METHOD FOR PRODUCING LONG HIGH-TEMPERATURE WIRES Russian patent published in 2000 - IPC

FIELD: superconducting engineering for electrical pieces of equipment. SUBSTANCE: method used for producing long composite stranded wires is characterized in that metal tube is filled with ceramic powder of superconducting compound or half-finished product considering that end fill factor of stranded wire is to be 15-50%; tube-and-powder system is deformed by drawing in roller-type reducing dies at 1-5% degree of deformation per pass; composite blank is shaped by fitting sheath of desired lengths of tube-and-powder system being deformed in metal blank alternately with silver-band spacers so as to obtain fill factor of 15-50% for stranded wire; it is deformed by drawing in roller-type reducing dies at deformation degree of 0.5-5% per pass and annealed at 500-700 C for 0.5- 5 h followed by deforming composite blank to desired size by drawing in roller-type reducing dies at deformation degree of 1-30% per pass and performing single-stage heat treatment at 800-850 C until desired superconducting phase is formed; metal blank of sheath is rectangular- or U-section bar covered with tape. Method provides for 5-15%-fold increase in critical current density and for reducing critical bending radius of wire by two to six times. EFFECT: simplified procedure. 3 cl