【摘要】 为模拟高强钢转向节淬火后的微观组织和硬度分布，使用Jmatpro软件计算了42CrMo钢的热物性参数和等温转变曲线，获得了42CrMo钢的珠光体、贝氏体、马氏体转变动力学模型参数。基于Comsol软件建立了42CrMo钢淬火过程的传热、相变多场耦合有限元分析模型，模拟了转向节在PAG(聚烷撑乙二醇水溶液)中淬火冷却的过程，获得了温度、微观组织和硬度分布。分析了锻件杆部淬火后的硬度和显微组织，并与模拟结果进行对比。模拟结果表明：锻件杆部表面主要为82.1%的马氏体和17.9%的贝氏体，硬度为31.9 HRC,心部主要为15.9%的马氏体、72.5%的贝氏体、9.1%的铁素体和2.5%的珠光体，硬度为26.8 HRC。试验测得的锻件表面硬度最高为32.0 HRC,心部硬度最低为26.4 HRC,表面的组织为短板条状马氏体和部分粒状下贝氏体，心部为针状马氏体、羽毛状上贝氏体和铁素体，模拟结果与试验结果基本吻合，表明建立的多场耦合有限元分析模型能准确预测高强钢转向节锻件淬火微观组织和硬度分布。更多还原

【Abstract】 In order to simulate the microstructure and hardness distribution of high strength steel steering knuckle after quenching, the thermophysical parameters and isothermal transformation curves of 42CrMo steel were calculated using Jmatpro software, and the kinetic model parameters of pearlite, bainite and martensite transformation of the 42CrMo steel were obtained. A multi field coupled finite element analysis model for heat transfer and phase transformation during the quenching process of the 42CrMo steel was established based on Comsol software. The quenching and cooling process of the steering knuckle in PAG(polyalkylene glycol aqueous solution) was simulated, and the temperature, microstructure and hardness distribution were obtained. The hardness and microstructure of the forged rod after quenching were analyzed and compared with the simulation results. The simulation results show that the surface of the forged rod is mainly composed of 82.1% martensite and 17.9% bainite, with a hardness of 31.9 HRC. The center is mainly composed of 15.9% martensite, 72.5% bainite, 9.1% ferrite and 2.5% pearlite, with a hardness of 26.8 HRC. The maximum surface hardness of the forgings measured by the experiments is 32.0 HRC, and the minimum hardness of the center is 26.4 HRC. The surface microstructure is short lath martensite and some granular lower bainite, and the center is needle martensite, feathery upper bainite and ferrite. The simulation results are basically consistent with the test results, indicating that the established multi field coupled finite element analysis model can accurately predict the quenching microstructure and hardness distribution of high strength steel steering knuckle forgings.更多还原