Superconductor's Critical Current at a New High

Abstract

Two new reports made at the high-temperature symposium at the Materials Research Society's fall meeting in Boston concerning the superconductor compound, yttrium-barium-copper oxide ceramic, are presented. One report dealt with a new fabrication technique developed by workers at Bell Laboratories. This new procedure termed melt-textured growth process involves pressing yttrium-barium-copper oxide powders into the desired shape, sintering, and then cooling by a proprietary regimen to bring it back to room temperature. This process produces a material with a much higher critical current than previously reported. The second report dealt with superconductivity at room temperature as measured by workers at Georgia Institute of Technology. The detailed instructions for the preparation of the ceramics with a transition temperature of 500 K and superconductivity at room temperature are reported. These compounds were found to be very moisture-sensitive but were stable for up to 3 weeks in a moisture-free atmosphere.