Size effects on the superconducting properties of polycrystalline aggregates of Ba sub 2 YCuO sub (7-delta) cuprates.
01 January 1988
A. C. magnetic susceptibility measurements have been performed on polycrystalline aggregates Ba sub 2 YCu sub (7-delta) superconducting cuprates ranging in size from 40micron diameter granules to 3mm x 3mm x 5mm bulk pieces. The susceptibility transition near 90K broadens and becomes progressively shallower for the smaller size aggregates. The phenomenon has been used to follow the consolidation of small aggregates during sintering between 450-950C in an oxygen atmosphere. Significant consolidation occurs at and above 850C allowing the possibility of sintering at somewhat lower temperatures than previously anticipated. The influence of atmospheric moisture appears to be minimal.