| Aluminum bronze alloys which have high strength, excellent plasticity, wear and corrosion resistance and so on have been successfully applied to stretching and pressing tools. In order to widen its application in surface engineering, this paper discussed the self-lubricate aluminum bronze (Cu-14Al-X) powder which was made by nitrogen atomization. The main composition of the powder is: Cu 70 ~ 80%, Al 12 ~16%, Fe 2.0 ~ 4.0% and the rest is other microelements, for example, Mn, Co, Ni and Re.Two kinds of self-lubricate aluminum bronze coatings on AISI-1045 steel were respectively prepared by plasma spraying and laser cladding technology. By using X-ray diffraction (XRD), scanning electron microscopy (SEM), electron probe micro-analyzer (EPMA), field emission scanning electron microscopy (FESEM), energy dispersive spectrometer (EDS) and friction and wear test machine, microstructure, forming process, interface between substrate and coating, bonding strength, macrohardness, microhardness and friction and wear properties were studied. The effect of different particle size of powder on them was also analysed. Finally, surface treatment technology fitting to self-lubricate aluminum bronze (Cu-14Al-X) coating was gained. The results showed different preparing technologies has different influences on morphology, composition and hardness. 1. The phases of the two coatings are same, includingα,γ2,β? and K. The structure of laser cladding coating is finer, denser without clear grain boundaries and the hard K phases disperse in the substrate, While those in the plasma spraying coating is large and distributes unevenly. 2. The element contents of them are different, especially Fe. The content Fe in plasma spraying coating is up to 11.30%, while that in laser cladding coating is only 3.83%. 3. The hardness of laser cladding coating which is 362.5HV is higher than that of plasma spraying coating which is only 304HV. 4. The effect of different particle size of powders on properties of the plasma spraying coating is obvious.Friction and wear properties of plasma spraying coating and laser cladding coating were performed on RFT-III friction and wear test machine under boundary lubricant condition. The results are as follows: 1. Friction and wear mechanism of the two coatings is various. That of the plasma spraying coating is slight abrasive abrasion under low load, while serious adhesion abrasion under high load with slight abrasive abrasion. That of laser cladding coating is mainly abrasive abrasion. 2. Plasma spraying coating possesses excellent wear resistance under low load, but wear loss and friction coefficient increase violently under high load, which illustrates its tribological properties is less stable than that of the laser cladding coating.In the same test conditions, tribological properties of laser cladding coating, plasma spraying coating and Cu-14Al-X alloys were studied. 1. The wear mechanism of laser cladding coating and Cu-14Al-X alloys is mainly abrasive abrasion, but plasma spraying coating is adhesion abrasion. 2. Tribological performance of plasma spraying coating under low load is better than that of Cu-14Al-X alloys and laser cladding coating, but under high load, wear resistance decreased rapidly, which indicates its tribological stability is not good. 3. Laser cladding coating and Cu-14Al-X alloys have similar tribological properties, but wear loss of laser cladding coating is slightly higher than that of Cu-14Al-X alloys. Friction stability of laser cladding coating is better than that of Cu-14Al-X alloys.The structure of the self-lubricate aluminum bronze coatings with and without Ce is same. Adding moderate Ce can refine the structure, change the morphology, size of the K phases, increase their quantities and make them disturb more evenly. Ce can also restrain segregation of alloy elements and accelerate atomic diffusion which is benefit for alloying, thus form dense fusing zone.
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