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.
|Number of pages||13|
|Journal||Transactions of Nonferrous Metals Society of China (English Edition)|
|Publication status||Published - 1 Feb 2019|