铌微合金化控冷工艺生产HRB500抗震钢筋强韧化机理  

Strengthening and toughening mechanism of HRB500 anti-seismic rebars with Nb microalloyed and controlled cooling process

作　　者：陈伟[1,2] 施哲[1] 赵宇[2] 

机构地区：[1]昆明理工大学冶金与能源工程学院,云南昆明650093 [2]武钢集团昆明钢铁股份有限公司技术中心,云南昆明650302

出　　处：《中南大学学报（自然科学版）》2011年第6期1604-1610,共7页Journal of Central South University:Science and Technology

基　　金：云南省科技计划项目(2009BA008)

摘　　要：采用Nb微合金化和控冷工艺开发HRB500抗震钢筋,通过金相显微镜、扫描电镜、透射电镜、X线衍射仪及拉力试验机对钢筋取样金相显微组织、析出相、力学性能及强韧化机理进行分析研究。研究结果表明：采用Nb微合金化和控轧控冷工艺生产HRB500抗震钢筋,最主要的强化机制为细晶强化,其对强度贡献超过40%;采用该工艺,钢筋铁素体晶粒度达11.0级以上,晶粒细化效果明显;铁素体基体、晶界及位错线上形成和分布着尺寸为10~20 nm的大量细小弥散的Nb（CN）析出相,起到了较好的沉淀强化及细化晶粒作用;晶粒细化使冲击转折温度下降150℃,使钢筋在获得较高强度的同时,仍具有较好的塑韧性。Development of HRB500 anti-seismic rebars by Nb microalloyed and controlled cooling process was introduced.The microstructure,educt,mechanical properties,strengthening and toughening mechanism were researched and analyzed by means of metallographic microscopy,scanning electron microcopy,transmission electron microscopy,X-ray diffraction apparatus and tensile testing machine.The results show that fine-grain strengthening is the primary mechanism of strengthening and toughening for HRB500 rebars produced by Nb microalloyed and controlled cooling process,contribution of its strength is more than 40% of total strength;ferrite grain grade of rebars is more than 11.0,obvious effect of grain refinement is obtained.A large number of small and diffuse of Nb（CN） educts sized 10-20 nm are formed and distributed on ferrite matrix,grain boundary and dislocation lines,good effect of precipitation strengthening and grain refinement are received;impact transition of temperature reduces by 150 ℃ by grain refinement,and higher strength for rebars is acquired.Meanwhile,rebars still have good plasticity and toughness.

关 键 词：HRB500抗震钢筋 细晶强化 Nb(CN) 沉淀强化 塑韧性 

分 类 号：TF762.3[冶金工程—钢铁冶金] TG142.4[一般工业技术—材料科学与工程]