(中南大学 材料科学与工程学院，长沙 410083)
摘 要: 利用循环伏安方法和恒电位阶跃技术研究Ni-SiC复合镀层电沉积行为。结果表明：Ni-SiC复合镀层和纯Ni镀层的形核/生长过程符合Scharifker-Hill三维成核模型；在低过电位下，Ni-SiC复合镀层形核/生长过程按三维连续成核机制；高过电位下，形核/生长过程遵循瞬时成核机制，与纯Ni镀层的形核/生长过程具有一致性；无论Ni-SiC复合镀层还是纯Ni镀层，形核弛豫时间tm随负电位的增大呈现有规律递减趋势，相应的Im值基本相近；SiC粉体的引入导致Ni形核的过电位正移和tm的显著减小。
关键字: 电结晶；形核；循环伏安；恒电位阶跃
（School of Materials Science and Engineering, Central South University, Changsha 410083, China）
Abstract:The electroplating behavior of fabricating Ni-SiC composite film (NS) was investigated using chronoamperometry method in conjunction with the cyclic voltammetry method. The results show that, in the case of lower electroplating negative voltage, the co-deposition of Ni-SiC film follows a 3-D progressive nucleation/growth mechanism. While in the case of higher electroplating negative voltage, it follows a 3-D instantaneous nucleation/growth mechanism. However, either Ni-SiC co-deposition coatings or pure Ni coatings, the nucleation relaxation time tm decreases regularly with the increase of the negative potential, while the corresponding current Im are almost in the same quantity. Obviously, because of addition of SiC powder, the nucleation potential of Ni turns to positive direction, and the nucleation relaxation time tm decreases clearly.
Key words: electrocrystallization; nucleation; cyclic voltammetry; potentiostatic transients
