460MPa级耐火耐候建筑用钢的组织和性能研究
Study on Microstructure and Properties of 460 MPa Grade Fire and Weather Resistant Building Steel
裘韶均 1闫江辉 1唐辉 1赵彦灵 1张志慧 2张鹏程 2武会宾2
作者信息
- 1. 宁波钢铁有限公司,浙江 宁波 315807
- 2. 北京科技大学 钢铁共性技术协同创新中心,北京 100083
- 折叠
摘要
采用低钼复合添加钛、镍、铬、铜的微合金化设计,配以合理的控轧控冷工艺,试制了低成本 460 MPa级耐火耐候建筑用钢.通过周浸实验研究了实验钢在模拟工业大气环境中的耐候性能.结果表明:实验钢由粒状贝氏体、M/A岛耐火钢理想组织组成.在 600℃保温时析出的大量纳米级Ti的碳氮化物,纳米析出物与位错发生交互作用,阻碍位错运动,提高了实验钢的高温力学性能.与Q345B钢相比,耐火耐候建筑用钢的耐蚀性能提升了 30%以上.耐火耐候建筑用钢的锈层致密且稳定,锈层中的α-FeOOH含量较多,能有效阻止腐蚀离子接触基体.腐蚀速率及稳定锈蚀相的相对含量变化证明了耐火耐候建筑用钢锈层随时间延长变得越来越稳定,耐候性能更好.
Abstract
Low-cost 460MPa grade fire-resistant and weather resistant building steel was successfully developed by using a low molybdenum microalloying design with the addition of titanium,nickel,chromium and copper and a reasonable controlled rolling and cooling process.The weatherability of the experimental steel in simulated industrial atmosphere was studied by salt spray and peripheral immersion experiments.The results show that the experimental steel is composed of granular bainite and ideal microstructure of M/A-island refractory steel.A large number of nano Ti carbonitrides precipitated at 600℃can interact with dislocations,hinder the movement of dislocations and improve the high temperature mechanical properties of the experimental steel.Compared with that of Q345B steel,the corrosion resistance of fire-resistant and weather resistant building steel improves by more than 30%.The rust layer of fire-resistant and weather resistant building steel is dense and stable,and that has high content of α-FeOOH,which can effectively prevent the corrosive ions from contacting the matrix.The change of corrosion rate and relative content of stable corrosion phase proves that the rust layer of fire-resistant and weather resistant building steel becomes more and more stable with time,and the weather resistance is better.
关键词
耐火耐候钢/高温性能/耐候性/周浸/锈层Key words
fire-resistant and weathering steel/high temperature performance/weather resistance/peripheral immersion/rust layer引用本文复制引用
基金项目
国家重点研发计划项目(2021YFB3701700)
出版年
2024
NETL
NSTL
万方数据