W含量对化学镀Ni-W-P镀层的影响研究

The Effect of Content of W on Electroless Ni-W-P Coating

为提高化学镀Ni-W-P镀层的耐蚀性,拓宽其应用,采用单因素试验方法,研究了镀液中Na2WO4.2H2O的浓度对化学镀Ni-W-P镀层的耐蚀性能的影响。结果表明,钨酸钠浓度为20g/L时,镀层的耐蚀性能最好。应用扫描电镜和X射线衍射分析了镀层的微观形貌和组织结构,结果表明,W含量的变化影响了镀层胞状组织的尺寸,镀层的组织致密和非晶态结构是其耐蚀性能高的重要原因。

Aimed at improving corrosion resistance of electroless Ni-W-P plating and extend its application field, the effect of Na2WO4 · 2H2O content in solution was investigated on corrosion resistance of layer by using single factor experiments. The results showed that corrosion resistance of the coating was the best when the content of Na2WO4· 2H2O is 20 g/L. By means of SEM, microscopic morphology of the layer was analyzed, and the results showed that the texture was dense when content of Na2WO4 · 2H2O is 20 g/L. Variation of W content influenced the grain size and the performance of film. It was found that the dense amorphous structure is the most important aspects to improve the corrosion resistance of the coatings.