中文摘要：

对540MPa级铁素体/贝氏体双相钢的组织性能进行分析研究。结果表明,试验钢的显微组织为85%左右的铁素体加上15%左右的贝氏体;铁素体晶粒尺寸细小,基体中有较高的位错密度和大量细小弥散的析出物;贝氏体在铁素体基体上分布均匀,以板条状为主,板条间分布有较多碳化物颗粒。通过合适的成分设计和控轧控冷手段获得的铁素体/贝氏体双相钢组织形态,可较好地保证材料所需的强度-拉伸凸缘性能匹配。

英文摘要：

The mechanical properties and microstructure of 540 MPa grade ferrite/bainite dual-phase steel were investigated.The results show that the tested steel is made up of about 85% ferrite and 15% bainite.The fine grain ferrite has high dislocation density and massive fine precipitates.The bainite is mainly lathy with many carbide articles and distributes among ferrite equably.This dual-phase microstructure obtained by appropriate chemical composition design and TMCP guarantees the required strength and stretch-flangeability of the material.