(1. 河海大學(xué) 機(jī)電工程學(xué)院，常州 213022；2. 江蘇鴻業(yè)涂料科技產(chǎn)業(yè)有限公司，常州 213016)
摘 要: 研究鎂合金微弧氧化(PEO)陶瓷層表面的電泳成膜機(jī)理；分析工藝參數(shù)對(duì)復(fù)合膜層耐蝕性的影響。采用掃描電鏡、示波器和鹽霧試驗(yàn)機(jī)等分別研究復(fù)合膜層的表面和截面形貌、電泳過(guò)程中電流變化規(guī)律及腐蝕防護(hù)性能。結(jié)果表明：在電泳成膜過(guò)程中，微弧氧化陶瓷層微孔處被擊穿，電泳回路產(chǎn)生電流，電泳漆帶電粒子先在微孔處沉積，然后向周?chē)苿?dòng)并沉積，當(dāng)電流降為0時(shí)，電泳過(guò)程結(jié)束。隨著陶瓷層厚度和粗糙度的增加，陶瓷層被擊穿時(shí)間延長(zhǎng)，電泳漆粒子沉積時(shí)間縮短。微弧氧化陶瓷層的腐蝕速率是微弧氧化/電泳涂裝復(fù)合膜層的6.286倍，說(shuō)明鎂合金微弧氧化陶瓷層經(jīng)電泳處理后，其耐蝕性得到了顯著的增強(qiáng)。
關(guān)鍵字: 鎂合金；微弧氧化；電泳沉積；成膜機(jī)理
deposited organic layer on PEO film of magnesium alloy
（1. College of Mechanical and Electrical Engineering, Hohai University, Changzhou 213022, China;
2. Jiangsu Hongye Coatings Co., Ltd., Changzhou 213016, China）
Abstract:The formation mechanism of organic layer within ceramic layer by the electrophoretic deposition (EPD) was investigated. The influence of processing parameters on the corrosion resistance of the composite coating was analyzed. The surface and cross-section morphologies, variation of current in the EPD and corrosion protection were evaluated using scanning electron microscope, oscilloscope and salt spray tester, respectively. The results indicate that the breakthrough and current appears in the EPD process. As a result, the charged particles in electrophoretic paint are firstly deposited within micropores on the ceramic layer, and then spread out. When the current of the EPD becomes 0, the electrophoretic deposition is completed. A long time for breakthrough and a reduction for the EPD time occur with the increase of the thickness and roughness of the ceramic layer. The corrosion rate of the PEO coating is 6.286 times as fast as that of the composite coating. This is of practical significance for magnesium alloys in the formation of organic layer within ceramic layer to improve corrosion resistance.
Key words: magnesium alloy; plasma electrolytic oxide; electrophoretic deposition; formation mechanism
