(北京科技大學表面科學與腐蝕工程系，北京 100083)
摘 要: 研究了合金中鋅含量對6063鋁合金型材在陽極氧化前表面預處理過程中發(fā) 生雪花狀腐蝕的影響。結(jié)果表明，當合金中鋅含量高于0.063%時，型材易發(fā)生雪花 狀腐蝕，鋅含量低于0.046%時， 型材一般不發(fā)生雪花狀腐蝕。利用EPMA對表面進行成分分析發(fā)現(xiàn)，在堿洗過程中，鋅含量較高的型材表面出現(xiàn)鋅富集現(xiàn)象。這是因為合金中鋅元素在堿洗過程中， 由于溶解與再沉積作用， 在型材表面富集，從而使合金表面電化學性質(zhì)不均勻，造成堿洗不均勻， 引發(fā)雪花狀腐蝕。
關(guān)鍵字: 6063鋁合金 局部腐蝕 陽極氧化 堿洗
（Department of Surface Science and Corrosion Engineering, University of Science and Technology Beijing, Beijing 100083, P. R. China）
Abstract:One common corrosion is known as "galvanizing" in the pretreatment process of 6063 alloy for anodizing. The effects of zinc content in the alloy on "galvanizing" were studied. The results show that the "galvanizing" only appear on the 6063 alloy which contains zinc of more than 0.05%. EPMA analysis indicates that zinc segregates on the 6063 alloy with higher zinc content during etching in caustic soda solution. This phenomenon may result from the dissolution of zinc in the bath and then its reprecipitation on the surface of the alloy in the etching process.
Key words: 6063 alloy localized corrosion anodizing etching
