(1. 江蘇科技大學(xué) 材料科學(xué)與工程學(xué)院，鎮(zhèn)江 212003；
2. 江蘇科技大學(xué) 檔案館，鎮(zhèn)江 212003)
摘 要: 在自主研制的鋁酸鈉-磷酸鈉復(fù)合電解液體系中，采用不同的正向電壓(220~340 V)對(duì)ZK60變形鎂合金進(jìn)行微弧氧化，在鎂合金表面制備陶瓷膜層。利用掃描電鏡、超景深光學(xué)顯微鏡及能譜儀觀察分析膜層組織，通過(guò)電流變化及放電現(xiàn)象分析微弧氧化過(guò)程，并用全浸實(shí)驗(yàn)和電化學(xué)阻抗法測(cè)試膜層在3.5% NaCl(質(zhì)量分?jǐn)?shù))介質(zhì)中的耐腐蝕性能。結(jié)果表明：電流平穩(wěn)階段是膜層的主要生長(zhǎng)階段，正向電壓是微弧氧化過(guò)程的重要驅(qū)動(dòng)力，電壓過(guò)高或過(guò)低都不利于獲得優(yōu)質(zhì)膜層。280 V正向電壓下制備的膜層組織較為均勻致密，其腐蝕速率較低，為0.2054 g/(m2？h)，此時(shí)膜層電化學(xué)阻抗模值為正向電壓340 V下膜層的3倍。
關(guān)鍵字: ZK60鎂合金；微弧氧化；正向電壓；耐腐蝕性
（1. School of Materials Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, China;
2. Archives, Jiangsu University of Science and Technology, Zhenjiang 212003, China）
Abstract:Micro-arc oxidation (MAO) process was conducted on ZK60 Mg alloy in a self-made aluminate-phosphate dual electrolyte system containing aluminate and phosphate with positive voltage from 220 to 340 V. A MAO coating was prepared on the surface of ZK60 Mg alloy. The microstructure characteristics of coatings were investigated by scanning electron microscope (SEM), super depth of field microscope and energy dispersive spectrometer (DSC). The process evolution was evaluated through current change and electric discharge phenomena. The corrosion resistance of coatings was measured in 3.5% NaCl (mass fraction) solution by immersion test and electrochemical impedance spectroscope (EIS). The results show that the main growth of coating takes place in stable current stage and positive voltage is an important driving force for better MAO coating. A uniform and compact MAO coating can be obtained under certain suitable positive voltage. The MAO coating prepared at 280 V exhibits good corrosion resistance with corrosion rate of 0.2054 g/(m2？h), and its impedance value is as 3 times as that of coating made at 340 V.
Key words: ZK60 Mg alloy; micro-arc oxidation; positive voltage; corrosion resistance
