Microstructure formation and magnetocaloric effect of the Fe2P-type phase in (Mn,Fe)2(P, Si, B) alloys

作者：Lai, J. W.; Zheng, Z. G.^*; Huang, B. W.; Yu, H. Y.; Qiu, Z. G.; Mao, Y. L.; Zhang, S.; Xiao, F. M.; Zeng, D. C.^*; Goubitz, K.; Bruck, E.

来源：Journal of Alloys and Compounds, 2018, 735: 2567-2573.

DOI：10.1016/j.jallcom.2017.11.287

• (Mn,Fe)(2)(P, Si, B)
• Magnetocaloric
• Microstructure formation
• Magnetic properties
• Entropy

The relation between the microstructure and the magnetic properties of Fe2P-type (Mn,Fe)(2)(P,Si,B) based materials has been systematically investigated by changing the annealing temperature and time. X-ray diffraction, Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy measurements show that the alloys contain the main Fe2P-type phase and two impurity phases of (Fe,Mn)(5)Si-3-type and Fe2MnSi-type. Boron appears to facilitate the formation of the Fe2P-type phase during the arc-melting progress. Upon increasing the annealing temperatures from 1123 to 1423 K, the Curie temperature (T-C) decreases from 302.0 to 270.5 K in the Mn1.15Fe0.85P0.55Si0.45 alloys and the magnetic-entropy change (Delta S-M) increases linearly with annealing temperature. For the Mn1.15Fe0.85P0.52Si0.45B0.03 alloys annealed at 1423 K for different times, TC decreases from 263.8 and 232.8 K with increasing annealing time and Delta S-M reaches a maximum value after annealing for 48 h. The differences in the annealing temperature and time influence the Si content in the Fe2P-type phase of the alloys and determine T-C, the thermal hysteresis and the magneto-elastic transition.

• 出版日期2018-2-25
• 单位华南理工大学