粉末套管法制备碳掺杂MgB2线材及其超导电性

Fabrication and Superconducting Properties of MgB_2 Wires with Amorphous Carbon Doping by In-situ Powder-in-tube Method

采用原位粉末套管法制备了无定形碳掺杂MgB2/Nb/Cu超导线材。利用扫描电镜、输运法测试和磁测法等手段分析了无定形碳掺杂对超导线材的微观结构和超导电性的影响。结果表明,无定形碳掺杂降低了线材的临界转变温度,但可以显著提高超导线材的临界磁场和临界电流密度,750℃处理线材在20K下的不可逆场达到5.2T。实验结果表明,采用无定形掺杂原位粉末套管法可以制备出具有高临界电流密度的MgB2线材。

carbon-doped MgB2/Nb/Cu wires were fabricated by in-situ powder-in-tube method. The samples were characterized using scanning electron microscope, standard four probe technique and magnetometer. It is found that amorphous carbon doping decreases the critical temperature of MgB2/Nb/Cu wires but significantly improves the critical field and critical current density. The irreversibility field of the wire sintered at 750℃ reaches 5.2 T at 20 K. The results show a good prospect in fabricating high performance MgB2 wires by in-situ PIT method.