中文摘要：

采用轧后空冷＋超快速冷却工艺，研究卷取温度对热轧铁素体／贝氏体（F／B）双相钢组织性能的影响规律．结果表明：卷取温度由504℃降至250℃时，铁素体体积分数变化很小（85．7％-87．8％），铁素体晶粒尺寸变化也很小（3．6-3．7μm），组织中的硬相由以贝氏体为主转变为以马氏体为主；实验钢的抗拉强度由510MPa升至597MPa，屈服强度由475MPa降至389MPa，延伸率变化较小（32．2％～35．0％）．另外，随着卷取温度的降低，铁素体与贝氏体或马氏体间的变形协调能力降低，使扩孔过程中微孔提前形核，同时加快了已有微孔的长大及合并过程，导致试样发生的塑性变形减小，扩孔性能降低，扩孔率由101．4％降至52．4％．

英文摘要：

The process of air-cooling followed by ultra fast cooling after hot-rolling was used to investigate the effects of coiling temperature on the microstructure and mechanical properties of a ferrite/bainite （F/B） dual phase steel. The results show that the volume fraction and the grain size of ferrite are in the rage of 85.7% - 87.8% and 3.6 - 3.7 μm, respectively, almost independent of the coiling temperature. Lowering coiling temperature from 504 ℃to 250 ℃, the dominant hard phase was transformed from bainite to martensite, resulting in the ultimate strength up to 597 MPa from 510 MPa, the yield strength down to 389 MPa from 475 MPa, but the elongation without significant change （32. 2% -35. 0% ）. Besides, the deformation compatibility between ferrite and bainite or martensite is weakened with the decrease of the coiling temperature, which induces the nucleation in advance, accelerates growth and coalescence of micro-voids, so the hole expansion property is deteriorated and the hole expansion ratio is reduced from 101.4% to 52. 4%.