【摘要】 为了解释锆合金在LiOH水溶液中耐腐蚀性能降低的原因,将3组粉状Zr-4合金样品分别放在500℃空气中、500℃过热蒸汽中和350℃的0.1mol/LLiOH水溶液中进行腐蚀,当氧化膜厚度约为1.5μm时,用XRD分析这3组样品的晶体结构。将一片状Zr-4合金样品在350℃的0.04mol/LLiOH水溶液中腐蚀2d,用SIMS检测Li+和OH-在氧化膜剖面上的分布。根据实验结果提出OH-在氧化膜中比O(-2)~扩散速度快,使t-ZrO2加速向m-ZrO2转变,导致Zr-4合金腐蚀速度加快。更多还原

【Abstract】 In order to understand the degradation behavior of Zircaloy-4 corroded in LiOH aqueous solution, three groups of Zr-4 powder specimens are exposed in 500℃ air, 500℃ superheated steam, and 0.1 mol/L LiOH aqueous solution at 350℃ respectively, till the thickness of the oxide film is about 1.5 μm. XRD is performed on the specimens to distinguish the oxide crystal structure. A Zr-4 plate specimen is exposed in 0.04 mol/L LiOH solution at 350℃ for 2 d, then SIMS is carried out to obtain the Li+ and OH- profiles in the oxide film. Based on the results, it is put forward that OH- diffuses faster than O-2 does in the oxide film and can enhance the transformation from t-ZrO2 to m-ZrO2, which quickens the corrosion rate of Zircalor-4.更多还原