120t BOF-LF-CC板坯-8 mm板流程Nb-Ti微合金化大梁钢750L的开发与实践

采用120 t BOF-LF-连铸-控轧控冷工艺流程,开发出8 mm高强度汽车大梁钢750L(R_(m)≥750 MPa)。结果表明,通过750L钢Nb-Ti复合微合金化(/%:0.074C,0.11Si,1.51Mn,0.020P,0.002S,0.042Als,0.033Nb,0.109Ti),结合控轧控冷技术(精轧区压下量≥40%),生产的750L钢带的抗拉强度782~810 MPa,伸长率≥17.5%,晶粒度11.5~12.5级,冲击功≥90 J,各项技术指标满足并优于标准的要求。