780MPa级低屈强比高层建筑用钢的生产工艺研究

来源期刊：钢铁2010年第7期

论文作者：康健 王昭东 王国栋 袁国 周晓光

文章页码：71 - 75

关键词：建筑用钢； 低屈强比； 超快冷； 复相组织

Key words：constructional steel； low yield ratio； ultra-fast cooling technology； composite microstructure

摘    要：对高强度低屈强比建筑用钢进行了实验室生产研究。通过适当的成分设计,利用两阶段的控制轧制及超快冷技术对试验钢的组织进行控制以达到提高强度、降低屈强比的目的。结果表明:终轧后立即冷却到690℃左右后空冷至室温,可以得到具有贝氏体铁素体软相基体、体积分数为9.2%的M/A组元作硬质第二相的复相组织,其屈服强度与抗拉强度均满足780 MPa级相关要求,同时屈强比在0.7左右。

Abstract: Steel plate for buildings with high strength and low yield ratio was studied in laboratory.The microstructure of test steel was controlled by proper composition design,controlled rolling and UFC technology in order to increase strength and decrease yield ratio.It has been shown that the composite microstructure of soft phase(bainite ferrite) and hard phase(M/A) can be obtained when UFC final cooling temperature was about 690 ℃,and the percentage of M/A component is about 9.2%.The yield strength and tensile strength could meet the requirements of 780 MPa grade,and the yield ratio was about 0.7.