High-temperature superconducting solid bodies and process for producing them

摘要

PCT No. PCT/EP94/02206 Sec. 371 Date Nov. 27, 1995 Sec. 102(e) Date Nov. 27, 1995 PCT Filed Jul. 6, 1994 PCT Pub. No. WO95/02717 PCT Pub. Date Jan. 26, 1995The invention relates to a process for producing textured high-temperature superconducting solid shaped parts, which comprises solid shaped parts made of oxide-ceramic superconducting material of a phase mixture of the substance class YBCO first being molded, pressed and sintered, a zonewise thermal treatment then being carried out along their longitudinal axis. Heating is first carried out, in a first zone, to a temperature in the range of from 50 to 200 K below the peritectic melting temperature of the phase mixture initially present in the shaped part, the temperature then is raised, in a second zone having a temperature gradient in the range of from 10 to 250 K/cm, then, in a third zone, a temperature of up to 50 K above the peritectic melting temperature of the phase mixture initially present in the shaped part is maintained, cooling then being carried out, in a fourth zone having a temperature gradient in the range of from 10 to 250 K/cm. Finally, in yet a fifth zone, a temperature in the range of from 50 to 200 K below the peritectic melting temperature of the phase mixture initially present in the shaped part is maintained. According to the invention, the zones are moved along in the longitudinal direction at a speed in the range of from 1 to 10 mm/h.