改良型オーステナイト鋼のFCCI特性試験; 仏国製改良オーステナイト鋼およびSUS316相当鋼大気溶解材

Corrosion tests for the evaluation of FCCI susceptibility of advanced austenitic stainless steel; Advanced austenitic stainless steel of french manufacture and modified SUS316 stainless steel fablicated by air melting method

湯谷 順明*; 和田 孝志*; 松塚 龍二*; 山中 康靖*; 渡 孔男*

Yutani, Toshiaki*; Wada, Takashi*; Matsuzuka, Ryuji*; Yamanaka,Tsuneyasu*; Watari, Yoshio*

仏国製改良オーステナイト鋼被覆管とSUS316相当鋼大気中溶解材を用いた被覆管のFCCI特性を把握するため、SUS316相当鋼真空二重溶解材をレファレンス材とし、CsOH-CsI混合物、Teおよびヨウ素を模擬FP腐食剤として、温度700、時間100hの条件で、炉外腐食試験を行い、以下の結果を得た。(1)CsOH-CsI混合物(CsOH/CsI=1)により、粒界腐食が生じた。(2)Teおよびヨウ素により全面腐食が生じた。(3)3供試材間に腐食形態の相違はなかった。(4)Teの場合を除いて、仏国製改良オーステナイト鋼とSUS316相当鋼大気中溶解材は、SUS316相当鋼真空二重溶解材と同程度の耐食性を示した。

To evaluate the corrosion resistance due to fuel-cladding chemical interaction (FCCI), corrosion tests of an advanced austenitic stainless steel of French manufacture and modified SUS316 stainless steel fabricated by air melting method and doble vacuum melting method with CsOH-CsI mixture, tellurium and iodine were conducted at 700C for 100 hours. The result were summarized as follows. (1)The CsOH-CsI mixture (CsOH-CsI=1) produced intergranular attack, (2)Tellurium and iodine produced matrix attack. (3)There were little difference in corrosion morphology between three alloys. (4)Advanced austenitic stainless steel and modified SUS316 stainless steel farbricated by air melting method had almost same corrosion resistances to CsOH-CsI mixtures and iodine as modified SUS316 stainless steel farbricated by double vacuum melting method.