显微组织对桥梁钢在模拟海洋潮差区腐蚀行为的影响.pdfVIP

显微组织对桥梁钢在模拟海洋潮差区腐蚀行为的影响 李 琳 徐小连 陈义庆 钟 彬 艾芳芳 高 鹏 （鞍钢股份有限公司技术中心，鞍山 114009 ） 摘 要 为考查不同显微组织的桥梁钢在模拟海洋潮差区环境下的腐蚀行为，采用不同热处理工艺的桥梁钢进行周 期浸润加速腐蚀试验。采用电化学法、失重分析、腐蚀产物的相组成分析研究其腐蚀演化规律。结果表明：试样经 过回火处理后，由粒状贝氏体非平衡组织向回火索氏体平衡组织转变，并且晶粒细化、组织更为均匀，因此在模拟 海洋潮差区环境下回火索氏体组织的耐海水腐蚀性能好于粒状贝氏体组织的耐海水腐蚀性能。经过 640℃回火处理 的 试样，碳化物颗粒弥散并且细小，其耐腐蚀性能较好。周期浸润试验中的锈层起到了对基体的保护作用，轧态 试样粒状贝氏体组织的外锈层中 FeOOH 的α/γ 比较低、内锈层的α-Fe 较高，说明粒状贝氏体组织的锈层保护性较 差。 关键词 周期浸润 耐腐蚀性能 显微组织 锈层 Effect of Microstructure on Corrosion Behavior of Bridge Steels under Simulated Ocean Tide Zone Li Lin Xu Xiaolian Chen Yiqing Zhong Bin Ai Fangfang Gao Peng （Technology Center of Angang Steel Co ．，Ltd ．，Anshan ，114009） Abstract To investigate the corrosion behavior of bridge steels with different microstructure under simulated ocean tide zone, the bridge steels with different heat treatment processes were used for alternate immersion accelerated corrosion test. The rusting evolution of bridge steels was studied by electrochemical method, weight-loss method and corrosion product analyses. The results showed that the microstructure of the samples was changed from non-equilibrium granular bainite to equilibrium temper sorbite after drawing temper. Because of the grain refinement and uniformity of structure, corrosion resistance of temper sorbite microstructure was better than granular bainite microstructure in simulated ocean tide zone. As carbide grain was dispersion and fine, the seawater corrosion resistance of sample tempering at 640℃ was best in simulated ocean tide zone. The rust layer formed through alternated immersion test provided protection for the substrate steels. Because the outer rust layer α/γ of hot rolled sample with granular bainite microstructu