The effect of temperature on the corrosion behavior of copper in simulated high-level nuclear waste environment was systematically studied. Electrochemical methods, including electrochemical impendence spectra, Mott–Schottky technology, cyclic polarization, and potentiostatic polarization, were employed to characterize the corrosion behavior of copper at different temperatures. Stereoscopic microscopy and scanning electron microscopy were used to examine the surface morphology, and X-ray photoelectron spectroscopy analysis was used to identify the composition of the passive film. The experimental results show that corrosion resistance of the passive film does not blindly decrease with the increase of temperature but increases at 60℃ owing to a compact outer layer; there is a potential for pitting corrosion, which decreases as the temperature increases. The main product of copper in an anaerobic aqueous sulfide solution is Cu2S but the content of CuS increases at higher temperatures. The whole passivation range shows p-type semiconductor characteristics and the magnitude of the acceptor density is 1023 cm?3, which increases with increasing temperature.%系统研究在高放核废料存储环境下温度对纯铜腐蚀的影响.采用交流阻抗谱、Mott?Schottky技术、动电位以及恒电位极化曲线分析纯铜在不同温度下的腐蚀行为;并采用体视显微镜以及扫描电镜观察样品表面形貌,同时结合X射线光电子能谱分析钝化膜成分.结果表明,钝化膜阻抗并不随着温度的升高而一直降低,在60℃由于致密的外层结构阻抗反常增大;点蚀在此环境下可能发生且钝化膜的点蚀电位随着温度的升高而降低;钝化膜主要成分为Cu2S,而CuS的含量随着温度的升高而增加;钝化膜主要呈p型半导体特性,阳离子空位密度在1023 cm?3数量级且随着温度的升高其密度增大.
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