摘要
针对酒钢CSP线,设计了600 MPa级热轧双相钢的化学成分,测定了其动态CCT曲线。根据动态CCT曲线,分别采用三段式与两段式冷却模式进行了现场试制,对试制热轧板进行了显微组织观察与力学性能检测。结果表明:通过化学成分的合理设计及关键工艺参数的合理控制,热轧板的显微组织为铁素体+马氏体,屈服强度均达到325 MPa以上,抗拉强度均达到600 MPa以上,屈强比为0.53~0.58,伸长率均达到26.9%以上,并且其应力-应变曲线为连续屈服。两段式与三段式冷却模式都可使热轧板的综合性能达到了DP600热轧双相钢的性能指标。虽然两段式冷却模式在工艺上控制简单、更易于实现,但二段式冷却模式得到的屈服强度偏低;采用三段式冷却模式,并将一段快冷结束温度控制在700℃左右,可得到相对较高的屈服强度,使热轧板的综合性能更佳。
For the JISCO's CSP line,the chemical composition of hot-rolled dual phase steel of 600 MPa grade was designed.The CCT curve of the test steel was measured.According to the dynamic CCT,the three-stage and two-stage cooling modes were used for on-site trial production,and the microstructure and mechanical properties of the trial-produced hot-rolled sheets were examined.The results show that the microstructure of the hot-rolled sheets are ferrite and martensite by reasonable control of the chemical composition and key process parameters,the yield strength,tensile strength and ductility of DP600 are more than 325 MPa,600 MPa,and 26.9%,respectively,and yield ratio is 0.53~0.58.The stress-strain curve is continuous and has no yield point.The properties of hot rolled plates by the cooling models of two-stage and three-stage can also meet the performance requirements of DP600 hot rolled duplex steel.Although the cooling mode of two-stage is easy to control in the process,but the yield strength of plates is low.The relatively high yield strength and better comprehensive performance of hot rolled plates can be obtained adopting the cooling model of three-stage,meanwhile the temperature at the end of the first stage of rapid cooling is controlled at about 700℃.
作者
杨华
吝理平
王云平
成洋洋
刘靖
YANG Hua;LIN Li-ping;WANG Yun-ping;CHENG Yang-yang;LIU Jing(Gansu Jiugang Hongxing Iron and Steel Co.Ltd.,Jiayuguan 735000,China;School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China)
出处
《甘肃冶金》
2021年第1期53-57,61,共6页
Gansu Metallurgy
关键词
CSP短流程生产线
热轧双相钢
动态CCT曲线
冷却模式
组织性能
compact thin slab production line
hot-rolled dual phase steel
dynamic CCT curve
cooling mode
microstructure and properties
