Phase and microstructure evolution of SrCeO3 ceramic when exposed to molten V2O5 at 700–1250 ºC. (December 2018)

• Record Type: Journal Article
• Authors: Yuan, Jieyan; Zhang, Hao; Zhou, Xin; Sun, Junbin; Wang, Jinshuang; Dong, Shujuan; Jiang, Jianing; Deng, Longhui; Cao, Xueqiang
• Is Part Of: Corrosion science. Volume 145(2018)
• Page Start: 295
• Page End: 306
• Publication Date: 2018-12
• Subjects: A. Ceramic -- A. Molten salts -- B. SEM -- C. Hot corrosion; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2018.10.013
• Languages: English
• ISSNs: 0010-938X

Abstract

Graphical abstract: Two stages are involved in SrCeO3 under V2 O5 attack: the first stage involves a dissolve-precipitation process and the subsequent involves a grain boundary attack process with Sr 2+ leaching out from SrCeO3 grains. Highlights: At 700 °C or 900 °C, V2 O5 reacted with SrCeO3 ceramic to form Sr2 V2 O7, CeO2 and CeVO4 . At 1250 °C, the main corrosion products were Sr3 V2 O8 and CeO2 . The corrosion zone comprised of several regions, each with a different composition. The hot corrosion mechanism was explained by phase diagram and lewis acid-base rule. A model describing the formation of the corrosion zone was established. Abstract: Hot corrosion behaviour of SrCeO3 ceramic in molten V2 O5 was studied at 700–1250 °C. Sr2 V2 O7, CeO2 and CeVO4 were the main reaction products at 700 °C and 900 °C, while only Sr3 V2 O8 and CeO2 can be detected at 1250 °C. The corrosion zone was divided into several layers. Both the structure and composition of the corrosion zones were dependent on the corrosion temperature. The microstructure of corrosion zone appeared to have evolved in two major stages, including a first dissolve-precipitation process and a subsequent grain boundary attack process. Finally, a model describing the formation of the corrosion layer was established.