富氮钒铌微合金化控冷工艺制备600MPa级抗震钢筋应用研究  

Application Research on Preparation of 600MPa Grade Anti-seismic Rebars by Nitrogen-rich,Nb-V Microalloyed and Controlled Cooling Technology

作　　者：陈伟[1] 张卫强[1] 吴光耀 赵宇[1] 张瑜[1] 

机构地区：[1]武钢集团昆明钢铁股份有限公司技术中心,云南昆明650302 [2]玉溪新兴钢铁有限公司,云南玉溪653106

出　　处：《热加工工艺》2017年第4期95-100,共6页Hot Working Technology

摘　　要：采用拉力试验机、金相显微镜、透射电镜、X射线衍射仪、扫描电镜和冲击试验机对富氮钒铌微合金化控冷工艺制备的600MPa级抗震钢筋的力学性能、显微组织、析出相、断口形貌、冲击韧性及时效性进行了研究。结果表明:该钢筋具有良好的强韧性、抗震性及低应变时效性,力学性能优异。该钢的显微组织为铁素体+珠光体+少量细小贝氏体(含量5%~10%),组织配比及形态较好。该钢的铁素体基体、晶界及位错线上析出了大量尺寸2~20nm的细小弥散的V(CN)、Nb(CN)析出相,其析出相数量分别占总钒、总铌量的65%以上,起到了较好的沉淀强化及细化晶粒作用。该钢筋拉伸断口呈韧窝状,韧脆转变温度低于-30℃,具有较好的塑韧性和低温冲击韧性。The mechanical properties, microstructure, precipitates, SEM micrographs of tensile fracture, impact toughness and aging property of 600 MPa grade anti-seismic rebars prepared by nitrogen-rich- Nb-V microalloyed controlled cooling technology were analyzed by using tensile testing machine, metallographic microscopy, transmission electron microscopy,X-ray diffraction apparatus, scaning electron microcopy and impact testing machine. The results show that the rebars have better strength-toughness performance, good aseismicity properties and low strain aging, and the mechanical properties are optimal. The microstructure of the tested rebars consists of ferrite, pearlite and a small amount of fine bainite（5%-10%）, the ratio of microstructure and shape are better; a large number of small and diffuse V（CN） and Nb（CN） with the size of 2-20 nm precipitate on ferrite matrix, grain boundary and dislocation lines. The fraction of V（CN） and Nb（CN） precipitate is more than65% of total amount of vanadium and niobium, respectively, which can play a better role in precipitation strengthening and grain refinement. The tensile fracture of the rebars is dimple and the ductile-brittle convert temperature is lower than-30 ℃,then the rebar has good plasticity-toughness and low temperature impact toughness.

关 键 词：富氮钒铌微合金化 控冷工艺 600MPa级抗震钢筋 力学性能 析出相 冲击韧性 

分 类 号：TG113.2[金属学及工艺—物理冶金] TG142.1[金属学及工艺—金属学]