Microstructures and Properties of Ferrite/Bainite DualPhase Steels With High HoleExpanding Ratio
CAI Minghui1,DING Hua1,2,ZHANG Jiansu3,TANG Zhengyou1,WANG Weiwei1
1. School of Materials and Metallurgy, Northeastern University, Shenyang 110004, Liaoning, China; 2. The State Key Lab. of Rolling and Automation of Northeastern University, Shenyang 110004, Liaoning, China;3. Bao Steel Technology Center, Baoshan Iron and Steel Group Co., Shanghai 201900, China
Abstract：The effects of Si and Mn contents on microstructure, mechanical properties and formability of low carbon SiMn steels were studied, and the crack propagation of ferrite/bainite dualphase steel was also investigated. The results showed that the increase in Si content increases the volume fraction of equiaxed ferrite. However, the increase in Mn content increases both strength and ductility, but decreases elongation and holeexpanding ratio. The crack of ferrite/bainite dualphase steel is formed by the mode of microvoid coalescence. When a microcrack meets the bainite,it mostly propagates along the phase interface between ferrite and bainite and by cutting off ferrite grains. The hotrolled ferrite/bainite dualphase steel, which has a holeexpanding ratio of 95% and good property combination, could be produced by designing proper contents of Si and Mn as well as parameters of TMCP.
蔡明晖;丁桦;张建苏;唐正友;王卫卫. 经济型铁素体/贝氏体高扩孔钢的组织与性能[J]. 钢铁, 2008, 43(8): 77-0.
CAI Minghui;DING Hua;ZHANG Jiansu;TANG Zhengyou;WANG Weiwei. Microstructures and Properties of Ferrite/Bainite DualPhase Steels With High HoleExpanding Ratio. Iron and Steel, 2008, 43(8): 77-0.
2008, Vol. 43 
