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采用脉冲电沉积法制备纳米晶镍镀层,利用扫描电镜、透射电镜及XRD对不同糖精钠浓度下制得的镍镀层的微观结构进行了表征,采用显微硬度计、DSC及全电位测试仪对镀层的硬度、热稳定性和耐蚀性进行研究。结果表明:镍镀层晶粒尺寸随着糖精钠浓度升高先增后降,浓度为10g/L时晶粒尺寸最小;当浓度低于15g/L时,镀层表面较为光滑、明亮;镍镀层的显微硬度在糖精钠浓度为10g/L时达到最大值,显微硬度与平均晶粒尺寸的关系基本符合Hall-Petch方程;镍层晶粒的失稳长大温度随糖精钠浓度的增加在305℃上下波动;当糖精钠浓度为10g/L时,镍层的耐蚀性最好。
Nanocrystalline nickel coatings were prepared by pulse electrodeposition. The microstructure of nickel coatings prepared under different saccharin concentrations were characterized by scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The microhardness, DSC and potentiostatic The hardness, thermal stability and corrosion resistance of the coating were investigated. The results showed that the grain size of nickel coating first increased and then decreased with the increase of sodium saccharin concentration. When the concentration was 10g / L, the grain size was the smallest. When the concentration was lower than 15g / L, the surface of coating was smooth and bright. The hardness reaches the maximum value when the sodium saccharin concentration is 10g / L. The relationship between the microhardness and the average grain size basically accords with the Hall-Petch equation. The instability temperature of the nickel layer increases with the increase of sodium saccharin concentration at 305 ℃ Up and down fluctuations; when the sodium saccharin concentration of 10g / L, the best corrosion resistance of the nickel layer.