Inter- and Intra-granular Critical Current in Bi1.4Pb0.6Sr2Ca2Cu3.6Ox Superconducting Oxide

摘要

A.c. susceptibility for Bi1.4Pb0.6Sr2Ca2Cu3.6Ox superconductor is measured as a function of temperature at different value of a.c. magnetic field amplitude. Two transition steps are attributed to the intergranular and intragranular properties. Based on Bean`s critical state model, intergranular critical current density, Jcgb (11 A/cm2 at 77 K) and intragranular critical current density, Jcg (7】103 A/cm2 at 100 K) are estimated. The low values of Jcgb and Jcg reflect a poor nature of coupling between grains and the low pinning force density of intragrain in Bi1.4Pb0.6Sr2Ca2Cu3.6Ox superconductor.