Na_2WO_4和SiC_p对2A12铝合金微弧氧化膜的影响

Effects of Na_2WO_4 and SiC_p on Micro-arc Oxidation Coatings on 2A12 Aluminum Alloy

在质量浓度为40g/L的Na2SiO3,8g/L的Na2WO4混合电解液中添加SiCp,在2A12铝合金基体上原位生长微弧氧化陶瓷膜。采用扫描电子显微镜(SEM)、能谱分析仪(EDS)、X射线衍射仪(XRD)分析了陶瓷膜微观形貌、元素含量、相组成,通过数字式覆层测厚仪和摩擦磨损试验检测了氧化膜的厚度和耐磨性。结果表明,Na2SiO3、Na2WO4混合电解液生长的陶瓷膜由α-Al2O3和mullite相组成,膜层较致密,Na2WO4的加入提高了膜层生长速率;添加SiC微粒后,微弧氧化过程中SiC微粒分解,促进莫来石相形成,膜层有较好的耐磨性。

Ceramic oxide coatings were prepared on 2A12 aluminum alloy by micro arc oxidation in 40 g/L Na2SO3 and 8 g/L Na2WO4 mixed electrolyte with SiC particle addition.Micro-morphology,phase constituent and chemical composition of the coating were analyzed by SEM(scanning electron microscope),EDS(energy dispersive spectrometer),XRD(X-ray diffraction).Thickness and wear resistance of the coating were measured by the digital thickness meter and friction wear testing.The results show that the coating consists of α-Al2O3 and mullite phase in Na2SiO3 and Na2WO4 electrolyte,and Na2WO4 can promote compact growth of the coating.SiC particle is decomposed in the process of microarc oxidation,promoting the formation of mullite phase.The coatings ware preferable abrasive resistance.