硼对780MPa低碳贝氏体钢组织和力学性能的影响

摘要

试验低碳贝氏体钢(/％:0.08C,0.11～0.13Si,1.10～1.20Mn,0.008 ～0.009P,0.002S,0.21～0.23Ni,0.020 ～0.021Ti,0.003～0.004Nb,0 ～0.0010B,0.0007 ～0.0008O,0.003 1 ～0.003 3N)由50 kg真空感应炉熔炼,轧成45 mm钢板,并经930 ℃淬火,610℃回火.研究了0.001 0％硼对780 MPa低碳贝氏体钢45 mm板组织和力学性能的影响.结果表明,硼可显著提高试验钢的淬透性,不含硼试验钢淬火后得到粒状贝氏体,0.001 0％硼试验钢淬火后得到板条贝氏体.硼明显改善试验低碳贝氏体钢的力学性能,含0.001 0％硼试验钢淬、回火后的抗拉强度834 MPa和屈服强度771 MPa远高于不含硼试验钢的抗拉强度702 MPa和屈服强度591 MPa,实际生产中应加入适量硼可使低碳贝氏体钢得到板条贝氏体.