电沉积Cr－P合金及其耐蚀性的研究

ELECTRODEPOSITION OF Cr-P ALLOYS AND THEIR CORROSION ASSISTANCE

在三价镀铬溶液中添加次磷酸钠，制得了Ｃｒ－Ｐ合金镀层。研究了电沉积条件对镀层成份的影响和镀层在１ｍｏｌ／Ｌ盐酸和０．５ｍｏｌ／Ｌ硫酸中的电化学行为。磷含量大于５ｗｔ％时，合金镀层具有极好的耐蚀性。

Cr-P alloys were deposited from the bath for chormium (Ⅲ) electrodeposition containing NaH2PO2.The effects of some electroplating parameters on P content in the obtained deposits were evaluated. The P content increased with decreasing cathodic current density and with increasing H2PO concentration in the bath. Tile anodic polarization behavior of the deposits in 0.5 mol/L H2SO4 and 1 mol/L HCl was examined. When tile P content exceeded 5 wt%, the deposited alloy exhibited excellent corrosion resistance and the passive current density was only 10-50μA/cm2.