TC4合金表面微弧氧化膜层耐蚀及摩擦性能研究

Wear and Corrosion Resistance Properties of TC4 Alloy Micro-Arc Oxidized Coating

利用微弧氧化技术,硅酸钠、磷酸钠溶液体系,在TC4合金表面制备出硬度高、耐磨性好的陶瓷膜层。采用SEM,XRD分析了膜层的形貌特征和成分及相结构。在H2SO4及HCl溶液中的腐蚀研究表明,涂层腐蚀速率是基体的1/9;在3.5%NaCl溶液中进行极化曲线及交流阻抗测试,表明陶瓷膜层自腐蚀电位由基体的-0.29V提高到0.45V,腐蚀电流提高1个数量级,耐蚀性提高1个数量级;耐磨试验研究表明,膜层的摩擦系数为0.39,大于基体的0.28;摩擦40min情况下,膜层耐磨性能很好。

Ceramic coatings were fabricated on TC4 alloy by micro-arc oxidation method in silicate solution with high and good wear resistance. Its microstructure and phase composition were characterized by scanning electron microscope （SEM） and X-ray diffraction （XRD）. The uniform corrosion resistance of the coated samples in H2SO4 and HCl was improved by nine times, compared with the TC4 substrate. Besides, polarization curve and alternating current impedance test in 3.5% NaCl solution show that the coating has better corrosion resistance. Tribotest at 5 kg load show that the coating has the friction coefficient of 0.39, which is higher than 0.28 of substrate, and better wear resistant, after 40 min.