(北京航空航天大學 材料科學與工程學院 空天材料與服役教育部重點實驗室,北京 100191)
摘 要: 在原位鋯溶膠和外加鋯溶膠的磷酸鹽電解液體系中,采用恒流模式對鋁合金進行微弧氧化,通過分析氧化過程中電壓和電解液參數(shù)的變化、氧化膜生長規(guī)律以及膜層表面形貌結(jié)構(gòu),研究鋯溶膠對鋁合金微弧氧化成膜過程的影響。結(jié)果表明,原位鋯溶膠電解液氧化過程中pH值降低及電導率增加幅度較小,起弧電壓、電解液溫度較低,膜層生長速率較快,其厚度增長速率約為2.9 μm/min。原位鋯溶膠電解液制備的膜層表面呈多孔網(wǎng)狀結(jié)構(gòu),內(nèi)外膜層結(jié)合緊密,膜層較厚,可達85 μm;外加鋯溶膠電解液生成膜層表面有火山狀沉積物,膜層疏松;微弧氧化膜主要由γ-Al2O3和t-ZrO2相組成。
關(guān)鍵字: 鋁合金;鋯溶膠;微弧氧化
(Key Laboratory of Aerospace Materials and Performance, Ministry of Education,
School of Materials Science and Engineering, Beihang University, Beijing 100191, China)
Abstract:Aluminum alloy was processed by microarc oxidation method with a control mode of constant current density in phosphate electrolyte with in-situ and additional zirconia sol. The effects of zirconia sol on the microarc oxidation process were investigated. The variations of voltage and electrolyte parameters, the growth process and surface microstructure of coatings were analyzed. The results indicate that in the electrolyte with in-situ zirconia sol, pH values reduce less, conductivity increases less, arcing voltage and electrolyte temperature are lower, and the growth rate of coating is higher, which is about 2.9 μm/min. The ceramic layer obtained in electrolyte with in-situ zirconia sol is porous, the internal and external layers combine closely, the coating is thicker and the thickness is up to 85 μm. The ceramic layer prepared in the electrolyte with additional sol includes more volcano-like deposits and is loose. The ceramic layer is mainly composed of γ-Al2O3 and t-ZrO2 phases.
Key words: aluminum alloy; zirconia sol; microarc oxidation


