| Electrodeposition lubricating coating can be propitious to improve the wear-resistant and corrosion resistance of metal surface. Poor working conditions in oil or some special requirements of the lubrication system for lubricating oil can not be supplied sufficiently, this coating will show a great deal of the superiority. Most of self-lubricating particles are conductive particles, such as MoS2, graphite, etc. And when conductive particles were adhesion on the cathode surface, the surface of coating becomes more rough and even the formation of dendritic crystallization, which may be caused by cutting-edge effects.In this paper, insulating material was coated onto MoS2 particles by particle surface modification technology. Research and optimization of coating process, observation of surface morphology of coated particles. Ni-based lubricant coating containing coated particles of MOS2/Al2O3 was preparated by composite plating, which avoiding dendritic crystallization caused of the coating by the conductivity of MoS2 particles. Study on impact of dispersing agent on the of particles scattered in the solution. Research process of composite plating with coated particles and the optimization of best process parameters. The deposition model of of coated particles during composite plating was established. Distribution of coated particles in the coating was investigated. Observation of surface morphology of coatings and analysis of structural changes by XRD. Study on bonding strength, microhardness, friction and wear properties and corrosion resistance of coating.In this paper, surface texturing was prepared by electrolysis. Surface texturing with various dimensions and densities were generated in material surfaces, by means of changing the exposed area, current density and electrolysis time. Electrodeposited lubricating coating was prepared in porous of surface texturing, which is the preparation of surface texturing Ag-MoS2/Al2O3 lubricating coating. Friction and wear performance of surface texturing Ag-MoS2/Al2O3 lubricating coating and GCr15 steel mates ring/disc were estimates. And the effect of texturing parameters, such as diameter and density on tribological properties of estimates was also tested. Lubricated friction and wear-resistant of surface texturing Ag-MoS2/Al2O3 lubricating coating and surface texturing MoS2 dry film lubricant were studied comparativly.Process parameters of MoS2 particles were coated with PS or Al2O3 was studied, the optimum process parameters for MoS2 particles coated with Al2O3 was temperature of 80℃, pH value of 7.0 and the range of Al3+ concentration is 0.1～0.25mol/l. Under the conditions of optimization process parameters can be prepared uniformly Al2O3 coating on MoS2. Uniform coated, non-agglomeration PS/MoS2 particles was prepared, the optimum process parameters for MoS2 particles coated with PS was:0.2wt% AIBN (based on the mass fraction of styrene monomer), polymerization time 2h, the amount of styrene monomer and the ratio for particles with 1ml:10g, styrene monomer was added under intense stirring slowly.In this paper, self-lubricating composite coating was prepared by sediment co-deposition technique. The effect of dispersant on dispersion of particles in the plating bath have been studied. The experimental results show that: the dispersion of particles in solution of 0.4mg/l CTAB is superior to OP-10 and sodium dodecyl sulfate. The proeess parameters affecting the particles contents in composite coatings were investigated, the optimum proeess parameters were chosen: particle concentration in the plating bath:25g/l, current density:11A/dm2, stirring speed: 600rpm, pH value:4.5, temperature:55℃. The effect of coated particles or non-coated particles on the coating properties has been studied. Content of coated particles in the coating were higher than those of non-coated particles under the same conditions. Coating that emboded by non-coated conductive particles appeared dendritic organization. While coating that emboded by coated particles are to avoid the appearance of the dendritic organization and provided with uniformity surface morphology. Binding force of Gradient composite coating is superior to those of even the composite coating, coated particles in the coating was distributed uniformity.Friction and wear and corrosion resistance of composite coating were studied. And the mechanism of wear-resistant and anti-corrosion has been studied too, the results showed that: friction coefficient of Ni-PS/MoS2 coating is lower than those of Ni-MoS2 coating; but friction coefficient of Ni-MoS2/Al2O3 coating is higher than those of Ni-MoS2 coating. The friction coefficient of these composite coatings are decreasing with the increasing of particle content in bath. Image microscopy of worn scar was observed by SEM and optical microscope. Change of components on worn scar was analysed by EDS and XPS. The results show that:the lubricating film formed on the surface of worn scar. Transfer lubricating film formed on the surface of ceramic ball. Coating that emboded with particles coated with PS or Al2O3 possess of good corrosion resistance. Which is due to the corrosion potential of composite coating increased, while the corrosion current decreases, when was corroded in the same corrosion medium.The results show that: the friction and wear properties of surface texturing Ag-MoS2/Al2O3 lubricating coating were better than those of surface texturing MoS2 dry film lubricant and the smooth surface. The sample with dimples of 500μm in diameter and 500μm in clearance has a optimal tribological performance. Mechanism of friction and wear of surface texturing 2/Al2O3 lubricating coating was investigated. |
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