- 著者
-
KISHIDA Kazuo
YAMAWAKI Michio
KANNO Masayoshi
- 出版者
- Atomic Energy Society of Japan
- 雑誌
- Journal of Nuclear Science and Technology (ISSN:00223131)
- 巻号頁・発行日
- vol.15, no.12, pp.919-925, 1978
Corrosion of Type 304 stainless steel by molten Cs<SUB>2</SUB>O<SUB>3</SUB>-CsO<SUB>2</SUB> has been investigated at 690 and 800°C. The Cs<SUB>2</SUB>O<SUB>3</SUB>-CsO<SUB>2</SUB> mixture was selected as corroding agent in order to clarify the corrosion behavior of stainless steel at a considerably high oxygen potential. At the initial stage a uniform Fe<SUB>3</SUB>O<SUB>4</SUB> layer is formed and is then removed. After the removal of the oxide film intergranular penetration proceeds into the alloy substrate. Chromium-containing oxides are formed as corrosion products at the grain boundaries. After the grain boundary penetration has continued for a while, a Cr-depleted surface alloy layer is formed, which blocks further progressing of the intergranular penetration. Then, this Cr-depleted layer is detached, inducing the restart of the intergranular pene-tration. Compared to the reported intergranular penetration rates of stainless steel due to Cs<SUB>2</SUB>O-Cs<SUB>2</SUB>O<SUB>2</SUB>, those due to Cs<SUB>2</SUB>O<SUB>3</SUB>-CsO<SUB>2</SUB> obtained in this study were generally lower, and changed in a more complicated fashion with time.