亜鉛-ニッケル合金めっき鋼板の腐食過程 [in Japanese] Corrosion Process of Zinc-Nickel Alloy Electroplated Steel [in Japanese]
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In order to examine the corrosion process of Zn-Ni alloy electroplated steel in a solution containing chlorine ions (3%NaCl aqueous solution), the time dependence of the corrosion potential was measured during an immersion test and the corrosion products were analyzed by XPS. The corrosion potential shifted to a noble potential in a complex manner as corrosion proceeded. The shift of the corrosion potential was characterized by the following corrosion process. At the beginning of corrosion, selective dissolution of Zn occured, and Zn oxide or hydroxide formed as a corrosion product on the surface of the Zn-Ni alloy plating. In the early stages of corrosion, the thickness of the corrosion product layer increased. As corrosion progressed, ZnCl<sub>2</sub>·4Zn(OH)<sub>2</sub> formed outside the Zn oxide (hydroxide) layer. Therefore, the surface of the Zn-Ni alloy electroplated steel took on a layered structure of ZnCl<sub>2</sub>·4Zn(OH)<sub>2</sub>/Zn oxide or hydroxide/Zn oxide or hydroxide+metallic Ni/steel substrate. Dissolution of iron from the underlying steel occurs by passing through these corrosion products layers.
- Jitsumu Hyomen Gijutsu
Jitsumu Hyomen Gijutsu 48(2), 206-212, 1997-02-01
The Surface Finishing Society of Japan