TRACER DIFFUSION OF AG-110 IN YBA2CU3O7-DELTA

Tracer diffusion of 110Ag in YBa 2Cu3O7-δ has been measured in the temperature range 800-950 °C using serial sectioning. The polycrystalline samples were made either from a powder containing about 0.2% Zr prepared by a conventional technique, or from a purer powder that had been calcined in low-pressure oxygen. Concentration profiles indicate both a volume and a fast diffusivity path contribution to diffusion. The activation energies were 227±3 and 249±17 kJ/mole for samples made from powder calcined in low-pressure oxygen and conventional powder, respectively. Diffusion was slower in the samples made from the purer powder.