使用済燃料プールから取り出した燃料集合体の長期健全性評価,3; 線照射下希薄人工海水での異材すきま試験片を用いた電気化学試験

Evaluation of long-term integrity of the fuel assembly removed from the spent fuel pool, 3; Electrochemical test of galvanic specimen with crevice in dilute artificial seawater under -ray irradiation

本岡 隆文; 上野 文義  

Motooka, Takafumi; Ueno, Fumiyoshi

燃料集合体を構成するZrとSUS304Lのすきまを対象に、Co-60線照射下で、室温の希薄人工海水におけるすきま腐食発生条件を電気化学的手法により調査した。福島第一原子力発電所の使用済燃料プール環境を模擬した条件では、腐食すきま再不動態化電位は定常腐食電位より高く、異材構造部ですきま腐食は発生困難なことが示唆された。

Crevice corrosion of a couple of zirconium and SUS304L were investigated in dilute artificial seawater at ambient temperature under Co-60 -ray irradiation by electrochemical technique to clarify the occurrence criteria of crevice corrosion. Under simulated an aqueous circumstance in spent fuel pools in Fukushima Daiichi nuclear plant, crevice corrosion potential was greater than spontaneous potential. This result suggests that crevice corrosion little occurs in the dilute chloride solution simulating the spent fuel pool circumstance.