返红温度对低屈强比高强度耐火耐候钢组织及性能的影响  

Effect of self-tempering temperature on microstructure and properties of high strength fire-resistant and weathering construction steel with low yield ratio

作　　者：林田子 侯华兴 杨颖 张涛 张哲 纪汶伯 Lin Tianzi;Hou Huaxing;Yang Ying;Zhang Tao;Zhang Zhe;Ji Wenbo(Iron&Steel Research Institutes of Ansteel Group Corporation,,Anshan Liaoning 114009,China)

机构地区：[1]鞍钢集团钢铁研究院,辽宁鞍山114009

出　　处：《金属热处理》2020年第6期39-43,共5页Heat Treatment of Metals

基　　金：国家重点研发计划(2017YFB0304700)。

摘　　要：采用光学显微镜(OM)、扫描电镜(SEM)、透射电镜(TEM)等方法对不同返红温度下的低屈强比高强度耐火耐候钢的微观组织及力学性能进行了研究与分析。结果表明:当钢板水冷后的返红温度从550℃下降至350℃时,试验钢显微组织由铁素体和少量贝氏体逐渐转变为由板条贝氏体和弥散细小的M-A岛组成的复相组织结构,贝氏体板条尺寸进一步细化,钢板的屈服强度、屈强比明显升高,抗拉强度变化不大,断后伸长率降低。在返红温度为450~500℃范围内试验钢具有较低的屈强比和更优异的强韧性匹配。Microstructure and properties of high strength fire-resistant and weathering construction steel with low yield ratio at different selftempering temperatures were studied by OM,SEM and TEM.The results show that when the self-tempering temperature of the steel plate after water cooling is decreased from 550℃to 350℃,the microstructure of the tested steel gradually changes from ferrite and a small amount of bainite to multiphase structure consisting of lath bainite and dispersed fine M-A islands.The size of bainite lath is further refined,the yield strength and yield ratio of the steel plate increase obviously,the tensile strength does not change much,and the percentage elongation after fracture decreases.When the self-tempering temperature is within the range of 450-500℃,the tested steel has lower yield ratio and better strength-toughness matching.

关 键 词：高强度耐火耐候钢 返红温度 组织 性能 低屈强比 

分 类 号：TG142.1[一般工业技术—材料科学与工程]