化学镀时间对Ni-Co-P合金镀层性能的影响

Effect of Electroless Plating Time on Properties of Ni-Co-P Alloy Coating

采用化学镀技术在铜基体上制备了Ni-Co-P合金镀层,研究了化学镀时间对镀层微观形貌、厚度、显微硬度和耐腐蚀性能的影响。结果表明:化学镀20~120 min时的镀层都呈胞状形貌,且都含有Ni、Co、P、C和O五种元素。随着化学镀时间延长,镀层微观形貌发生变化,Ni和P元素质量分数总体呈升高的趋势,Co元素质量分数总体呈降低的趋势,厚度呈现出先显著增加后缓慢增加的趋势,显微硬度在325~542 HV之间呈先增大后趋于稳定的趋势,耐腐蚀性能逐渐改善。化学镀120 min时的镀层表面较为平整致密,胞状物的尺寸明显减小,显微硬度达到542 HV,在氯盐溶液和弱碱性溶液中都表现出相对较好的抗腐蚀能力。

Ni-Co-P alloy coating was prepared on the surface of copper substrate by electroless plating,and the effects of electroless plating time on the microstructure,thickness,microhardness and corrosion resistance of the coatings were studied.The results showed that the coatings obtained at different electro⁃less plating time(20-120 min)presented cellular morphology,and each coating was composed of Ni,Co,P,C and O elements.With the extension of electroless plating time,the microstructure of the coating was changed,and the mass fraction of Ni and P in the coating generally increased,while the mass fraction of Co generally decreased.The thickness of the coatings increased significantly first and then slowly.The microhardness between 325 and 542 HV increased first and then stabilized,and the corrosion resistance was gradually improved.When the electroless plating time was 120 min,the coating exhibited a relatively smooth and compact surface,and the microhardness reached 542 HV.Moreover,the coating showed good corrosion resistance in both chlorine salt solution and weakly alkaline solution.