Routes to obtain high performance, high T-c superconducting bulk materials

This paper reviews our investigations for understanding the fundamental rel ations between physical properties, crystal chemistry, phases relation and processings on the compounds YBa2Cu3O7-x and Bi(Pb)(2)Sr2Ca2Cu3O10+x. These two systems have in common the complexity of their crystal structure and m ulti-components chemistry which require challenging material processing for applications. In the YBaCuO system, horizontal bridgman and melting zone p rocesses have demonstrated the possibility of obtaining high performances i n this system, with different shaping. A high reproducibility with low mate rial losses have been achieved with a top seeding melt texturing process. F or BiSSCO based compounds, sol-gel and polymer matrix methods have been stu died and developed with the achievement of promising critical current densi ties at 77 K. (C) 2000 Elsevier Science Ltd. All rights reserved.