Fe-36%Ni 合金の粒界選択酸化に及ぼす引張応力の影響

概要

論文の詳細を見る
The oxidation of an Fe-36%Ni alloy (invar type alloy) is investigated at temperatures between 1000K and 1300K in air under tensile stress conditions using metallographic, electron probe microanalysis, and X-ray diffraction techniques. The oxide scales consist of an external scale and a subscale which has an intragranular oxidation zone and an intergranular oxidation zone. The oxide phases in each scale are identified as FeO, Fe_3O_4, and Fe_2O_3 and FeO and Fe_3O_4, respectively. The oxide phases do not depend on the magnitude of tensile stress within 14.7MPa, but the growth rates of scales depend on remarkably. The growth rates of the intragranular oxidation zone increase (below 1100K) or decrease (above 1200K) with increasing tensile stress, but those of the intergranular oxidation zone increase (above 1200K) with increasing tensile stress. The formation of intergranular oxide is promoted not only in the direction of depth from a surface, but also in the width (thickness) of oxide with increasing tensile stress. The stress accelerated grain boundary oxidation (SAGBO) in this alloy is confirmed distinctly.
社団法人日本鉄鋼協会の論文
1998-04-01