Improved Superconducting Properties in Bulk MgB2 Prepared by High Energy Milling of Mg and B Powder
نویسندگان
چکیده
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 2.0× 10A/cm at 15K and 0.59T, 5.7× 10A/cm at 2T and 3.0× 10A/cm at 5T. PACS numbers: 74.70.Ad, 74.62.Bf, 74.25.Qt, 74.25.Sv, 74.50.+r, 74.70.-b † To whom correspondence should be addressed ([email protected]) Improved Superconducting Properties in Bulk MgB2 Prepared by High Energy Milling of Mg and B Powder2
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