Study On The Electrodeposition Process And Properties Of Ni And CNTs/Ni Films

Composite electrodeposition can be prepared thin film of20microns to180microns.Metal can also be deposited to the surface of carbon nanotubes, and one-dimensionalcomposite material is obtained. These techniques can be applied in electronic computer field,such as nano sensors and recording head.This paper introduces the method of electrodeposition and composite electrodepositionon the surface of pure Al to prepare pure Ni and CNTs/Ni film, and characterize themorphology, structure and performance of electrodeposition and co-electrodeposition filmwith SEM, XRD, microhardness tester and DMA. The paper discusses the relation betweenstructure and performance of film and electrodeposition condition such as pH value, currentdensity and concentration of CNTs. This thesis also researches the rule of Ni and CNTs/Nifilm growth.Experimental results show that the current density and electrolyte pH had a greaterinfluence on the morphology and properties of thin film. When current density is less than1A/dm~2, grain is very small, otherwise, as the current density increased, the massive equiaxialgrain grows larger. With the increase of current density,(200) crystal plane of preferredorientation tend to be stronger gradually. As pH value is5.5, particle grains change intostrips, grain orientation also changes into (111) crystal plane. At the pH value of5.0, pure Nifilm has largest tensile and strength. As pH value is4.5, pure Ni film has largest hardness.Analysis shows that the deposition rate is approximately proportional to current density.But with the increase of current density, double-sided electrodeposition films have differentthickness. CNTs/Ni composite coating has fine grain and CNTs are disperse in it.Butcomposite film has low strength cause its loose surface. On the condition of1.25g/L can getthe maximum hardness of composite film, microhardness is257HV,15%more than pure Nicoating.