On significance of initial microstructure in governing mechanical behavior and fracture of dual-phase steels
On significance of initial microstructure in governing mechanical behavior and fracture of dual-phase steels作者机构：State Key Laboratory of Rolling and AutomationNortheastern University Shenyang 110819 Liaoning China Laboratory for Excellence in Advanced Steel ResearchUniversity of Texas El Paso TX 79968 USA
出 版 物：《Journal of Iron and Steel Research International》 (国际钢铁研究杂志)
年 卷 期：2018年第25卷第9期
页 面：932-942页
核心收录：
学科分类：08[工学] 081402[工学-结构工程] 081304[工学-建筑技术科学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0813[工学-建筑学] 0814[工学-土木工程]
主 题：Dual-phase steel Microstructure Mechanical property Strain-hardening Fracture
摘 要：Different initial microstructures were obtained through combination of intercritical annealing and cold-rolling. Subsequently, steels with different microstructures of ferrite-pearlite （FP）, ferrite-martensite （FM） and complete martensite （M） were intercritically annealed at 780 ℃ for 5 min and water quenched to obtain ferrite-martensite microstructure. The significance of initial microstructures on ultimate microstructure, mechanical properties, strain-hardening ability and fracture behavior in dual-phase steels has been elucidated. Initial microstructures of FP, FM and M yielded different martensite morphologies, notably chain-like network structure, fine and fibrous martensite structure, respectively. Furthermore, with increasing martensite content in the initial microstructure, the average grain size of ferrite was significantly refined from about 12.3 to 2.1 μm, which results in that the ultimate tensile strength （UTS） and yield strength were increased, total elongation remained unaffected, and uniform elongation （UE） and strain-hardening ability were increased. A comparison of mechanical properties for different initial microstructures suggested that when the initial microstructure was complete martensite, the steel had excellent mechanical properties, with UTS × UE of 122.5 J cm^-3, which was 24% greater than the conventional continuously annealed steels with ferrite-pearlite initial microstructure （98.8 J cm^-3）. The variation in tensile properties, strain-hardening ability and fracture mechanism of steels with different initial microstructures were discussed in relation to the ultimate microstructures.
维普期刊数据库