施镀工艺对镍−石墨烯复合化学镀层性能的影响

Effect of electroless plating process on properties of nickel-graphene composite coating

以2A12铝合金为基体进行镍−石墨烯复合化学镀。镀液组成为:次磷酸钠32 g/L,六水合硫酸镍28 g/L,一水合柠檬酸15 g/L,乳酸25 mL/L,醋酸钠15 g/L,十二烷基苯磺酸钠20~40 mg/L,石墨烯粉末(粒径为3~5μm)40~140 mg/L。通过单因素试验和正交试验研究了石墨烯添加量、施镀温度和镀液pH对沉积速率及镍−石墨烯复合镀层显微硬度和耐蚀性的影响。得到最优工艺条件为:石墨烯添加量120 mg/L,施镀温度88°C,镀液pH 5.0。在最佳工艺条件下,沉积速率为13.55μm/h,所得镍−石墨烯复合镀层的显微硬度为497.82 HV,石墨烯在镀层中分布均匀。

Electroless plating of nickel–graphene composite was conducted on 2A12 aluminum alloy substrate.The bath composition was as follows:sodium hypophosphate 32 g/L,nickel sulfate hexahydrate 28 g/L,citric acid monohydrate 15 g/L,lactic acid 25 mL/L,sodium acetate 15 g/L,sodium dodecylbenzenesulfonate 20-40 mg/L,and graphene powder(3-5μm in diameter)40-140 mg/L.The effects of graphene dosage,plating temperature,and bath pH on the deposition rate,microhardness,and corrosion resistance of nickel–graphene composite coating were studied by single-factor experiment and orthogonal test.The process conditions were optimized as follows:graphene dosage120 mg/L,plating temperature 88°C,and bath pH 5.0.The nickel–graphene composite coating obtained thereunder had a deposition rate of 13.55μm/h and a microhardness of 497 HV with uniform distribution of graphene.