抄録
MgB2, which is a new superconducting material with a relatively high temperature superconducting transition, was fully densified by a spark plasma sintering (SPS) technique. The SPS process of the MgB2 was typically performed in the temperature range from 850 to 1200 °C under 50 MPa in an Ar atmosphere. The sintered MgB2 bodies were characterized by a XRD for phase analysis and a SEM and a TEM for microstructural features including the defects such as dislocation structure and secondary phase particles. Their superconducting properties were evaluated by measuring the dc magnetic susceptibility and magnetization hysteresis using a SQUID magnetometer. Also for the enhancement of the flux pinning, the chemically doped MgB2 was applied to the SPS process and the effects of doping elements on phase compositions, microstructure and flux pinning behavior were investigated.
