High-T/sub c/ superconducting magnets that function at liquid oxygen temperature

This article reports on a superconducting material suitable for a superconducting magnet that can function up to liquid oxygen temperature (90.2 K). This achievement provides a distinguished step toward industrial applications of liquid oxygen, which is as broad as those of liquid nitrogen. The strong flux pinning at 90.2 K was recently achieved in a (Nd/sub 0.33/Eu/sub 0.33/Gd/sub 0.33/)Ba/sub 2/Cu/sub 3/O/sub y/ compound in that nanometer size Zr-based pinning centers are distributed. This composite exhibited at 90.2 K an outstanding critical current density > 40 kA/cm/sup 2/ that fulfils the requirements of some industrial applications.