淬火温度对20CrMnTiH钢渗碳淬火后组织与残留应力的影响

Influence of quenching temperature on phase and residual stress of 20CrMnTiH steel after carburizing and quenching process

根据过冷奥氏体等温转变曲线,建立了20CrMnTiH钢的组织转变模型;利用有限元软件中的热处理模块,对20CrMnTiH钢的渗碳淬火过程进行了有限元数值模拟;分析了不同淬火温度对渗碳淬火后的组织和残留应力的影响;并对渗碳淬火后的组织进行了金相试验分析。结果表明:模拟结果与试验结果相吻合,证明了20CrMnTiH钢相变模型的正确性;同时提出淬火温度在Ac_3温度以上时对组织转变的影响不大,降低淬火温度可以显著降低零件淬火后的残留应力。

According to the isothermal transformation curve of undercooling austenite, the structure transformation model of 20CrMnTiH steel was established. The heat treatment module of finite element software was used to numerical simulate the carburizing and quenching process of 20CrMnTiH steel. The effect of different quenching temperature on the mierostructure and residual stress after c^trburizing and quenching was analyzed. Final- ly, the metallographic test of microstracture was analyzed. The result showed that the simu- lation results were coincided with the experimental results, which showed the correctness of the phase change model of 20CrMnTiH steel. The quenching temperature has little effect on the transformation of the structure when the temperature was above Ac~ and residual stress after quenching was significantly reduced by reducing the quenching temperature.