纳米TiO2微粒对2214铝合金微弧氧化膜微观结构及耐磨性能的影响

摘要

2214 aluminum alloy was treated by micro-arc oxidation in the silicate system electrolyte with different concentra-tions of nano TiO2 particles and the MAO composite coatings containing TiO2 were prepared on 2214 aluminum alloy.The micro-structure,surface roughness,phase composition,hardness,adhesion strength and wear resistance of MAO composite coatings were analyzed by SEM,EDS,laser confocal microscope,XRD,Vickers hardness tester,scratch tester and ball-on-disc abrasive tester, respectively.The results revealed that the MAO composite coatings were mainly composed of γ-Al2O3,α-Al2O3,mullite,anatase-TiO2 and rutile-TiO2.With the increasing content of TiO2 microparticles in the electrolyte,the size and number of pores on MAO composite coatings surface decreased significantly.Compared to the MAO coatings without TiO2,the MAO composite coatings ex-hibited better wear resistance as demonstrated by the lower friction coefficient and the lower wear rate.%在含有不同浓度纳米TiO2微粒的硅酸盐体系电解液中对2214铝合金进行微弧氧化处理,以在2214铝合金表面制备包含TiO2的复合陶瓷膜.分别使用 SEM、EDS、激光共聚焦显微镜、XRD、维氏硬度计、划痕仪和球盘式摩擦磨损试验机对复合陶瓷膜的微观结构、表面粗糙度、相成分、硬度、粘结强度、耐磨性能进行分析.结果表明:复合陶瓷膜主要由γ-Al2O3、α-Al2O3、莫来石、锐钛矿型TiO2和金红石型TiO2组成,且随着电解液中TiO2微粒浓度的增加,复合陶瓷膜表面的微孔数量显著减少,微孔尺寸显著减小.与不含TiO2成分的微弧氧化陶瓷膜相比,复合陶瓷膜通过更低的摩擦系数和更小的磨损率展示了更好的耐磨性能.