化学镀Ni－P合金层耐蚀性能的研究

通过中性盐雾试验、极化曲线测验、Ｘ射线衍射和扫描电镜等手段研究了影响化学镀Ｎｉ－Ｐ合金镀层耐蚀性能的各种因素。认为镀层的含磷量随镀液中次磷酸钠浓度、络合剂浓度或镀液温度的增高而提高，但随镀液ｐＨ值的增高而减低。而含磷量较高的镀层具有较高的耐蚀性能。研究还表明，镀件在化学镀前经过抛光处理会有助于提高镀层的耐蚀性。而镀后在高温度下的热处理，则会使镀层的耐蚀性变差。

Investigation of Corrosion Resistance of Electroless Ni-P Deposits

actors influencing corrosion resistance of electroless Ni-P alloy deposits were studied by means of neutral salt spray, polarization curves, X-ray diffraction and scanning electron microscope. The results showed that increasing bath concentration of hypophosphite and complexing agent or operating temperature results in increase of phosphorus content in the deposit, but increasing bath pH value leads to decrease of such content. Deposit with higher phosphorus content offers a higher corrosion resistance. The results also indicated that chemical polishing before electroless plating helps to improve corrosion resistance of the deposit but heat treatmentlunder a relatively high temperature bas adverse influence on the resistance.