Spent nuclear fuels (SNFs) are expected to be stored in dry storage canisters (DSCs) for much longer time than earlier anticipated due to a lack of permanent deep geological repository. As a result, DSCs located in marine environment may undergo chloride induced stress corrosion cracking (SCC) during long-term storage of SNFs. We report here the effect of test temperature on accelerated crack growth experiments carried out on sensitized austenitic stainless steel SS304H in substitute ocean water using fracture mechanics approach. Wedge-opening loading specimens were selected for measurement of crack growth rates using direct-current potential drop technique. Average crack growth rates of 0.975 × 10⁻¹⁰ ± 9.528 × 10^-12, 3.258 × 10⁻¹⁰ ± 9.551 × 10^-11 and 1.580 × 10^-9 ± 2.593 × 10⁻¹⁰ m/s were obtained for 22, 37 and 60 °C, respectively resulting in an activation energy of 60.9 kJ/mol corresponding to diffusion of hydrogen in steel. Intergranular crack propagation was noted along with formation of chromium-rich carbide precipitates at grain boundaries.

由于缺乏永久性的深层地质库，预计用过的核燃料（SNF）在干式储存罐（DSC）中的存储时间将比早先的预期更长。因此，位于海洋环境中的DSC在SNF的长期存储过程中可能会发生氯化物诱导的应力腐蚀开裂（SCC）。我们在这里报告了使用断裂力学方法，测试温度对替代海水中敏化奥氏体不锈钢SS304H进行的加速裂纹扩展实验的影响。选择楔形张开载荷样品，以使用直流电势下降技术测量裂纹扩展速率。的0.975×10平均裂纹增长速率^-10 ±9.528×10 ^-12，3.258×10 ^-10 ±9.551×10^在22、37和60°C下分别获得^-11和1.580×10 ^-9 ±2.593×10 ^-10 m / s的活化能，对应于钢中氢的扩散，活化能为60.9 kJ / mol。观察到晶间裂纹扩展以及在晶界形成富铬碳化物沉淀。