纳米ZrO2微粒对TC4合金表面微弧氧化陶瓷膜层耐蚀及耐磨性能的影响

Effect of Nano-ZrO2 Particles on Corrosive and Abrasive Performances of the Micro-arc Oxidized Ceramic Film on TC4 Alloy Surface

目的提高TC4微弧氧化表面陶瓷涂层的耐蚀性与耐磨性,并研究ZrO2微粒对涂层性能的影响。方法在不同配比的硅酸钠、磷酸钠、氢氧化钠混合电解液中,通过微弧氧化技术在TC4钛合金表面制备陶瓷涂层,得到最佳电解液配比。将纳米ZrO2微粒添加到电解液中,以制备复合涂层。通过SEM、XRD、电化学工作站以及往复摩擦磨损试验机,研究不同含量ZrO2对膜层的形貌、相结构、耐腐蚀及耐磨性的影响。结果随着纳米ZrO2浓度的增加,涂层微孔数量和尺寸都减小,膜层的主要组成相为ZrO2、ZrTiO4、TiO2、Ti2O、Al2O3和SiO2。0.9%NaCl溶液中的电化学极化曲线表明,随着ZrO2浓度的增加,涂层的自腐蚀电位不断提高,但当添加剂的含量达到12g/L时,自腐蚀电位降低。摩擦磨损实验显示,不含ZrO2陶瓷膜层的比磨损率为1.082×10^-3mm^3/(N·m),当ZrO2含量为9g/L时,其比磨损率为3.489×10^-4mm^3/(N·m),是未添加颗粒的32.24%。结论纳米ZrO2微粒的加入有效提高了陶瓷涂层的耐蚀、耐磨性,特别地,当添加量为9g/L时,涂层的耐蚀性耐磨性最好。

The work aims to improve the wear and corrosion resistance of micro-arc oxidation ceramic coatings on the surface of TC4 and study the effects of ZrO2 on coating performance.In mixed electrolyte of Na2SiO3,Na3PO4 and NaOH with different concentrations,the micro-arc oxidation coating was fabricated on the surface of TC4 by micro-arc oxidation (MAO) technology to obtain the optimum electrolyte ration.The Nano-particles ZrO2 were added into electrolyte to fabricate composite coating.The effects of ZrO2 concentration on the morphology,phase structure,corrosion resistance and wear resistance of the film were analyzed by scanning electron microscope (SEM),X-ray diffraction (XRD),electrochemical workstation and friction- abrasion testing machine.The friction and wear test was carried out under dry friction.The quantity and size of the micro-pores decreased with the increase of the ZrO2 concentration.The coatings were mainly composed of ZrO2,ZrTiO4,TiO2, Ti2O,Al2O3 and SiO2.The electrochemical tests in 0.9% NaCl solution showed that the self-corrosion potential of coatings improved with the increase of ZrO2 concentration.However when the ZrO2 concentration reached 12 g/L,the corrosion potential was decreased.The friction and wear experiments showed that the specific wear rate of ceramic coating without ZrO2 particles was 1.082×10^-3 mm^3/(N·m).When the content of ZrO2 was 9 g/L,the specific wear rate was 3.489×10^-4 mm^3/(N·m),accounting for 32.24% of that of coatings without ZrO2 particles.The addition of ZrO2 particles can effectively improve the corrosion resistance and abrasion resistance of the ceramic coating.In particular,the coating has the best corrosion resistance and wear resistance when the concentration of added particles is 9 g/L.