(1. 国网浙江省电力公司 电力科学研究院, 杭州 310014;
2. 南昌航空大学 材料科学与工程学院,南昌 330063)
摘 要: 在测定Ni-金刚石复合电沉积体系阴极极化曲线、电化学阻抗谱及微分电容曲线等基础上,分析了温度对界面双电层的影响规律,推断出金刚石微粒复合量随温度升高的变化趋势,以此探讨温度在Ni-金刚石复合电沉积中的电化学行为。结果表明:随镀液温度沿30 ℃→40 ℃→60℃升高,Ni-金刚石复合体系的阴极极化减小,法拉第电阻沿17.3 ?→5.2 ?→3.0 ?降低,双电层电容沿40.8 μF→141.2 μF→175.6 μF增加,同时,阴极表面在析出电位附近的负电荷密度逐渐增加。电化学测试结果表明:金刚石微粒复合量将随温度的升高而降低,且工艺实验与电化学测试结果也映证这一点。
关键字: Ni-金刚石;复合电沉积;电化学行为;阴极极化曲线;电化学阻抗谱
(1. Electric Power Research Institute, State Grid Zhejiang Electric Power Company, Hangzhou 310014, China;
2. Institute of Materials Science and Engineering, Nanchang Hangkong University, Nanchang 330063, China)
Abstract:Based on the study about cathodic potentiodynamic diagrams, electrochemical impedance diagrams and differential capacitance curves, the effect of temperature on diffuse double layer was analyzed, and then the change of particle content in the deposits along with temperature was judged. And the electrochemical action of temperature in Ni-diamond composite electrodeposition was discussed. The results show that, with temperature increasing from 30 ℃, 40 ℃ to 60 ℃, the cathodic potentiodynamic of composite system decreases. At the same time, Faraday resistance decreases from17.3 ?, 5.2 ? to 3.0 ?, the electric double layer capacitance increases from 40.8 μF, 141.2 μF to 175.6 μF. The negative charge density on cathodic surface increases near deposition potential. The electrochemistry testing experiment data indicate that the content of particles in the deposits decreases with the increase of temperature. The technics experiment confirms it well.
Key words: Ni-diamond; composite electrodeposition; electrochemical behavior; cathodic potentiodynamic diagram; electrochemical impedance diagram