中温高磷化学镀镍复合配位剂的研究

摘要

在中温(75 ℃)下以乳酸为主配位剂进行化学镀镍,研究了不同辅助配位剂的浓度对沉积速率和镀层磷含量的影响.对配位剂进行正交复配试验,得到最优组合为:乳酸10 mL/L,柠檬酸0.03 mol/L,DL-苹果酸0.06 mol/L,丙二酸0.05 mol/L.采用最优组合复合配位剂时,镀液稳定性好,在中温条件下的沉积速率为5.66 μm/h,镀层中磷的质量分数为1 1.78％,外观光亮细致,结合力良好,孔隙率低于0.24个/cm2,耐硝酸点蚀的时间超过180 s,耐中性盐雾96 h以上,镀层综合性能优良.%The effects of different auxiliary complexing agents on the deposition rate of electroless nickel plating at medium temperature (75 ℃) and the phosphorus content in nickel coating were studied using lactic acid as primary complexing agent. The optimal formulation of the composite complexing agent was determined by orthogonal test as follows: lactic acid 10 mL/L, citric acid 0.03 mol/L, DL-malic acid 0.06 mol/L, and malonic acid 0.05 mol/L. The bath is stable and the deposition rate for electroless nickel plating at medium temperature is 5.66 um/h when using the optimal formulation of composite complexing agent. The nickel coating obtained from the bath is characterized with phosphorus content 11.78wt%, bright and uniform appearance, good adhesion, porosity below 0.24 pores/cm2, nitric acid spot corrosion time ＞180 s, and neutral salt spray time ＞96 h, showing good comprehensive performance.