镁基封闭型ZrO2陶瓷膜成膜机理及腐蚀行为研究

The application of MgO ceramic coating formed by micro-arc oxidation is considered to be limited in anticorrosion due to their microstructure and composition. Therefore, in this project, the sealing ZrO2 coating was produced on magnesium alloy by micro-arc oxidation in external electric field from alkaline zirconate with negatively charged Zr(OH)4. The influence of size of Zr(OH)4, external electric-field intensity and electric parameters of micro-arc oxidation during the sealing processing on the pore structure and efficiency of sealing were confirmed. Moreover, the geometric locus and precipitation as well as morphometry of Zr(OH)4 under external electric field were comprehensively researched to reveal the film formation mechanism and corrosion behavior of sealing ZrO2 micro-arc oxidation coated on magnesium alloy, which may reinforce the primary micro-arc oxidation processing theory and extend the applied field of magnesium alloy.

镁合金表面微弧氧化MgO多孔陶瓷膜因其成分和结构的特点，易于被腐蚀，需要改善陶瓷膜成分或进行封孔工艺。本项目采用外加电场与微弧氧化处理相结合的方法，在碱性锆盐电解液中利用带负电荷的Zr(OH)4溶胶一次性完成陶瓷膜的制备和封孔，形成封闭型ZrO2陶瓷膜。项目针对氧化封孔过程中，Zr(OH)4溶胶尺寸、外加电场强度及微弧氧化电参数对封孔效率、陶瓷膜孔内结构的规律性影响展开基础研究。通过建立孔隙率、溶胶尺寸及电场参数之间的规律性关系，确定Zr(OH)4溶胶在电场下的运动轨迹；以此为依据，讨论溶胶在陶瓷膜微孔中的沉积过程、脱水形成ZrO2的形态及对腐蚀行为的影响；最终揭示封闭型ZrO2陶瓷膜的成膜机制及抗腐蚀机理。本项目研究可明确自封闭型微弧氧化ZrO2陶瓷膜形成过程及影响因素，揭示成膜机理。通过研究陶瓷膜的耐蚀性，探索本方法的科学性和实践性，为改善陶瓷膜的组织、结构及性能提供新途径和理论基础。

镁合金表面微弧氧化MgO多孔陶瓷膜因其成分和结构的特点，易于被腐蚀，需要改善陶瓷膜成分或进行封孔工艺。本项目采用了外加电场与微弧氧化处理相结合的方法，在碱性锆盐电解液中利用带负电荷的Zr(OH)4溶胶一次性完成了陶瓷膜的制备和封孔，形成了封闭型ZrO2陶瓷膜。项目针对氧化封孔过程中，Zr(OH)4溶胶尺寸、外加电场强度及微弧氧化电参数对封孔效率、陶瓷膜孔内结构的规律性影响展开了基础研究。通过建立孔隙率、溶胶尺寸及电场参数之间的规律性关系，确定了Zr(OH)4溶胶在电场下的运动轨迹；以此为依据，讨论了溶胶在陶瓷膜微孔中的沉积过程、脱水形成ZrO2的形态及对腐蚀行为的影响；最终揭示了封闭型ZrO2陶瓷膜的成膜机制及抗腐蚀机理。