镀液成分对化学镀镍层性能的影响

Effect of bath components on the properties of electroless nickel plating

研究了镀液成分对Q235钢化学镀镍层性能的影响。由正交试验分析可知,硫酸镍对镀速的影响最大,次亚磷酸钠次之,乳酸的影响最小;综合考虑各因素,得到的化学镀镍最佳工艺配方为硫酸镍30 g/L,次亚磷酸钠25 g/L,乳酸30 mL/L,温度70℃,pH值为5.0。试验结果表明,镀层耐腐蚀性能良好,腐蚀速率低至0.0002μm/h,镀层镀态硬度高达490.8 HV0.05,经热处理后硬度达1351 HV0.05。由扫描电子显微镜分析显示,镀层表面光滑平整、致密;通过能谱仪分析可知,镀层中Ni含量为91.92%(wt),P含量为6.53%(wt)。

The influences of bath components on properties of nickel deposits on Q235 steel substrate were investigated.The orthogonal experiment results show that the influence of nickel sulphate is strongest on the plating rate,the next is sodium hypophosphite and the last is lactic acid.After comprehensive analyses of all the influence factors,the optimum technological recipe was obtained,namely,nickel sulphate 30 g/L,sodium hypophosphite 25 g/L,lactic acid 30 mL/L with the plating temperature 70 ℃ and pH value 5.0.The results show that the coating possesses good anticorrosive property and the corrosion rate is as low as 0.0002 μm/h.The deposits have hardness of 490.8 HV0.05 as plated and 1351 HV0.05 after heat treatment.The deposits display smooth,flat and compact character through SEM analysis.The analyses of X-ray energy disperse indicate that the nickel content is 91.92%（wt）and the phosphorescence content is 6.53%（wt）in the deposit.