使用Ni与纳米Cr颗粒共沉积方法制备Ni--Cr纳米复合镀层, 研究了镀液中Cr颗粒浓度、搅拌强度和阴极电流密度等工艺参数对镀层中沉积Cr量的影响. 结果表明: 镀层中纳米Cr颗粒的复合改变了电沉积Ni的生长方向, Ni晶粒由原来沿(200)晶面取向生长, 转变为沿(200)、(111)和(220)晶面均匀生长. 镀层中Cr复合量越多, Ni晶粒的形核位置越多, Ni晶粒越细化. 也探讨了Ni--Cr纳米复合镀的沉积机理.
Novel Ni--Cr nanocomposite coatings were fabricated by composite electrodeposition of Ni and Cr nanoparticles from a nickel sulfate bath. The influence of the Cr contents in nanocomposite film was investigated by changing Cr concentration in electrolyte bath, agitation rate and current density. Surface morphologies and microstructure of Ni--Cr coatings were observed by means of SEM / EDAX, TEM and XRD. It was found that the codeposition of Cr nanoparticles disturbed the crystal growth of the nickel matrix, leading to a change from the preferential Ni on (200) planes to the homogeneous growth on (200), (111) and (220) planes. This demonstrated that the nanoparticles codeposition promoted the nucleation of new nickel grains. The more the content of the Cr nanoparticles codeposited, the finer the electrodeposited Ni matrix. Meanwhile, the electrodeposition mechanism of the Ni--Cr nanocomposite system was discussed.