オーステナイト鋼の炭化物析出と粒界近傍のクロム濃度変化

抄録

Although many of the phenomena associated with the intercrystalline corrosion of austenitic stainless or heat resisting steels depending on the precipitation of carbides at grain boundaries have gradually become clarified, little detailed investigation of the quantitative measurement on the chromium concentration of depleted zone adjacent to the grain boundary has been made hitherto. This report summarizes some of the works on the concentration of chromium-depleted zone which has been investigated from the relationship between the variation of the potential of austenitic steel with applied cathodic current and the change of width of boundary groove that was measured by electron microscopy. It was concluded that the concentration of chromium in the advancing interface with the carbide precipitate growing in an austenitic grain-boundary is less than about 1 pct.