磷对锌-镍合金耐蚀性的影响

Influence of Phosphorus on the Corrosion Resistance of Zn-Ni Alloys

以次磷酸钠为磷元素来源,研究了磷对锌-镍合金的电化学过程、成分、表面形貌和耐蚀性的影响。实验发现:磷需要在镍表面的催化作用下才能析出,镍和磷的沉积过程属于协同效应。磷的质量分数提高,有利于增大锌-镍合金中镍的质量分数,改善锌-镍合金的耐蚀性。然而,次磷酸钠过量会使得镀液的稳定性下降,锌-镍合金表面疏松、发黑,耐蚀性变差。

Sodium hypophosphite was used as phosphorus element resource, and the influence of phosphorus on the electrochemistry process, composition, surface morphology and corrosion resistance of Zn-Ni alloys was investigated. Experiment showed that, phosphorus could be deposited on the surface of nickel through catalytic action. Deposition of phosphorus and nickel belong to a kind of synergistic effect. The increase of the mass fraction of phosphorus was benefit to increase the mass fraction of nickel in Zn-Ni alloys, resulting in improvement in the corrosion resistance of Zn-Ni alloys. However, higher content of sodium hypophosphite degrade the stability of plating solution, and resulting in porous and black surface, then weaken the corrosion resistance of Zn-Ni alloys.