【摘要】 在硅酸盐体系中,利用单相脉冲微弧氧化技术在Mg-5wt%Li合金表面原位生长陶瓷膜.利用扫描电镜、X射线衍射、电化学分析、盐水浸泡等方法研究了陶瓷膜的形貌特征、相结构及耐腐蚀性能.结果表明:硅酸盐电解液体系中生长的陶瓷膜主要含有MgO相和少量的MgSiO3相,微弧氧化陶瓷膜试样与基体相比,耐点腐蚀性能显著提高,盐水浸泡过程中陶瓷膜主要发生严重腐蚀.通过正交试验优化耐蚀膜层的制备工艺条件,得到最佳工艺为电流密度2A/dm2、频率300Hz、占空比80%、处理时间20min.更多还原

【Abstract】 Micro-arc oxidation (MAO) coatings were in-situ fabricated on the surface of Mg -5wt% Li alloy in a sodium silicate solution system by a home-made pulsed mono-polar electrical source. The morphology feature,phase composition and corrosion-resistance properties of ceramic coatings were studied by SEM,XRD, electrochemical method and salt water corrosion tests respectively. The results showed that the coatings are composed of MgO and MgSiO3. The coated samples have much better pitting corrosion resistance than the Mg-Li substrate in terms of cyclic voltammetry curves. Samples the coated samples had severe corrosion in the salt water. The optimum current denstiy,frequency,adjusting ratio and reaction time were 2 A/dm2,300 Hz, 80% and 20 min respectively.更多还原