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内容記述 |
In this study, corrosion behavior of F82H reduced activation ferritic/martensitic steel (RAFM) by LTZO (Li2+xTiO3+y solid solution with 20?wt% Li2ZrO3) ceramic breeder pebbles was investigated at 773?998?K in an inert sweep gas condition (Ar?+?0.1?% H2). Due to vapor gas release from the breeder pebbles and those penetrations, corrosion layer formed on the surface of the F82H steel. Glow discharge optical emission spectroscopy (GD-OES) and X-ray diffraction (XRD) identified the corrosion products as cubic, spinel, and rhombohedral Li?TM?O (TM: transition element in F82H such as Fe, Cr, and Mn). The growth of the corrosion layer thickness followed a parabolic curve at 833?K, yielding apparent diffusion coefficient of D = 6.95?×?10?13 cm2/s. Rapid growth was observed at 993?K after a parabolic growth which could be triggered by failure of the protective layer. A comparative analysis indicates a predominant effect of humidity and oxygen in the sweep gas on the growth rate, while the composition and shape of breeding materials have minor impacts. |
