电镀Zn-Fe合金工艺研究

Research on Technology for Electroplating of Zn-Fe Alloy

介绍了一种电镀Zn-Fe合金的工艺,研究了阴极电流密度、镀液中ρ(Fe2+)/ρ(Zn2+)、pH、温度和添加剂等因素对镀层的外观以及Fe质量分数的影响。实验结果表明,镀层中Fe的质量分数随着镀液中ρ(Fe2+)/ρ(Zn2+)、pH的增大而增大;随着阴极电流密度的增大、温度的升高先增大,达某一值时镀层中Fe的质量分数又随其增大而减小。通过3%NaC l腐蚀试验,比较了Zn-Fe合金和Zn镀层的耐腐蚀性。在最佳工艺条件下所得Zn-Fe合金镀层的耐腐蚀性为Zn镀层的5倍。

A novel acidic electrodeposition technology for Zn-Fe alloy was proposed. Zn-Fe alloys with different composition and morphology were obtained by changing the deposition variables, such as cathodic current density （JK）, ρ （Fe^2＋）/ρ （ Zn^2＋ ） in the bath, pH, temperature and additives. The results show that the Fe content in the deposits is increased with the increase in ρ（ Fe^2＋ ）/ρ（ Zn^2＋ ） and pH. However, with the gradually increase in cathodic current density and temperature, Fe content of the deposits is increased to a fixed value, then decreased. The morphology and corrosion resistance property of the Zn-Fe deposits were compared with those of Zn deposits by using 3% NaCl aqueous solution and scanning electron microscope （SEM）. The corrosion resistance of the Zn-Fe alloy deposits, obtained from the optimum bath, is 5 times as high as that of Zn deposits.