Transient creep of YBa2Cu3O7-x superconductor

Rapid changes of oxygen partial pressure (P-O2) between 10(3) and 2.1 X 10( 4) Pa have been carried out during steady-state plastic deformation of poly crystalline YBa2Cu3O7-x (YBCO) at temperatures between 825 and 900 degrees C. Transient creep was observed after such P-O2 changes. The analysis of th ese creep transients allowed the determination of the chemical diffusion co efficient for reequilibration, which is identical to that found from thermo gravimetry and electrical conductivity experiments for oxygen vacancies. (C ) 1999 Elsevier Science B.V. All rights reserved.