[en] AC susceptibility ; high-Tc superconductors ; critical current
[en] We measured the AC susceptibility of magnetically textured (123) 80%/211(20%) DyBaCuO composite in a special set-up in order to enhance the intergrain contribution. The synthesis process led to very clean ''weak links'' at grain boundaries. At the percolation threshold bulk shielding paths were such that the intergrain critical current density J(c) was above 10(5) A/cm(2). The field dependence of J(c) was understood through an analytical form indicating a distribution of currents similar to the law of clusters at fracture/percolation thresholds.
Services Universitaires Pour la Recherche et les Applications Technologiques de Matériaux Électro-Céramiques, Composites, Supraconducteurs - SUPRATECS
Fonds de la Recherche Scientifique (Communauté française de Belgique) - F.R.S.-FNRS ; Communauté française de Belgique - CfB ; Services Fédéraux des Affaires Scientifiques, Techniques et Culturelles - SSTC