B10铜镍合金海水加速腐蚀行为

摘要

B10 Cu-Ni alloy has good corrosion resistance against seawater.Natural seawater from Xiamen,was used to study the seawater corrosion behaviour of B10 Cu-Ni alloy,H2O2 was added as corrosion accelerator.The whole seawater immersion corrosion simulation experiments were conducted in laboratory.Geometric measurement and electrochemical impedance spectroscopy (EIS) technique were used to obtain the tendency of corrosion rate versus corrosion time.The growth and damage of the oxidation film on the surface of the alloy of 1cm2 working area were characterized by the impedance spectra features with different corrosion time.Scanning electron microscope(SEM),energy spectrum analysis(EDX),X-ray photoelectron spectroscopy(XPS) and raman spectrum were used to analyse the constitution of corrosion product and the corrosion types.The results show that the instantaneous corrosion rate exhibits decreasing first then increasing due to the state of oxidation film.The corrosion products consist of Cu2 (OH)3Cl and Cu2O.And the corrosion of B10 Cu-Ni alloy starts with pitting corrosion,then gradually goes through the evolution process of intergranular corrosion to exfoliation.%B10铜镍合金具有优良的耐海水腐蚀性能,为研究其在海水中的腐蚀行为,取厦门天然海水,加入双氧水作为腐蚀加速剂,在室内模拟海水全浸腐蚀实验,采用失重法、电化学阻抗谱(EIS)技术分析B10合金在海水腐蚀中的腐蚀速率随腐蚀时间的变化规律,用不同腐蚀周期的电化学阻抗谱特征来表征工作面积为1 cm2的合金表面氧化膜的生长破坏情况.结合扫描电子显微镜(SEM)、能谱分析(EDX)、XPS和拉曼光谱技术分析B10合金表面腐蚀产物膜的成分以及B10合金在海水腐蚀中的腐蚀类型.结果表明,氧化膜的生成与破坏使得合金在海水中的瞬态腐蚀速率呈先减小后增大的趋势,腐蚀产物包含碱式氯化铜Cu2 (OH)3Cl和氧化亚铜Cu2O,腐蚀由点蚀开始,逐渐经历了晶间腐蚀-剥蚀.