超声脉冲电沉积镍-氧化锆-氧化铈纳米复合镀层

摘要

A Ni-ZrO2-CeO2 binary nanocomposite coating was prepared by pulsed electrodeposition under ultrasonic condition from the bath containing nickel sulfamate 300 g/L, H3BO3 30 g/L, NH4Cl 5 g/L, wetting agent 0.15 g/L, ZrO2 20 g/L, and CeO2 35 g/L at temperature (45 ± 2) °C and pH 3.8±0.1 for 2 h. The effects of average current density, duty cycle, and pulse frequency on the nanoparticle content of Ni-ZrO2-CeO2 composite coating were studied. The corrosion resistance of the nanocomposite coatings prepared under different pulse parameters in 10%H2SO4 solution was tested by static immersion method. The results showed that the Ni-ZrO2-CeO2 composite coating obtained at average current density4 A/dm2, duty cycle 0.4, and pulse frequency 1 000 Hz has highest nanoparticle content and the most compact surface. The introduction of ultrasound reduces the nanoparticle content of Ni-ZrO2-CeO2 composite coating slightly, but refines the grains and improves the corrosion resistance of the composite coating. Ni-ZrO2-CeO2 composite coating has better corrosion resistance than pure Ni, Ni-ZrO2, and Ni-CeO2 coatings prepared under the same process conditions.%在超声场中采用脉冲沉积法制备了Ni-ZrO2-CeO2二元纳米复合镀层。镀液组成和基础工艺条件为：氨基磺酸镍300 g/L， H3BO330 g/L，NH4Cl 5 g/L，润湿剂0.15 g/L，ZrO220 g/L，CeO235 g/L，温度(45±2)°C，pH 3.8±0.1，时间2 h。研究了平均电流密度、占空比和脉冲频率等对Ni-ZrO2-CeO2复合镀层中纳米颗粒含量的影响。采用静态浸泡法研究了不同脉冲参数下制备的纳米复合镀层在10%H2SO4溶液中的耐腐蚀性。结果表明，在平均电流密度4 A/dm2、占空比0.4、频率1000 Hz条件下脉冲电沉积时，Ni-ZrO2-CeO2复合镀层中纳米颗粒的含量最高，表面最细致。超声波的引入使复合镀层中纳米颗粒的含量有少许降低，但能细化晶粒，提高复合镀层的耐腐蚀性能。Ni-ZrO2-CeO2复合镀层的耐腐蚀性优于相同工艺条件下制备的纯Ni、Ni-ZrO2以及Ni-CeO2镀层。