Individual grain boundary properties and overall performance of metal-organic-deposition coated conductors

Abstract

We have investigated single grain boundaries (GBs) isolated in coated conductors produced by Metal-Organic Deposition (MOD). When a magnetic field is swept in the film plane, an angle-dependent crossover from boundary to grain limited critical current density Jc is found. In the force-free orientation, even at fields as high as 8 T, the GBs still limit Jc. We deduce that this effect is a direct consequence of GB meandering. We have employed these single GB results to explain the dependence of Jc of polycrystalline tracks on their width: in-plane measurements become flatter as the tracks are narrowed down. This result is consistent with the stronger GB limitation at field configurations close to force-free found from the isolated boundaries. Our study shows that for certain geometries even at high fields the effect of GBs cannot be neglected.

References in corpus (7)

• The critical current of YBa2Cu3O7-d Low Angle Grain Boundaries
• Neutron irradiation of coated conductors
• Vortex Channeling and the V-I Characteristic of YBa2Cu3O7 Low Angle Grain Boundaries
• Practical vortex diodes from pinning enhanced YBa2Cu3O7-d
• Suppression of vortex channeling in meandered YBa2Cu3O7-d grain boundaries
• Benefits of current percolation in superconducting coated conductors
• Enhanced current flow through meandering and tilted grain boundaries in YBCO films