通过对2Cr11MoVNbN钢的淬火温度、淬火液质量分数、冷却时间、回火温度4个热处理工艺参数的研究, 并以综合力学性能作为评价指标, 设计了正交试验, 以寻求该钢的最佳热处理工艺。结果表明: 最佳热处理工艺为淬火温度1 060 ℃、AQ251介质水溶液的质量分数12%、冷却时间3.5 min、回火温度640 ℃; 经最佳工艺热处理后其抗拉强度为974 MPa, 屈服强度为882 MPa, 伸长率为16.4%, 断面收缩率为52.6%, 冲击功为18 J, 硬度为315 HB, 组织均匀, 晶粒度为7.5级。

Attention was paid to four factors of heat treatment, such as, quenching temperature, medium water concentration, cooling time and tempering temperature. In order to find out the optimum heat treatment, comprehensive mechanical properties were used as evaluating index, and orthogonal test was designed. The results show that quenching temperature of 1 060 ℃, AQ251 medium water concentration of 12%, cooling time of 3.5 min and tempering temperature of 640 ℃ were the best match. After the optimum treatment, the tensile strength was 974 MPa, the yield strength was 882 MPa, the elongation was 16.4%, the reduction of area was 52.6%, the impact energy was 18 J, the hardness was 315 HB, the microstructure was homogeneous and grain size reached 7.5 grade.