Superconducting Properties and Oxygen Diffusion of Hot-pressed YBa₂Cu₃O_x Ceramics

Abstract

We have studied that the characteristics of YBa₂Cu₃O_x superconducting ceramics with hot-pressed in air and oxygen atmosphere was affected by the oxygen diffusion. In the hot-pressed samples in air, since absorbed about 40% oxygen compare that a ordinary sintered methods, it's structure indicated either the tetragonal or the orthorhombic close to tetragonal, besides superconducting did not show until near 77K in spite densification. While the hot-pressed samples in 2-3atm. of oxygen with adding 1-10wt% Ag₂O not only indicated the orthorhombic phase but also showed superconducting at 91K regardless of densification, since it was to promote a high oxygen content within material during a sintering process. Therefore we believed that a superconducting and crystal structure of sample was affected by sensitive changes in oxygen content.