Preparation the Ni/W coating on 6061 aluminium alloy surface using laser remelting and high voltage cathodic deposition techniques

Abstract

Cathodic deposition (CD) is a material preparation and surface modification technique which is based on the electrolytic principle of reducing a layer of metal, alloy or compound on the cathodic substrate surface. However, the CD technique is only applicable to non-valved metals. In this paper, we firstly use laser remelting (LR) technology to change the morphology of the valve metal 6061 aluminium alloy surface, and then use CD technology to treat the valve metal 6061 aluminium alloy surface. This method solved the problem of not being able to use CD technology on valve metal 6061 aluminum alloy and prepared a Ni/W coating on the surface of valve metal 6061 aluminum alloy. Energy dispersive spectroscopy (EDS)/X-ray diffraction (XRD)/Scanning electron microscopy (SEM) was used to characterize the micro-morphology and elemental composition of the prepared coatings. The friction and corrosion properties were tested by friction and corrosion experiments. The results show that the coating obtained after LR and CD has the advantages of high hardness, large thickness, good wear resistance, small friction coefficient and good corrosion resistance. By using LR technology for pre-treatment makes CD technology directly usable on the valve metal surface, which is of great significance for subsequent applications.