电沉积制备Ni-Co合金镀层的成核过程研究

在氨基磺酸盐镀液中,采用电沉积技术制备了Ni-Co合金镀层。通过阴极线性扫描和计时电流测试,研究了Ni-Co合金镀层电结晶初期的共沉积行为和电化学反应过程,探究了Ni-Co合金镀层的成核模型;采用扫描电子显微镜和X射线衍射仪,表征了Ni-Co合金镀层的表面形貌和微观结构;通过退火后的显微硬度测试,研究了Ni-Co合金镀层的热稳定性。结果表明:Ni-Co合金镀层的沉积电位约为-0.73 V;Ni-Co合金镀层的形核/生长过程符合受扩散控制的瞬时成核模型;Ni-Co合金镀层表面均匀致密,晶粒细小,热稳定性较好。

Investigation on Nucleation Process of Ni-Co Alloy Coating Prepared by Electrodeposition

Ni-Co alloy coating was prepared by electrodeposition from a sulfamate bath.The codeposition behavior of Ni-Co alloy coating in the initial stage of electro crystallization and electrochemical reaction process were investigated by means of cathodic linear scanning and chronoamperometry test,and the nucleation model of Ni-Co alloy coating was discussed.The surface morphology and microstructure of Ni-Co alloy coating were characterized by scanning electron microscope and X-ray diffraction.The thermal stability of Ni-Co alloy coating was investigated by microhardness test after annealing.The results showed that the deposition potential of Ni-Co alloy coating was about-0.73 V,and the nucleation and growth process for Ni-Co alloy coating was closer to the instantaneous nucleation model with diffusion controlled mechanism.Ni-Co alloy coating exhibited dense surface with small grains,and good thermal stability.