IDENTIFYING AND INVESTIGATING J[sub c] VARIATIONS IN COATED CONDUCTORS FABRICATED BY MOCVD∕IBAD

A single‐pass position dependent critical current ${\mathrm{I}}_{\mathrm{c}}$ measurement is described that characterizes the pinning properties of long coated conductor tapes using magnetic fields applied bi‐axially to the conductor. By this method, a 10 meter long MOCVD/IBAD conductor is shown to exhibit position‐dependent variations in the ${\mathrm{I}}_{\mathrm{c}}(\mathrm{H}\Vert \mathrm{ab}\mathrm{)/}{\mathrm{I}}_{\mathrm{c}}(\mathrm{H}\Vert \mathrm{c})$ ratio resulting from underlying variations in the microstructure. Regions with these variations were investigated nondestructively using angular anisotropy and c‐axis magnetic field measurements at 75 K. Results from analytical microscopy confirmed the presence of variations in rare earth oxide precipitate concentrations as a function of position that are attributed to be the cause of the pinning variations.