探讨了氢氧化钠、碳酸钠、磷酸钠和硅酸钠单独或协同作用对化学镀镍层钝化的影响,并以正交设计试验确定了上述四种组成的最佳浓度.为增强钝化效果,研究了高锰酸钾质量浓度、钝化温度和时间对钝化效果的影响.结果表明,钝化液的最佳组成为10g/L氢氧化钠,15 g/L碳酸钠,50 g/L磷酸钠,5g/L硅酸钠,1g/L高锰酸钾,θ为80℃,t为20 min.化学镀镍层经无铬钝化液处理后,镀层抗腐蚀能力显著提高.%Influences of sodium hydroxide, sodium carbonate, sodium phosphate, sodium ailicate content on the passivation for electroless nickel coating were investigated under alkaline condition with addition a-lone or joint addition. The optimal concentration of the above four contents were determined by orthogonal experiments. In order to improve the passivation effect, influences of potassium permanganate concentration , temperature and time were also measured. Results showed that the optimal compositions of passivation solution were sodium hydroxide of 10g/L,sodium carbonate of 15 g/L,sodium phosphate of 50 g/L, sodium silicate of 5 g/L,potassium permanganate of 1 g/L,temperature of 80 ℃ and time of 20 min. After treated by this chromium free passivation solution, corrosion resistance of the electroless nickel coating was significantly increased.
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