Microstructure change and deuterium permeation behavior of erbium oxide coating

Deuterium permeation measurements and microstructure analyses on erbium oxide coating deposited by filtered arc deposition have been investigated. It is found that the permeation suppression efficiency is proportional to the coating thickness in case of the coating without pores and cracks reaching to the substrate. A phase transformation of the coating during the permeation measurements at 773–973 K has been identified. A grain growth of the coating has occurred during the measurements and permeation suppression efficiency have enhanced according to the grain size. It is suggested that deuterium permeation through the coating is mainly dominated by the crystal grain diffusion.