热连轧双相钢的控制轧制与控制冷却

CONTROLLED ROLLING AND CONTROLLED COOLING FOR DUAL PHASE STEELS IN HOT STRIP MILL

在多边形铁素体的基体上分布一定量马氏体组织的双相钢,具有较高的强度,良好的塑性和优异的成型性,制作汽车零部件可减重20%左右。与热处理型双相钢比,热轧双相钢的成本较低,因其不需专门的热处理设备,可直接在连轧机上用控轧工艺生产出性能适宜的双相钢板。本文叙述用热连轧机生产 Si-Mn-Cr-Mo 双相钢的方法及其适宜的生产工艺。研究表明,在热连轧机上用控轧控冷工艺完全可生产出σ_b≥590MPa、σ_(0.2)≤390MPa、σ_5≥25%、宽冷弯(B=35mm,d=a)合格的双相钢板,以满足汽车工业发展的需要,

Dual-phase steels with a proper amont of martensite structure in polylateral ferrite havefeatures of high strength,good plasticity and formability.It can be used to manufacture auto-mobile parts with 20% reduction of weight.Compared with heat treated dual-phase steels,the controllod hot-rolled ones have the advan-tage of lower cost,because there is no heat-treating equipment needed.This article describes the process to produce Si-Mn-Cr-Mo dual-phase steels on a continuoushot-strip mill.The results show that the products of dual-phase steels from the continuous hot-strip mill give the σ_bb≥590MPa,σ_(?)≤390MPa,σ_5≥25% and good wide cold bending test(B=35mm,d=α)and can meet the great demand of developing automobile industry.