低屈强比590/780MPa建筑用钢DL-T工艺研究  

Study on DL-T Technology of Low Yield Ratio 590/780MPa Steels for Construction

作　　者：唐帅[1] 刘振宇[1] 王国栋[1] 

机构地区：[1]东北大学轧制技术及连轧自动化国家重点实验室,辽宁沈阳110004

出　　处：《轧钢》2010年第1期6-10,共5页Steel Rolling

基　　金：国家"863"项目(2007AA03Z504);十一五国家科技支撑计划项目(2006BAE03A08)

摘　　要：采用Nb-V-Ti低成本成分设计及两相区直接淬火回火(DL-T)工艺,在实验室成功开发了低屈强比590/780MPa高强度建筑用钢。实验结果表明,直接淬火温度在750℃以下时可以得到一定量的铁素体,满足低屈强比双相组织的要求;在600～750℃直接淬火时,随着直接淬火温度的升高,钢板强度增加,伸长率降低;在600～700℃淬火时屈强比基本保持不变,当淬火温度升高到750℃时,组织中的铁素体和贝氏体共同对屈服强度产生影响,造成屈强比由0.76上升到0.82。Through proper chemical composition design,the low yield ratio 590/780MPa steels for construction were successfully developed in laboratory with direct lamellarizing-tempering（DL-T）technology.The effect of lamellarizing temperature on microstructure and mechanical properties of this steel was studied.The results indicated that there were some content ferrite when the direct lamellarizing below 750℃,and the dual-phase structure can be obtained.The yield strength and tensile strength increased but the elongation decreased as the direct lamellarizing temperature increased at 600～750℃.Yield ratio remained constant as the direct lamellarizing temperature ranged from 600 to 700℃.However,when the direct lamellarizing temperature increased to 750℃,both ferrite and bainite affected the yield strength,which resulted in the yield ratio raising from 0.76 to 0.82.

关 键 词：建筑用钢 两相区直接淬火 低屈强比 组织 

分 类 号：TG162[金属学及工艺—热处理]