【摘要】 通过真空感应炉熔炼和浇铸的50 kg锭锻成40 mm×150 mm坯和热轧成10 mm板以及热模拟试验研究了开发的低硅Nb-Ti微合金化双相钢(/%:0.082C,0.15Si,1.20Mn,0.010P,0.002S,0.020Nb,0.015Ti,0.045Al,0.003 5 N)静态和动态连续冷却转变(CCT)曲线、组织(11%马氏体+89%铁素体)和力学性能(抗拉强度682 MPa)。并通过铁水脱硫-260 t BOF-LF-RH-230 mm×1 300 mm连铸-热轧工艺试制了低硅双相钢(/%:0.075C,0.15Si,1.16Mn,0.012P,0.003S,0.016Nb,0.015Ti,0.033Al,0.004 3 N)3.5mm板。结果表明,精轧出口温度810℃,水冷至700℃,空冷4.5 s,卷取温度150℃时,该钢的组织为15%马氏体+85%铁素体,晶粒度12~12.5级,抗拉强度672~692 MPa,伸长率24.0%~28.5%,屈强比0.65~0.67,钢板冲压成塑性能优良,制造的轿车轮辐弯曲疲劳性能15×10~4次。更多还原

【Abstract】 The static and dynamic continuous cooling transformation(CCT) curves,structure(11%martensite +89%ferrite) and mechanical properties(tensile strength 682 MPa) of developed low silicon and Nb-Ti Microalloying dual phase steel(/%:0.082 C,0.15 Si,1.20 Mn,0.010 P,0.002 S,0.020 Nb,0.015 Ti,0.045A1,0.0035N) have been tested and studied by melting in a vacuum induction furnace,casting 50 kg ingot,forging to 40 mm x 150 mm slal) and hot rolling to 10 mm plate and thermal simulation testing.And 3.5 mm low silicon dual phase steel plate(/%:0.075 C,0.15 Si,1.16 Mn,0.012 P,0.003 S,0.016 Nb,0.015 Ti,0.033A1,0.0043N) has been pilot-produced by hot metal desulphurization-260 t BOF-LF-RH-230 mm × 1 300 mm slab concasting-hot rolling process.Results show that with finished rolling 810 ℃,water cooling to 700 ℃,air cooling for 4.5 s and coiling at 150 ℃,the structure of steel is 15%+85%ferrite with gain size rating 12-12.5,the tensile strength of steel is 672-692 MPa with yield-ultimate strength ratio0.65- 0.67,and the yield of steel is 24.0%- 28.5%.The steel plate has nice stamping performance and the bending fatigue life of manufactured wheel rib of car is 15×10~4.更多还原