微弧氧化提高铝合金耐磨性能的研究

目的改善铝合金的综合性能,尤其是耐磨性。方法采用微弧氧化技术,在铝合金表面制备具有自润滑效果的微弧氧化陶瓷膜层。通过分析电解参数(电流密度、频级和能级)对微弧氧化陶瓷膜耐磨性的影响,以及添加剂石墨对陶瓷膜厚度、表面形貌、相组成、耐磨性和耐蚀性的影响,探索可以提高铝合金表面微弧氧化陶瓷膜综合性能的电解参数,研究石墨在铝合金微弧氧化中所起的作用。结果确定了最佳电解参数。添加剂石墨不仅降低了铝合金陶瓷膜的摩擦系数,同时也提高了铝合金的耐蚀性。结论在铝合金微弧氧化中,石墨的自润滑特性和超高的导电性促进了铝合金在微弧氧化过程中成膜反应的进行,增加了陶瓷膜层的厚度,同时对试样表面有光滑、整平的作用。

Improving the Wear Resistance of Aluminum Alloy through the Micro-arc Oxidation Technology

Objective To improve the comprehensive performance of aluminum alloy, especially the wear resistance. Methods Self-lubricating ceramic layers were prepared by the micro-arc oxidation technology on the surface of aluminum alloy. The electrolytic parameters for improving the comprehensive performance of the micro-arc oxidized ceramic membrane on the aluminum alloy and the role of graphite in the micro-arc oxidation of aluminum alloy were explored by analyzing the effects of electrolytic parameters (current density, frequency ratio, energy level ratio) on the wear resistance of the micro-arc oxidized ceramic membrane and the influences of graphite addition on the thickness of ceramic membrane, surface morphology, phase composition, wear resistance and corrosion resistance. Results The optimal electrolytic parameters were determined. Graphite addition could not only decrease the friction coefficient of the micro-arc oxidized ceramic membrane on the aluminum alloy, but also improve the corrosion resistance of aluminum alloy. Conclusion With self-lubricating property and ultrahigh electric conductivity, graphite could promote the membrane forming reaction during the micro-arc oxidation of aluminum alloy, increase the thickness of the ceramic layer and smooth the surface morphology of the as-obtained aluminum alloy.