Intergrain and Intragrain Critical Current Densities of Ag-Doped YBa2Cu3O7-y Superconductors

Abstract

The effects of Ag doping on the intergrain and intragrain critical current density properties of YBa2Cu3O7-y superconductors were investigated. As a result of AC inductive measurement and four-probe DC measurement, it becomes clear that both intergrain and intragrain critical current densities are enhanced below 10 wt% Ag. This improvement suggests that Ag particles which precipitated in YBa2Cu3O7-y grains act as pinning centers. At high Ag concentration of more than 15 wt%, intergrain critical current density decreases though the intragrain critical current density is enhanced. The influence of pinning force and grain boundaries is discussed at a macroscopic level.