建筑用耐火钢的研究现状及发展趋势

摘要

Fire-resistant steel is the first choice of green steel materials of construction steel structure. Composition design of different ideas through the production of iron and steel enterprises abroad have developed fire-resistant steel at different grades, especially has been great developed and widely used in high-rise building construction. China also conducted research and development, and the performance reached a considerable level with foreign fire-resistant steel, but less application. The reason is that the traditional fire-resistant steel contains high Mo content, alloy cost is much higher than ordinary construction steel. Fire-resistant steel should possess a lot of bainite to ensure high strength at elevated temperature, but bainite is the microstructure transformed at middle temperature, which is difficult to control by TMCP process, and that is difficulty to develop. The development of economic fire-resistant steel with low Mo content, high strength, well tougthness, and replace ordinary construction steel + fire-resistant coating, is one of the development trend of the steel structure of modern architecture.%耐火钢是建筑钢结构的首选绿色钢铁材料。国外钢铁生产企业通过不同的成分设计思路相继开发了不同级别的耐火钢，并已大量应用于高层建筑。国内也进行了研究开发，且性能达到与国外耐火钢相当的水平，但是应用业绩较少，其原因是传统耐火钢Mo含量高，合金成本远高于普通建筑用钢。耐火钢必须通过一定量的贝氏体以保证良好的高温性能，而贝氏体属中温转变组织，对轧制及冷却工艺要求高，是耐火钢开发的难点。开发低Mo含量的低成本、高强度、高韧性耐火钢，并逐渐取代普通建筑钢+耐火涂层，是现代建筑钢结构的发展趋势之一。