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Improved Superconducting Properties in Bulk MgB2 Prepared by High Energy Milling of Mg and B Powder

Y. F. Wu·Y. F. Lu·G. Yan·J. S. Li·Y. Feng·H. P. Tang·S. K. Chen·H. L. Xu·C. S. Li·P. X. Zhang
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Abstract

The MgB2 bulks were prepared by high energy milling of Mg and B powder. The correlations among milling times, microstructure and superconducting properties were investigated in MgB2 bulks. Samples were characterized by x-ray diffraction (XRD), energy dispersive spectrometry (EDX) and scanning electron microscope (SEM), and the magnetization properties were examined by a Superconducting quantum interfere device (SQUID) magnetometer. It showed that the high energy milling is an effective approach to get fine crystalline (40-100nm) bulk MgB2 with good grain connectivity and high Jc performance. The critical current density reaches to 2.0X10E6A/cm2 at 15K and 0.59T, 5.7X10E5A/cm2 at 2T and 3.0X10E4A/cm2 at 5T.

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Y. F. Wu, Y. F. Lu, G. Yan, J. S. Li, Y. Feng, H. P. Tang, S. K. Chen, H. L. Xu, C. S. Li, P. X. Zhang. 2006-07-13. Improved Superconducting Properties in Bulk MgB2 Prepared by High Energy Milling of Mg and B Powder. https://doi.org/10.1088/0953-2048%2F19%2F11%2F021

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