摘要
用Gleeble-1500热模拟实验机测定了FB钢变形后的CCT曲线,并对实验钢采用不同工艺进行了控轧控冷实验。研究了工艺参数对实验钢力学性能和组织的影响,分析了FB钢的强韧化机制。实验表明,实验钢在较宽的冷却速度范围(大于2℃/s)内可获得贝氏体组织。降低终轧温度可使铁素体晶粒得到细化;提高开冷温度,可使贝氏体体积分数增加,抗拉强度升高;而卷取温度则对屈服强度影响较明显。合理的控轧控冷工艺可使实验钢的强度级别达到600MPa,并具有较高的韧、塑性、扩孔性和合理的屈强比。扩孔实验表明,细化晶粒可提高扩孔率,贝氏体体积分数在20%左右时实验钢扩孔性能较好。
The continuous cooling transformation curves with deformation of ferrite/bainite（FB） steel were studied by Gleeble--1500 thermal mechanical simulation. Controlled rolling and controlled cooling were carried out using different schedules. Effect of technological parameters on the mechanical properties and mierostructure were investigated, and strengthening mechanisms of FB steel were analyzed. Thermal simulation results showed that bainite structure could be obtained at a wide cooling rate above 2℃/s. The mierostructure could be refined by reducing finish rolling temperature and increasing start cooling temperature. So that the strength increasing of the experimental steel follows the volume fraction increasing of bainite. However coiling temperature has great influence on yield strength. Experimental steel with 600MPa, good ductility, plasticity, hole flangeability and yield ratio can be obtained by the proper TMCP technology. The experiment of hole flanging revealed that the rate of hole flanging could be increased by refining the grain size,and the experimental steel has good hole flanging when the volume content of bainite is about 20 %.
出处
《轧钢》
2008年第3期16-21,共6页
Steel Rolling
关键词
FB钢
CCT曲线
控轧控冷
力学性能
扩孔
FB steel
CCT curve
controlled rolling and controlled cooling
mechanical properties
hole flanging
