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目的：采用含颗粒电解液是目前最常用制备具有更佳性能微弧氧化膜层的方法之一，主要研究微弧氧化过程中颗粒掺杂与电源模式的关系。方法在Y2 O3颗粒质量浓度为0~10 g/L的电解液中，分别以单极脉冲和双极脉冲电源模式制备一系列微弧氧化膜层，并从表面形貌、表面元素组成、截面形貌及耐蚀性能等方面对膜层进行综合评价。结果分散在电解液中的颗粒带有负电荷，在微弧氧化过程中发生电泳现象。在单极脉冲电源模式下，颗粒受正电吸引而发生定向迁移，在试样附近聚集并且吸附至表面，从而参与下一步的微弧氧化膜层形成过程。随着电解液中颗粒浓度的提高，分散在微弧氧化膜层表面的Y2 O3颗粒数量增多，膜层表面的Y元素含量增加，膜层变得致密，耐蚀性能因而提高。在双极脉冲电源作用下，由于电场的交替变化，颗粒难以聚集在试样周围，颗粒的掺杂只能通过随机熔融包覆进行，因而参与到微弧氧化过程中的颗粒数量较少。结论颗粒掺杂受电场力影响，在单极脉冲模式下，颗粒的掺杂浓度对膜层的性能影响明显；在双极脉冲电源模式下，负向电流的引入不利于颗粒掺杂至氧化膜层，颗粒的掺杂浓度对膜层的性能影响不明显。

ABSTRACT:Objective Particles-containing electrolytes are commonly employed as one of the most important methods to produce better micro arc oxidation coatings. The relationship between the MAO coating property and power mode used was described in this paper. Methods Ceramic coatings were produced by micro arc oxidation in electrolyte containing various particles concentration in unipolar and bipolar power mode, respectively. The properties of coatings were evaluated in respect of surface morphologies, ele-mentary distribution, cross-section morphologies, and corrosion resistance. Results The particles dispersed in electrolyte were nega-tively charged, and particles-doping during MAO process was driven by electrophoresis. Particles were directly migrated to the anode in unipolar power mode, accumulating around the sample and adsorbed to the sample surface to participate in the formation process of the micro arc oxidation coatings. With increasing particles concentration in electrolyte, the amount of Y2 O3 particles and the con-tent of Y element on the surface of the MAO coatings increased, enhancing the density and corrosion resistance of the coatings. However, only a few particles doped in MAO coating as the power mode turned to bipolar due to alternate variations of electric field. The influences of particles concentration on the surface and cross-section morphologies, surface elementary distribution, cor-rosion resistance of MAO coatings were not apparent. Conclusion Particles-doping was affected by electric force. In unipolar power mode, the doping concentration of particles had obvious effect on the performance of the coatings, whereas in the bipolar power mode, introduction of negative current had adverse effect on the doping of particles into the oxidation coatings, and the doping con-centration of particles had no obvious effect on the coating performance.