Transactions of Materials and Heat Treatment

Title：Influence of finishing rolling temperature on microstructure and property for hot-rolled dual phase steel DP580

Authors： Guo Zifeng Zhang Yan Li Qiuhan Guo Jia Feng Jun Li Yupeng Lyu Baofeng

Unit： Shougang Research Institute of Technology Beijing Key Laboratory of Green Recyclable Process for Iron & steel Production Technology Beijing Shougang Co. Ltd.

KeyWords： hot-rolled dual phase steel ferrite martensite mechanical property fatigue property

ClassificationCode：TG335.35

year,vol(issue):pagenumber：2019,44(6):188-192

Abstract：

For shougang hot-rolled dual phase steel DP580, the influences of two typical finishing rolling temperatures on its microstructure, tensile properties and fatigue properties were studied by optical microscope, fatigue testing machine, tensile testing machine and others. The results show that the grain size of ferrite, content and morphology of martensite significantly change at different finishing rolling temperatures. When the finishing rolling temperature increases, the grain size of ferrite significantly increases, and the martensite is island-shaped with the high volume fraction, the irregular shape and the multiple corners. However, when the finishing rolling temperature decreases, the grain size of ferrite is smaller and the content of ferrite is higher, and the martensite is diffuse and uniformly distributed. Comparing with the mechanical properties shows that the yield strength of DP580 steel varies obviously with the different finishing rolling temperatures, and the larger size of ferrite results in the lower yield strength when the finishing rolling temperature is higher. Comparing with the S-N curves,it shows that the fatigue life of DP580 steel is lower when the finishing rolling temperature is higher. Thus, the ferrite with large size and the island-shaped martensite with multiple corners and irregular shape accelerate the initiation and expansion of cracks.

Funds：

首钢科技项目（2018科1-5）

郭子峰（1984-），男，博士，高级工程师 E-mail：guozifeng5588@163.com

Reference：

［1］王利，杨雄飞，陆匠心. 汽车轻量化用高强度钢板的发展
［J］. 钢铁, 2006, 41 (9): 1-8.

Wang L, Yang X F, Lu J X, Development of high strength steel sheets for lightweight automobile
［J］. Iron & Steel, 2006, 41 (9): 1-8.

［2］Naoko S, Yoshitaka A, Hiroyuki K，et al, Topological approach to ferrite/martensite dual-phase microstructures
［J］. ISIJ Int., 2012, 52 (7)：1362-1365.

［3］Furukawa T，Tanino M I，Morikawa H,et al. Effects of composition and processing factors on the mechanical properties of as-hot-rolled dual-phase steel
［J］. Trans. ISIJ, 1984, 24(2): 113-121.

［4］Murugaiyan A，Saha A，Pandit A．Phase transformations in two C-Mn-Si-Cr dual phase steels
［J］．ISIJ Int.，2006，46(10)：1489-1494.

［5］宋义全，阎振.Si-Mn-Cr型热轧双相钢相变和组织的研究
［J］. 钢铁, 1995, 30(12): 51-54.

Song Y Q, Yan Z. Transformation and microstructure of as-rolled Si-Mn-Cr dual phases steels
［J］. Iron & Steel, 1995, 30(12): 51-54.

［6］狄国标, 陈连生，刘振宇,等. 低成本热轧双相钢组织性能研究
［J］. 轧钢, 2007, 24(5): 17-20.

Di G B, Chen L S, Liu Z Y, et al. Microstructure and mechanical properties research of low cost hot rolled dual phase steel
［J］. Steel Rolling, 2007, 24(5): 17-20.

［7］董瑞峰，李德刚，闫波,等. 碳当量对C-Mn型热轧双相钢组织性能的影响
［J］. 轧钢, 2011, 28(3): 11-13.

Dong R F, Li D G, Yan B, et al. Effects of carbon equivalent on microstructure and properties of C-Mn hot rolled dual-phase steel
［J］. Steel Rolling, 2011, 28(3): 11-13.

［8］董毅，时晓光，韩斌. 终轧温度对热轧细晶双相钢组织与性能的影响
［J］. 金属热处理, 2011, 36(1): 64-67.

Dong Y, Shi X G, Han B. Effect of finishing rolling temperature on microstructure and properties of fine grained hot-rolled dual-phase steel
［J］. Heat Treatment of Metals, 2011, 36(1): 64-67.

［9］徐浩浩, 许晓嫦, 张永. 热轧双相钢的疲劳失效机理研究
［J］. 矿冶工程, 2014, 34(4): 122-127.

Xu H H, Xu X C, Zhang Y. Investigation on fatigue failure mechanism of hot rolled dual phase steel
［J］. Mining and Metallurgical Engineering, 2014, 34(4)：122-127.

［10］Kim N J, Thomas G. Effects of morphology on the mechanical behavior of a dual phase Fe/2Si/0.1C steel
［J］. Metall. Trans. A,1981, 12(3): 483-489.

［11］Suh D, Kwon D, Lee S, et al. Orientation dependence of micro fracture behavior in a dual-phase high-strength low alloy steel
［J］. Metall. Trans. A, 1997, 28(2)：504-509.

［12］林广，雷廷权.双相钢的疲劳行为(上)
［J］. 材料科学与工艺, 1993, 1(2): 102-110.

Lin G Y, Lei T Q. Fatigue behavior of dual phase steels
［J］. Materials Science and Technology, 1993, 1(2): 102-110.

［13］Sherman A M, Davies R G . The effect of martensite content on the fatigue of a dual-phase steel
［J］. International Journal of Fatigue, 1981, 3(1):36-40.

Service：

【This site has not yet opened Download Service】【Add Favorite】