk metallic glass from the perspective of kinetics competition of crystallization phases.