Simultaneous inductive determination of grain and intergrain critical current densities of YBa2Cu3O7-x coated conductors

An inductive methodology simultaneously enabling the determination of grain- and intergrain critical current densities of YBa2Cu3O7-x coated conductors is developed. This noninvasive method is based on the identification of a clear peak in the reverse branch of the magnetization loop at a positive magnetic field, as a signature of the electromagnetic granularity inherent to these materials. A quantitative evaluation of the return magnetic field at the grain boundaries allows us to understand the existence of this magnetization peak and quantify the grain critical current density. This methodology is envisaged to sort out granularity effects from vortex pinning effects on coated conductors. (C) 2004 American Institute of Physics.