Bulk YBCO high- superconductors with uniform and full oxygen content via microwave processing

The potential for the use of microwave radiation as an alternative energy source for the sintering and annealing of bulk, ceramic high- YBCO superconductors has been investigated with a view to taking advantage of the opportunities presented by this novel heating technique. Microwave heating has been found to offer the possibility of sintering `from the inside out' due to the nature of the temperature profile developed. As a result, ceramic YBCO bodies measuring 35 mm in diameter by 5 mm thick have been produced with completely uniform and high oxygen content (x = 7 in ) and densities up to 98% of theoretical. These properties were achieved using total processing times approximately one sixth of those required conventionally. A model for the microwave heating process is proposed.