镍基合金镀层在北方老工业城市冬季降水中的腐蚀行为
Corrosion behavior of nickel base alloy coatings in the winter precipitation contamination of Chinese north old industrial city
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摘要: 为研究镍基合金镀层在北方老工业城市冬季降水中的腐蚀行为,采用电沉积技术制备了Ni-P、Ni-Fe合金镀层,对其结构与耐蚀性能进行检测.结果表明:不同镍基合金镀层在冬季降水中耐蚀性能不同,其中Ni-Fe合金镀层由于Fe掺杂增加了镍基合金与氧的亲和力,可以快速在Ni-Fe合金镀层表面形成一层连续的氧化膜,对基体起到很好的防护作用,电位最正,自腐蚀电流密度值最小,耐蚀性较好,年腐蚀速率约为20号钢的1/2;而Ni-P合金镀层表面形成氧化膜的速率较缓慢,阻抗值较低,不适合在北方老工业城市的室外装饰与防护中应用.Abstract: In order to study the corrosion behavior of nickel-based alloy coatings in the winter precipitation of Chinese north old industrial city,Ni-P and Ni-Fe coatings were prepared by electrodeposition,and the phase structure and corrosion resistance of the nickel coatings were examined.Experimental results show that the corrosion resistances of different nickel coatings are different.The Ni-Fe coating has a nobler potential,a lower corrosion current density and a better corrosion resistance.Its corrosion rate is about half of 20 Steel's one.This is because that Fe in the nickel coating has a greater affinity with oxygen and can form a continuous oxide film quickly on the surface of the Ni-Fe coating.But the oxide film on the Ni-P coating forms slowly and its impedance resistance is lower than that of the Ni-Fe coating.Thus the Ni-P coating is not suitable to be used for outdoor decoration and corrosion protection in Chinese north old industrial city.