Superconductive YBa2Cu3O7−x fibres from an extrudable dispersion of a particulate precursor

A particulate precursor of YBa2Cu3O7−x was dispersed in a concentrated acetic/formic acid solution of yttrium, barium and copper acetates to form an extensible, viscous mixture. This dispersion was stable, unlike one prepared from superconductive YBa2Cu3O7−x itself. Fibres extruded from the viscous dispersion were fired at 935 °C in the presence of oxygen.