The process of Zn diffusion in YBa2Cu3O7–x ceramics with a porosity of 20–30% was studied from 110 to 450C by using a 65Zn radioactive tracer. The temperature dependence of the tracer diffusion coefficient could be described by:

D (cm2/s) = 5 x 10-9 exp[-0.25(eV)/kT]

It was concluded that Zn migrates predominantly via pores and intergranular layers in the ceramics.

Zinc Diffusion in YBa2Cu3O7–x Ceramics. G.S.Kulikov, R.S.Malkovich, E.A.Skoryatina, V.P.Usacheva: Technical Physics Letters, 2002, 28[5], 427-9