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MgCNi 3,an intermetallic compound superconductor with a cubic perovskite crystal structure,has been synthesized using fine Mg and Ni powders and carbon nanotubes (CNTs) as starting materials by the conventional powder metallurgy method.The composition,microstructure and superconductivity are characterized using x-ray diffraction (XRD),energy dispersive x-ray (EDX) analysis,scanning electron microscopy (SEM),and superconducting quantum interference device (SQUID) magnetometer.The results indicate that the phases of the synthesized samples are MgCNi 3 (major phase) and traces of C and MgO.The MgCNi 3 particle sizes range from several hundreds of nanometres to several micrometres.The onset superconducting transition temperature T c of the MgCNi 3 sample is about 7.2 K.The critical current density J c is about 3.44 × 10 4 A/cm 2 calculated according to the Bean model from the magnetization hysteresis loop of the slab MgCNi 3 sample at 5 K and zero applied field.
MgCNi 3, an intermetallic compound superconductor with a cubic perovskite crystal structure, has been synthesized using fine Mg and Ni powders and carbon nanotubes (CNTs) as starting materials by the conventional powder metallurgy method.The composition, microstructure and superconductivity are characterized using x- ray diffraction (XRD), energy dispersive x-ray (EDX) analysis, scanning electron microscopy (SEM), and superconducting quantum interference device (SQUID) magnetometer. The results indicate that the phases of the synthesized samples are MgCNi 3 (major phase) and traces of C and MgO. The MgCNi 3 particle sizes range from several hundreds of nanometres to several micrometres. The onset superconducting transition temperature T c of the MgCNi 3 sample is about 7.2 K. The critical current density J c is about 3.44 × 10 4 A / cm 2 calculated according to the Bean model from the magnetization hysteresis loop of the slab MgCNi 3 sample at 5 K and zero applied field.