In situ Observation of Phase Transformation in MnAl(C) Magnetic Materials
AbstractThe phase transformation in two modes, including both displacive and massive growth of τ-phase from ε-MnAl(C), was observed by in situ transmission electron microscopy. The exact temperature range for different phase transformation modes was determined by magnetic measurements. The displacive growth of ε→τ in Mn54Al46 (or Mn54Al46C2.44) occurs at temperatures below 650 K (or 766 K), above which both modes coexist. One-third or less of the ε-phase can be transformed into τ-phase via displacive mode while the remaining two-thirds or more via massive mode. In bulk τ-phase, most τ-nanocrystals formed via displacive mode are distributed in the matrix of large τ-grains that formed via massive mode. The typical massive growth rate of the τ-phase is 8–60 nm/s, while the displacive growth rate is low. A more complete understanding of the ε→τ phase transformations in the MnAl-based magnets was provided in this work, based on which the annealing process for ε→τ was optimized and thus high purity τ-phase with high saturation magnetization was obtained. View Full-Text
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Si, P.-Z.; Qian, H.-D.; Choi, C.-J.; Park, J.; Han, S.; Ge, H.-L.; Shinde, K.P. In situ Observation of Phase Transformation in MnAl(C) Magnetic Materials. Materials 2017, 10, 1016.
Si P-Z, Qian H-D, Choi C-J, Park J, Han S, Ge H-L, Shinde KP. In situ Observation of Phase Transformation in MnAl(C) Magnetic Materials. Materials. 2017; 10(9):1016.Chicago/Turabian Style
Si, Ping-Zhan; Qian, Hui-Dong; Choi, Chul-Jin; Park, Jihoon; Han, Sangho; Ge, Hong-Liang; Shinde, Kiran P. 2017. "In situ Observation of Phase Transformation in MnAl(C) Magnetic Materials." Materials 10, no. 9: 1016.
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