Study On Preparation And Properties Of Cu-AlN With High Performance Coating By Electrodeposition

In this paper,the manufacture technology and current study of electrodeposited composite coatings were introduced.Composite coating of Cu-nano AlN was prepared. Effects of different parameters on the composite coatings were researched by orthogonal test method and single factor analysis method. The metallographic microscope, the scanning electron microscope(SEM), the X-ray diffraction(XRD) were used in the analysis on the morphology of surface, microstructure and the composition of Cu-AlN composite coatings. The microhardness test, the friction wear test and the electrochemistry experiment were measured on the properties of mechanical behavior, the friction and wear behavior, corrosion resistance.The results show that: the addition of AlN and current density is the most important factor affecting coating performance, with the added amount of AlN increased the hardness and wear resistance of composite coatings increased gradually, as to 15g / l , the composite coating to achieve the best overall performance, when aluminum nitride added more than 15g / l, the coating's overall performance. When the cathode current density of 4 A/dm2, the composite coating corrosion resistance and wear the best, after the cathodic current density increases with the coating of the integrated performance.In the compound of the deposition process, Cu and nano-AlN reaction do not occur between the new phase. Matrix composite coatings are polycrystalline Cu, and fine grain size composite coating, structure uniform and compact. AlN nano-particles have good dispersibility in the matrix of the composite coating showed uniform dispersedHardness analysis show that: With the increase of adding amount of aluminum nitride, the hardness gradually decreased, when the dosage of aluminum nitride 15g / l, the composite hardness is maximum, while the hardness value than pure copper high 100HV.Corrosion resistence test show that: Cu-AlN composite coating friction surface after the experiment is more smooth, friction shallow furrow formation and sparse, while the copper coating on both sides of the furrows to accumulate, resulting in significant plastic deformation. Composite coating, the wear volume and wear only the amount of copper plating of 1 / 4, Cu-AlN composite coating was superior wear resistance to pure copper coating.Thermal conductivity analysis show that: the coating thermal conductivity and did not significantly lower than pure copper, and aluminum nitride added content is the main factor affecting thermal conductivity. When the AlN concentration of 15g / l, the coating thermal conductivity maximum, when the AlN concentration higher than 15g / l, the thermal conductivity decreased sharply, reaching 84W/mk.ZETA potential of the bath showed that: nano composite coating is superior to aluminum nitride aluminum nitride composite coating micron. When the aluminum nitride particle size to 15nm, the Zeta potential of the bath reaches the maximum, this time the surface of positively charged particles rise to the highest deposition rate at this time, then composite coating for minimum wear.This paper analyzes the AlN nano-and micron AlN properties of the coating, results show that: nano-particles after modification, the nano-composite coating in the deposition rate, hardness, wear resistance and thermal conductivity of the composite than micron coating is greatly improved. Nanocomposite coating is superior to micron composite...