摘要
目的掌握不同条件下15CrMoG的高温流变规律,为热加工工艺提供参考。方法在变形温度为900~1200℃、应变速率为5~20 s^(−1)条件下,采用Gleeble热模拟试验机对15GrMoG耐热钢进行等温压缩试验。基于试验数据,采用线性拟合及自定义非线性拟合方法,求解Hansel-Spittel(H-S)本构模型的材料参数。由于H-S本构模型中的参数A对应变的敏感性较高,因此采用应变的多项式拟合方法,替代常规的数值平均法,以修正参数A,从而提升H-S模型的精度。结果随变形温度的降低或应变速率的升高,15CrMoG合金钢的真实应力-应变曲线整体向高应力区偏移,表明该合金钢的流动应力符合典型合金钢的热变形行为。所构建的本构模型的预测应力值与等温压缩试验应力值的相关系数R和平均绝对相对误差分别为0.99745和2.3243%。经修正后,相关系数R达到0.99813,同时平均绝对相对误差降低至1.8123%。结论对Hansel-Spittel进行修正可更准确地描述15CrMoG的高温变形行为,修正参数A后的H-S本构模型具有较高的准确性和预测效能。
The work aims to grasp the high-temperature rheological law of the material under different conditions and pro-vide a reference for the hot working process.An isothermal compression test of 15GrMoG heat-resistant steel was conducted at deformation temperature of 900-1200℃and a strain rate of 5-20 s^(−1)with a Gleeble thermal simulation testing machine.Based on the experimental data,the material parameters of the Hansel-Spittel(H-S)constitutive model were solved by linear fitting and custom nonlinear fitting methods.Due to the high sensitivity of parameter A in the H-S constitutive model,the polynomial fitting method of strain was used instead of the conventional numerical average method to correct parameter A,so as to improve the accuracy of the H-S model.The result showed that the real stress-strain curve of 15CrMoG alloy steel shifted to the high stress zone with the decrease of deformation temperature or increase of strain rate,indicating that the flow stress of the alloy steel conformed to the thermal deformation behavior of typical alloy steel.The correlation coefficient R and the average absolute relative error of the predicted stress value and the experimental stress value of isothermal compression of the constructed con-stitutive model were 0.99745 and 2.3243%,respectively.After correction,the correlation coefficient R reached 0.99813,and the average absolute relative error was reduced to 1.8123%.The conclusion indicates that the high-temperature deformation behavior of 15CrMoG can be more accurately described by the Hansel-Spittel correction,and the H-S constitutive model after correction of parameter A has good accuracy and prediction performance.
作者
付文涛
王伟
马世博
穆振凯
王宝雨
刘宏伟
FU Wentao;WANG Wei;MA Shibo;MU Zhenkai;WANG Baoyu;LIU Hongwei(School of Materials Science and Engineering,Hebei University of Science and Technology,Shijiazhuang 050018,China;Hebei Key Laboratory of Material Near-net Forming Technology,Hebei University of Science and Technology,Shijiazhuang 050018,China;School of Mechanical Engineering,University of Science and Technology Beijing,Beijing 100083,China)
出处
《精密成形工程》
北大核心
2025年第6期206-214,共9页
Journal of Netshape Forming Engineering
基金
国家自然科学基金(52205353)
河北省创新能力提升计划(225A2201D)。
