Corrosion behavior of electrodeposited Ni with normal and bimodal grain size distribution

具有均匀和双峰晶粒尺寸分布的电沉积镍的腐蚀行为（英文）

The corrosion behavior of electrodeposited Ni with normal and bimodal grain size distribution was investigated.The microstructure of samples was researched by SEM,EBSD,TEM and XRD.The corrosion behavior was studied by potentiodynamic tests and electrochemical impedance.Nanocrystalline Ni with(100)and(111)textures was prepared by an electrodeposition method.The Ni samples with different grain size distributions and twins were then obtained by heat treatment of nanocrystalline Ni at different temperatures.The effect of grain size on corrosion behavior of the sample depends on the ability of the environment to passivate.In the case where passive film forms on the sample surface,the corrosion resistance of the sample increases with decreasing grain size.Conversely,the corrosion resistance decreases with decreasing grain size when there is no passivation.The corrosion behavior of samples with bimodal grain size distribution obeys the rule of mixture.

研究具有均匀和双峰晶粒分布电沉积镍的腐蚀行为。利用SEM、EBSD、TEM和XRD研究样品的显微组织,利用动电位测试法和电化学阻抗谱研究样品的腐蚀行为。结果表明:电沉积纳米晶镍具有(100)和(111)织构。纳米晶镍经不同温度热处理后,可得到具有不同晶粒尺寸分布的样品。晶粒尺寸对样品腐蚀行为的影响依赖于环境钝化能力。当钝化膜在样品表面形成时,耐蚀性随晶粒尺寸的减小而增强;相反,当样品表面无钝化膜形成时,耐蚀性随晶粒尺寸减小而降低。具有双峰晶粒尺寸分布样品的腐蚀行为遵循混合法则。