Retraction; Estimation of corrosion rate of Zr-2.5wt%Nb alloy (Fugen pressure tube) under low-temperature, low-oxygen, and high-pH conditions

Sakatani, Keiichi; Nakatani, Takayoshi ; Funabashi, Hideyuki 

The safety assessment of the sub-surface disposal system should ensure that calculated dose rate will be lower than the dose rate assigned to the scenario in question over the whole evaluation period. For activated metal wastes which are the reactor structural materials classified as one of the subject wastes, the rate of nuclide elution under the disposal environment is an important parameter in safety assessment. Some reports have shown that nuclides in a metal matrix are released with corrosion congruently. However, the corrosion rate under low temperature, low oxygen and high pH conditions assuming the disposal environment is not reported about Zr-2.5wt%Nb alloy, which is used in the pressure tube of Fugen (ATR). The gas-accumulating type corrosion test on Zr-2.5wt%Nb alloy was conducted in order to obtain corrosion rate. The corrosion rate after 1 month, 3 months, 6 months, 12 months and 24 months was obtained during the test period.