800MPa级高强塑积冷轧带钢组织和性能研究

Study on Microstructure and Properties of 800 MPa Grade Cold Rolled Strip with High Product of Strength and Elongation

针对相变诱发塑性钢CR420/780TR的退火工艺、组织和力学性能展开研究,并通过工业试制,与传统双相钢的组织、性能进行对比。结果表明:强度随着退火过程均热温度升高而降低,随缓冷温度升高而提高,随快冷终止温度的升高而降低。河钢集团邯钢公司开发的相变诱发塑性钢CR420/780TR,性能满足国标要求,组织由铁素体、贝氏体及残余奥氏体构成,残余奥氏体含量达13%。与同级别双相钢CR420/780DP相比,CR420/780TR钢的断后延伸率更高,成型性能更好。

The annealing process,microsctructure and mechanical properties of TRIP steel CR420/780 TR are studied and the steel is trial-produced commercially,of which the microstructure and mechanical properties are compared with those of traditional dual-phase steel.The results show that the strength dccreases with the increase of soaking temperature during annealing,increases with the rise of slow cooling temperature and decreases with the rise of fast cooling finish temperature.The mechanical properties of the TRIP steel CR420/780 TR developed by Hansteel of HBIS Group satisfy the national standard requirements,the microstructure consists of ferrite,bainite and residual austenite,the content of the residual austenite is up to 13%.Compared with the dual-phase steel CR420/780 DP of same grade,the elongation ratio after fracture of CR420/780 TR steel is higher with better forming performance.