SiC纳米颗粒对TA2微弧氧化涂层组织结构及耐蚀性能的影响机制

The Influence of SiC Nanoparticles on the Microstructure and Corrosion Behavior of Microarc Oxidation Coatings Formed on TA2 Alloy

摘要:

为提高钛及钛合金防腐蚀、耐磨损等关键服役性能,本研究在TA2钛合金表面制备微弧氧化陶瓷涂层,研究纳米SiC颗粒的添加对微弧氧化涂层组织结构及耐蚀性能的影响机制.结果表明,基础电解液中SiC的加入能够大幅度提高TA2微弧氧化涂层的厚度,且随着电压的升高,涂层的厚度和表面粗糙度也随之增大,涂层表面的微孔尺寸随着电压的升高而逐渐增大,SiC的加入能够有效地抑制微弧氧化涂层表面裂纹的产生；微弧氧化涂层的物相主要有高温稳定相金红石及锐钛矿,还含有少量的SiC及SiO2；微弧氧化涂层增加TA2的开路电位及自腐蚀电位,随着处理电压的增加开路电位随着升高；SiC的加入降低了涂层的阳极电流密度,显著提高了微弧氧化涂层得耐蚀性能。

Abstract:

In order to improve the anti-corrosion and anti-wear properties of titanium alloy, a microarc oxidation (MAO) coating was fabricated on the surface of TA2 alloy. The influences of SiC nanoparticles on the microstructure and corrosion behavior of MAO coatings were investigated. The results showed that the introduction of SiC nanoparticles into the base electrolyte increased the coating thickness of MAO coating. The thickness, surface roughness and micropore size of the coating increased with the increasing applied voltage. The microcracks in the coating was decreased by SiC particles. The phase composition of coatings consisted of rutile phase, anatase phase, SiC and SiO2. The OCP and corrosion potential was increased by MAO treatment. The introduction of SiC nanoparticles decreased the anodic current density, and thus increased the corrosion property of the alloy.