发光化学镍复合镀层(英文)

Light-emitting electroless nickel composite coating

在90°C下,采用含有25g/L硫酸镍、20g/L次磷酸钠、35g/L柠檬酸钠、0～6g/L卤磷酸钙和15g/L硫酸铵的镀液(pH5.5),制备了基于卤磷酸钙的发光化学镍复合镀层。研究了镀液pH对复合镀层的沉积速率及卤磷酸钙含量的影响。采用硬度测量、磨损测试、腐蚀试验、紫外光谱、扫描电镜和X射线衍射对复合镀层进行了表征。在最佳卤磷酸钙质量浓度(4g/L)下所得的复合镀层含77.59%(质量分数)镍、7.58%(质量分数)磷和14.83%(质量分数)卤磷酸钙。由于卤磷酸钙是硬质粒子,随着其嵌入量的增多,复合镀层的硬度增大。在存在卤磷酸钙的条件下,化学镍复合镀层的耐磨和耐蚀性能均显著提高。

Light-emitting electroless nickel composite coatings based on calcium halophosphate were prepared from a bath containing nickel sulfate 25 g/L, sodium hypophosphite 20 g/L, trisodium citrate 35 g/L, calcium halophosphate 0-6 g/L and ammonium sulfate 15 g/L at a temperature of 90 ℃ and pH 5.5. The effect of pH on deposition rate and calcium halophosphate content in composite deposit was studied. The composite coatings were characterized by hardness measurement, abrasion testing, corrosion testing, ultraviolet spectroscopy, scanning electron microscopy and X-ray diffraction. The composite deposit obtained at the optimal mass concentration （4 g/L） of calcium halophosphate in bath contains Ni 77.59%, P 7.58% and calcium halophosphate 14.83% （all in mass fraction）. The hardness of composite deposit was increased with increasing incorporation of calcium halophosphate due to the hard nature of calcium halophosphate particles. The wear and corrosion resistance of electroless nickel composite coating were greatly improved in the presence of calcium halophosphate particles.