1.School of Material and Metallurgy, Northeastern University, Shenyang 110004, Liaoning, China; 2.Cold Rolled Sheet Plant, Tangshan Iron and Steel Co., Ltd., Tangshan 063016, Hebei,China; 3.Minmetals Yingkou Medium Plate Co., Ltd., Yingkou 115005, Liaoning, China
Abstract：The effects of different cooling mode on microstructure and strengthflangeformability of low carbon FB steel used for automobile wheel were analyzed through TMCP(ThermoMechanical Controlled Process) tests. The fracture type and fracture mechanism of FB steel in hole expanding were also analyzed. The results show acicular ferrite(AF) and bainite were gained by continuous cooling. AF decreases the difference of microhardness between ferrite and bainite clearly， which improves the strengthflangeformability of steel. The fracture mechanism of FB steel is gliding fracture through micropore gathering. The results can offer experiment data in order to the applying of lowcarbon FB steel on automobile wheel.
