Thermochemical Stability and Nonstoichiometry of Yttria-stabilized Bismuth Oxide Solid Solutions
نویسندگان
چکیده
The thermochemlcal stablllty of fast oxygen ion conductlng yttria stabillzed blsmuthoxlde (YSB) r solld solutlons containing 22.0 32.5 mol% of yttrla was investigated. It was shown that In the temperature range between 650 740 C the stabilized cublc ~ -phase contalnlng less than 31.8 mol% of yttrla ls not stable durlng long term annealing treatments (>~500 hours). During annealing at 650 C a slugglsh transformatlon from the cubic to hexagonal phase appears, while above 740 C thls hexagonal phase is converted very fast Into the cublc phase agaln. It was shown, that the oxygen content of YSB solld solutions is a functlon of temperature and oxygen partlal pressure.
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