摘要
运用ＭＥＴ、ＳＥＭ、ＥＰＭＡ等手段观察６０６３铝型材在工业阳极氧化预处理的碱洗过程中表面所出现的过腐蚀形貌，同时对腐蚀产物的成分进行分析，找出产生这种过腐蚀的原因，并对其形成机理进行了探讨．结果表明，腐蚀区是由密集的择优沿挤压方向分布的点蚀坑构成；蚀坑中腐蚀残留物主要是游离Ｓｉ和Ａｌ－Ｆｅ－Ｓｉ等阴极性粒子．研究认为，腐蚀是因偏聚的阴极性粒子（游离Ｓｉ，Ａｌ－Ｆｅ－Ｓｉ）周围阳极区的优先溶解所致．同时还发现Ｃｅ、Ｆｅ、Ｚｎ等元素以其不同的方式促进腐蚀的发生、发展．
By means of MET,SEM and EPMA,overcorrosion morphology on the surface of 6063 aluminum extrusion,which often appears during the caustic washing process of pretreatment of anodizing,was observed ,and corrosion products were examined. Overcorrosion mechanism was also studied. The results demonstrated that corrosion area was composed of densed pittings which are mainly along the direction of extrusion,and that corrosion products in the pittings are cathodic particles such as free silicon and Al Fe Si.It is considered that prefe rential dissolution of anodic area around these cathodic particles leads to localized corrosion. It is also found that chlorine、zinc and ferrum could promote the occurrence and the development of corrosion in different patterns.
出处
《腐蚀科学与防护技术》
CAS
CSCD
1998年第1期28-32,共5页
Corrosion Science and Protection Technology
关键词
铝型材
阳极氧化
过腐蚀
aluminum extrusion, anodizing, overcorrosion
