Toughness and thermal shock resistance of melt-textured YBaCuO ceramic superconductors

摘要

High-T_c YBaCuO ceramic superconductors have been fabricated by the "melt-textured-growth" method. Composite microstructures have been obtained by the adjunction of "211" and silver particles. The toughness has been measured by the indentation technique, and the thermal shock resistance has been investigated by a recently developped method, using the stage of stable extension of Vickers indentation cracks. The presence of silver improves the toughness more than the "211" phase does, and the latter decreases the thermal shock resistance of the material.