Permeation Characteristics of YSZ Films During the Deposition on a Porous NiO/YSZ Substrate

Abstract

Films of YSZ have been deposited on a porous NiO/YSZ substrate by a slurry coating method. Evolution of gas permeation rate through the film during the deposition was measured at 600--1,000 C using He, N{sub 2}, Ar and O{sub 2}. The viscous flow effect dominated the gas permeation through the porous NiO/YSZ substrate. As the YSZ layer was formed on the substrate, however, the gas permeation rate decreased and the permeation through the YSZ films became governed by Knudsen diffusion. The permeation rate through the porous YSZ films decreased with increasing temperature. As the film became denser, YSZ film became selective for O{sub 2} permeation. The permeation rate of O{sub 2} through the dense YSZ film increased with increasing temperature.