High temperature deformation of VGF melt-textured YBCO

The deformation behavior of melt-textured YBCO prepared by the vertical gradient freeze (VGF) method was investigated by high temperature deformation experiments at temperatures ranging from 850 C to 950 C. The experiments were performed in an atmosphere of pure oxygen under uniaxial pressure with constant strain rates in the range from 1 x 10"-"5 s"-"1 to 5 x 10"-"4 s"-"1. An analysis of the dependence of the steady state flow stress on the strain rate and the deformation temperature reveals that the predominant deformation mechanism is dislocation glide and climb controlled by climb at Y-211 particles and that no significant grain boundary sliding occurs. Furthermore, TEM observations of deformed and undeformed samples support a deformation mechanism based on dislocation movement. The total fracture strain, however, does not depend on the temperature or strain rate. SEM investigations of the fracture faces of samples deformed unti fracture reveal that fracture does not occur within the Y-123 matrix but along platelet boundaries. An improvement of the fracture behavior is expected by introducing large Y-211 particles interconnecting neighboring platelets. (orig.)SIGLEAvailable from TIB Hannover: DtF QN1(67,33) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

Batch production of high-quality-customized-shaped-monolithic HTSC Final report

Customized shaped monolithic YBCO were preduced applying the TSMG method. These HTSC are single-domain monoliths according to optical microscopy, X-ray diffraction, neutron diffraction as well as hall probe measurements. The trapped magnetic induction of such a single-domain monolith at 77 K usually well exceeds 600 mT. An external scan of the remanent induction of a 17 mm x 17 mm x 8 mm large-single-domain sample at 77 K yields a record value of 865 mT. The zfc levitation forces of standard samples (38 mm x 38 mm x 12 mm) at 77 K typically amount to 60-70 N. Actually, 16 units with these standard sizes of the quality described can be produced in one batch. Furthermore, YBCO monoliths with diameters up to 130 mm were successfully melt-textured. (orig.)SIGLEAvailable from TIB Hannover: DtF QN1(67,32) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

Kryobehaelter mit HTSL-Lagerung. Aufbau und Eigenschaften von selbststabilen HTSL-PM Magnetlagern fuer Kryobehaelter

SIGLEAvailable from TIB Hannover: DtF QN1(70,51) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

LH_2-Kryobehaelter mit HTSL-Lagerung des Innentanks

SIGLEAvailable from TIB Hannover: DtF QN1(68,19) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman