T1系单相超导材料的高氧压合成及压力对超导性的影响

 系统地研究了在0~3 MPa氧压下T1系超导材料的制备过程及其超导性质。结果表明：0.25~0.90 MPa氧压下所制备的样品为纯2223相，T_c0最高可达125.3 K；1.45~3.00 MPa氧压下样品为纯2212相，T_c0在95~100 K之间；0.90~1.45 MPa氧压下样品为2223及2212两相共存。对两种单相样品的高压研究结果表明，2223相样品比2212相样品有着较强的压力效应，在0~0.52 GPa压力下分别为4.0 K/GPa及2.0 K/GPa。

SYNTHESIS OF Tl-SYSTEM MONOPHASE SUPERCONDUC-TORS UNDER OXYGEN PRESSURE AND IT'S HIGH PRESSURE EFFECT

Effect of oxygen pressure on the preparation of TI-system superconductors at pressure 0～3 MPa is reported. Under the same sintering temperature and in the same duration, the phase fractions and T_c as well as the weight loss are found to depend directly on the oxygen pressure. When the oxygen pressure is higher than 1.45 MPa, we can get pure 2212 phase super conductors. The samples contain both 2212 and 2223 phase if the oxygen pressure is 0.9～1.45 MPa. Pure 2223 phase samples can be obtained when the oxygen pressure is 0.25～0.9 MPa. The high pressure effect on samples with 2223 phase and 2212 phase also was studied. The dT_c0/dp for sample with 2223 phase is 4 K/GPa, and 2 K/GPa for sample with 2212 phase under pressure 0～0.52 GPa. The sample with 2223 phase has stronger pressure effect than their sample with 2212 phase.