MECHANICAL ALIGNMENT OF THE GRAINS OF SINTERED YBACUO

It is shown that the combination of deformation and sintering gives ri se to a pronounced alignment of the grains of high T(c) 123 supercondu cting ceramics. The procedure (we call it creep sintering), was thorou gly optimized varying the numerous parameters of the temperature and l oad run one at a time . As a result of a detailed microstructural char acterization, it is concluded that several mechanisms interfer to buil d up the texture, the relative importance of them depends on the tempe rature and the deformation. In addition, it is shown that starting fro m a J(c) of 150 A/cm2 at 77 K for the untextured material , the proced ure allowed to reach 650 A/cm . Moreover adding 2.5 wt% of Pb substitu ted Bi 2223 in order to modify the properties of the liquid phase pres ent during creep sintering, we have increased further the J(c) of the material up to 1010 A/cm2 at 77k and 1950 A/cm2 at 63 K .