Electrical Properties Correlated to the Chemical and Granular Microstructures in YBaCuO Ceramics

Abstract

Two types of correlations between the superconducting properties and the microstructures in YBaCuO ceramics prepared by the freeze‐drying method are studied. The first one is a correlation between the critical current density Jc in zero magnetic field, the diamagnetic effect, and the anisotropy of the crystal growth. It is observed that the more the crystal growth is isotropic, the larger is the critical current at 77 K. The second one is a correlation between Jc and the chemical microstructure supported by numerous X‐ray microanalyses which show that Jc is statistically strongly dependent on the couple concentration—distribution of the CuO residual phase.