YBa2Cu3O7-xpowders, made at Argonne National Laboratory by solid-state reaction or supplied by Rhone-Poulenc, were sintered in oxygen at 910 or 950 degrees C. Heating rates to the sintering temperature were varied from 0.5 to 5 degrees C min-1. Sintered specimens were characterised by differential thermal analysis, X-ray diffraction, optical and scanning electron microscopy, and measurement of electrical resistivity, superconducting transition temperature and critical current density. It was found that the heating rate affected only the properties of specimens which were heated to a temperature at which second phases present could react. Slower heating improved electrical properties as a consequence of inducing greater reaction to desired phases such as YBa2Cu3O7-x.
All Science Journal Classification (ASJC) codes
- Ceramics and Composites
- Condensed Matter Physics
- Metals and Alloys
- Electrical and Electronic Engineering
- Materials Chemistry