Microstructures and Superconducting Properties of Y-Ba-Cu Oxide Coils Prepared by the Explosive Compaction Technique

Abstract

Explosive compaction technique possesses considerable potential as a means of densifying metal, ceramics and mixtures of these powders. We applied this technique to preparation of silver sheathed coils of Y-Ba-Cu superconducting oxide. The coils to be compacted were placed into metal tube and the tube was filled with SiC powder as a pressure propagating medium and the tube was explosively compacted by a cylindrically axi-symmetric method. The coils explosively compacted were then sintered, and microstructure observations and superconducting property measurements were made. The oxide core was seen to be very dense, and a part of a Y-Ba-Cu oxide coil had a critical current density higher than 13,000A/cm² at 77K. This results show that the explosive compaction technique will be an effective means to prepare coils with excellent superconducting properties.