耐候钢锈层及其稳定化处理现状

 耐候钢具有良好的耐大气腐蚀性,但是稳定化锈层形成较慢,在耐候钢使用前对表面进行预处理,可以缩短锈层稳定化形成时间和防止锈液流挂。简要概述了国内外耐候钢的发展情况,以及耐候钢稳定化锈层的形成过程和锈层的组成与结构,分为以γ-FeOOH为主的疏松外锈层和以α-FeOOH为主的致密内锈层;介绍了表面锈层保护机理,包括物理阻隔、阳极钝化保护、缓蚀剂保护和离子选择性渗透保护;为了探究耐候钢最佳使用方式,综述了当前耐候钢的使用方法,主要分为裸露、涂装以及锈层稳定化处理后使用,提出了耐候钢锈层稳定化处理的技术要点,即选择合适的成膜材料和促进α-FeOOH形成的促进剂,并展望了今后锈层稳定化处理技术应用和发展方向。

Rust layer of weathering steel and its stabilization treatment status

Weathering steel has good atmospheric corrosion resistance,but the formation of stable rust layer is slow.Pretreatment of the surface of weathering steel before use can shorten the formation time of rust layer stabilization and prevent rust liquid from sagging.The development of weathering steel at home and abroad,the formation process of stabilized rust layer and the composition and structure of rust layer are briefly summarized.The rust layer is divided into loose outer rust layer dominated byγ-FeOOH and dense inner rust layer dominated byα-FeOOH.The mechanism of rust layer protection is introduced,including physical barrier,anodic passivation protection,corrosion inhibitor protection and ion selective penetration protection.In order to explore the best use of weathering steel,the current application methods of weathering steel are summarized,which are mainly used after exposed,coated and rust stabilized.The key points of stabilizing treatment for rust layer of weathering steel are put forward,that is,selecting suitable film forming materials and accelerants to promote the formation ofα-FeOOH.The application and development direction of stabilization treatment technology in the future are prospected.