Magnetic anisotropy in melt-texture grown Y/sub 1/Ba/sub 2/Cu/sub 3/O/sub 7-x/ superconductors

We report on the preparation and characterization of melt textured superconductors with special emphasis on their magnetic anisotropy. The magnetization loops and critical currents obtained for different direction are described. We clearly display that with slower rates of cooling from the partial melt, larger grain growths are obtained even in the absence of temperature gradients. Flux pinning and critical currents are displays larger magnetizations for applied fields parallel to the c-axes that for the field along the ab-plane. The field dependence of the critical currents is highly anisotropic. Exponential, as well as power law type for Jc(H) behavior is obtained, depending on the orientation. The anisotropy of flux pinning and magnetization are discussed both with respect to the variations in preparation techniques and the phenomenological critical state model. (author) 5 figs