基于ABAUQS-Matlab对42CrMo钢表面感应淬火奥氏体化参数的研究

目的 确定42CrMo钢感应淬火过程的奥氏体相变动力学参数，并验证其可靠性。方法 根据不同加热速率下42CrMo钢奥氏体膨胀曲线，基于经典JMAK（Johnson-Mehl-Avrami-Kolmogorov）模型和Kissinger方法，确定了42CrMo钢奥氏体化相变动力学的参数。建立ABAQUS局部移动式感应淬火模型，选取淬火区域加热过程中点的温度变化曲线作为验证奥氏体化模型的对象。基于Scheil法则和JMAK相变动力学模型，采用文中求解得到的奥氏体化参数，采用Matlab对42CrMo连续转变过程离散为每个时间间隔的等温相变并求解，并对照相关学者采用的扩展解析动力学模型和JAMK模型，加以验证。结果 根据上述方法，得到的42CrMo奥氏体相变动力学参数为：激活能Q为2.04×106 J/mol，指前因子lnk0的值取230.78，Avrami指数n取0.427。将淬火加热过程离散为数量很大的均匀时间间隔，并以求解的动力学模型在每个间隔内进行对应温度条件下奥氏体体积分数的求解并顺次叠加，以模拟得到的奥氏体转变时间和转变温度等作为依据，该模型有良好的表现性。结论 对42CrMo非等温且加热速度不恒定的连续奥氏体转变过程，JAMK模型拟合表现良好，采用文中求解的参数组对表面感应淬火的奥氏体转变历程进行仿真预测是可行的。

42CrMo Austenitization Kinetic Parameters in Induction Hardening Process Based on ABAQUS-Matlab

The work aims to determine the austenitization kinetics parameters of 42CrMo steel and verify the reliability of the parameters. The austenitization kinetics parameters of 42CrMo steel were determined according to the austenitic expansion curves of 42CrMo steel with different heating rates via the classical JMAK (Johnson-Mehl-Avrami-Kolmogorov) model and Kissinger method. The ABAQUS local moving induction hardening model was established, and the temperature change curve of the heating point in the hardening area was selected as the object to verify the austenitization model. Based on Scheil law and JMAK transformation kinetics model, the austenitization parameters obtained were used to discretize the continuous transformation process of 42CrMo into isothermal transformation at each time interval in Matlab and provide solution and carry out verification according to the extended analytical kinetics model and JAMK model adopted by relevant scholars. The austenitization kinetics parameters of 42CrMo obtained according to above methods were: activation energy of 2.04×106 J/mol, pro-exponential factor lnk0 of 230.78, and Avrami exponent n of 0.427, respectively. The hardening heating process could be divided into a large number of uniform time intervals, and the solved kinetics model was used to solve the austenite volume fraction at the corresponding temperature in each interval, which was superimposed in sequence. Based on the simulated austenite transformation time and transformation temperature, the model had good performance. JAMK model fits well for the continuous austenite transformation process of 42CrMo with non-isothermal and non-constant heating rate. It is feasible to use the parameter set solved in this work to simulate and predict the austenite transformation process of surface induction hardening.