| Aluminum alloys are widely used in many areas because of a series of excellent properties.However the development of aluminum alloy is restricted because of the poor wear resistance.So the surface treatment of aluminum alloys becomes the key to expand the scope of using and prolonging service life.Micro-arc oxidation is a new surface treatment technology.A ceramic coating of high hardness,corrosion resistance and wear resistance can be gotten on the surface of aluminum alloys.The research is based on LY12,using low voltage MAO technology to get compact and self-lubricating coatings on the surface of aluminum alloy quickly by adding solid lubricating particles on electrolyte.This solved the poor friction property on the surface on the coatings.Using SEM and XRD observe the surface morphology of coatings and analysis the phase composition of coatings.Analysis the friction property of coatings by friction experiment.The results show that:(1)By using simulation software FLUENT,we obtained the best stirring speed 200r/min.(2)The relationship between processing parameters(concentration of electrolyte,voltage,temperature of electrolyte,BN consistence)and coating BN content are nonlinear.The relationship between coating BN content,fraction time and friction coefficient are nonlinear.(3)The coating is made up of a-Al2O3??-Al2O3 and BN mainly.The result shows that the particles of BN on electrolyte into the coatings and obtained the self-lubricating coatings.(4)The optimum parameters are KF consistence 105g/L,KOH consistence 85g/L,NaAlO2 consistence 12g/L,voltage 110V,treatment temperature 40?,BN consistence 10g/L,treatment time 15min.This study successfully prepared self-lubricating coatings and the optimum coating BN content was determined 10vol%and the fraction coefficient lowered to 0.173.The particles of BN distribute uniformly in the coating and have the self-lubricating function.The friction property of the compound coating was improved effectively. |
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