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Journal of Shanghai University >

2016 , Vol. 22 >Issue 6: 710 - 718

DOI: https://doi.org/10.3969/j.issn.1007-2861.2015.04.002

Precipitation and growth of Nd2Fe14B/α-Fe during amorphous crystallized process and its magnetic properties

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  • 1. School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China;
    2. School of Materials Science and Engineering, Shanghai University of Engineering Science, Shanghai 201620, China

Received date: 2015-09-01

  Online published: 2016-12-30

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Abstract

The crystal structure, magnetic properties of the Nd9.5Fe76Co5Ti3B6.5  amorphous alloys annealed at different temperatures were investigated by X-ray diffraction(XRD), vibrating sample magnetometer (VSM), and differential scanning calorimeter (DSC). The results indicated that the Nd2Fe14B phase was precipitated prior to that of α-Fe phase from the amorphous matrix. Nd2Fe14B phase and α-Fe phase were precipitated at 600 and 680 ℃, respectively. α-Fe phase grain growed up more obviously than Nd2Fe14B phase with increasing annealing temperature. The grain sizes of α-Fe phase and Nd2Fe14B phase growed from 22.4 and 32.8 nm to 33.3 and 39.8 nm when they annealed at 690 to 700 ℃. When annealing at 690 ℃, there were strong exchange coupling effects between hard magnetic phase Nd2Fe14B with 32.8 nm and soft magnetic phase α-Fe with 22.4 nm. MeanwhileNd9.5Fe76Co5Ti3B6.5 alloy obtained the best magnetic properties with Br =0.88 T, Hci =523.76 kA/m, and (BH)max=100.01 kJ/m3.

Key words：  exchange coupling;  magnetic property;  nanocomposites;  NdFeB; crystallization

Cite this article

XUE Yun1, HOU Xueling1, HAN Ning2, LU Qianqian1, XU Hui1 . Precipitation and growth of Nd2Fe14B/α-Fe during amorphous crystallized process and its magnetic properties[J]. Journal of Shanghai University, 2016 , 22(6) : 710 -718 . DOI: 10.3969/j.issn.1007-2861.2015.04.002

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