PROCESS FOR PREPARING HIGH-TEMPERATURE SUPERCONDUCTIVE CERAMICS Russian patent published in 1994 - IPC

FIELD: ceramics production. SUBSTANCE: powder of superconducting is filled into a mold, heated in the air to a temperature of T_р-450^°C≅ T≅ T_р-200^°C (in which T_р is the decomposition temperature of barium cuprate), by applying a pressure of 80-300 MPa for 910-940 C maintained isothermally for 1.5-6.0 hr followed by cooling. All the specimens made of yttrium, ytterbium and europium barium cuprates are superconductors having a critical superconducting transition temperature of T_с and a transition temperature range of ΔT_с, respectively. The parameters T_с и ΔT_с concerning the surface and volume parameters of the specimens vary by not greater than 0.3 K. The formal content of oxygen in superconductors is O_6,8-6,95 with the oxygen variations in the volume of specimens within 0.01-0.03%. EFFECT: greater homogeneity of the composition and improved stability of superconducting properties in the volume of ceramics.