| 摘要 |
PURPOSE:To increase critical current density by melting a Bi-contg. oxide superconducting material, rapidly cooling the molten material to a temp. at which a superconducting phase is formed and carrying out heat treatment at the temp. CONSTITUTION:Powders of Bi2O3, PbO, SrCO3, CaCO3 and CuO are mixed, calcined at about 800 deg.C for about 12hr in the air, pelletized and sintered at about 835 deg.C for about 48hr. The resulting sintered material is melted at 1,050-1,200 deg.C for 30-60min, rapidly cooled to 830-850 deg.C at >=350 deg.C/min cooling rate and heat-treated at 830-850 deg.C for 12-48hr to obtain a Bi-based oxide superconductor having such a high critical current density as 10<4>-10<5>A/cm<2>. The oxide may be Bi1.84Pb0.34Sr1.91Ca2.13Cu3.06Oy. |
