Abstract: Test low carbon bainitic steel (0.042～0.045C,1.43～1.47Mn,1.0～2.5Cu,0.29 ～0.30Mo, 0.025~0.029Nb,0.011~0.018Ti,0.0013~0.0023B) was melted by a 50kg vacuum induction furnace. Teat results showed that with increasing Cu content from 1.0% to2.5%,the precipitation speed of e-Cu in steel and the peak hardness increased; and with increasing Cu%, the yield strength of direct-quenching(DQ)steel after rolling increased from 865 MPa to918 MPa and the yield strength of DQ + 500 ℃ tempering steel increased from 935 MPa to1140 MPa, while the tensile strength and impact toughness of DQ+500 ℃ tempering1.0~2.5Cu steel were lower than that of DQ steel.

摘要： 实验用低碳贝氏体钢(%:0.042～0.045C、1.43～1.47Mn、1.0～2.5Cu、0.29～0.30Mo、0.025~0.029Nb、0.011~0.018Ti,0.0013~0.0023B)由50 kg真空感应炉冶炼。实验结果表明，随铜含量由1.0%增加至 2.5%,8-Cu在钢中沉淀速度加快，峰值硬度增大；随Cu%的增加，轧后直接淬火(DQ)钢的屈服强度由865 MPa增 至918 MPa, DQ+500℃回火钢的屈服强度由935 MPa增至1140 MPa,但1.0%~2.5%Cu DQ+500 ℃回火钢的抗 拉强度和冲击韧性均比DQ态钢有所降低。

关键词: 超高强度, 低碳贝氏体,  ε-Cu沉淀 , 力学性能