连续淬火回火工艺对30MnSi钢棒组织性能的影响

Effects of continuous quenching and tempering on microstructure and properties of 30MnSi steel bar

研究由PLC系统控制的淬回火工艺及张力对30MnSi钢棒组织性能的影响。结果表明,随着淬火温度的升高,钢棒抗拉强度先升高后降低,断后伸长率逐渐降低;回火温度较高时,淬火温度对钢棒断后伸长率的影响相对于低温回火时小。钢棒松弛率随张力的增加先减小后增加,张力大小为4%抗拉强度时,松弛率最小。钢棒经940℃淬火+480℃回火后,组织为回火屈氏体,综合性能良好。

By use of PLC control production process , effects of continuous quenching , tempering and tension on microstructure and properties of 30MnSi hot rolled steel bar were studied .The results show that with quenching temperature increasing , the tensile strength of the steel bar first increases and then decreases , elongation decreases gradually .When the tempering at high temperature , influence of quenching temperature on the elongation is relative lower than that of the low temperature tempering .The relaxation rate of the steel bar decreases first and then increases with the tension increasing .The relaxation rate is the minimum when tension is 4% tensile strength .After quenched at 940 ℃and tempered at 480 ℃, the steel bar has the microstructure of tempered troostite and good comprehensive properties .