DP1180钢的热变形Arrhenius本构模型  

Arrhenius Constitutive Model for Hot Deformation of DP1180 Steel

作　　者：高兴健 刘鑫 罗健 王文礼[2] GAO Xingjian;LIU Xin;LUO Jian;WANG Wenli(Manufacturing Management Department,Baosteel Zhanjiang Iron and Steel Co.,Ltd.,Guangdong Zhanjiang 524076,China;School of Metallurgical Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,China)

机构地区：[1]宝钢湛江钢铁有限公司制造管理部,广东湛江524076 [2]西安建筑科技大学冶金工程学院,西安710055

出　　处：《精密成形工程》2024年第11期108-116,共9页Journal of Netshape Forming Engineering

基　　金：宝钢湛江钢铁有限公司企业科研项目(2023038)

摘　　要：目的研究DP1180钢热变形行为,为热加工数值模拟提供理论指导。方法利用热模拟试验机Gleeble-3800对DP1180钢在变形温度为950~1250℃和应变速率为0.001~1 s^(-1)条件下进行高温拉伸实验,根据实验数据绘制不同变形温度及应变速率下的真应力-真应变曲线。基于Arrhenius双曲正弦本构模型,考虑应变对特征参数的影响,选取应变范围为0.04~0.2的应力,通过四次多项式拟合建立DP1180钢的热变形本构模型,并通过对比模型计算值与实验值,采用相关性及误差分析验证本构模型的预测精度。结果DP1180钢的真应力-真应变曲线在应变速率为1s^(-1)时呈现明显动态再结晶特征,高温流变应力随变形温度的升高而降低,随应变速率的增大而增大。考虑应变影响的本构模型预测值与实验值的相关系数为0.9873,平均相对误差为5.18%,吻合度较高。结论DP1180钢的高温流变应力受材料加工硬化与动态软化相互竞争的影响,在高变形温度、低应变速率条件下软化机作用更加明显。考虑变形温度、应变速率及应变量建立的Arrhenius本构模型具有较高的预测精度,可以对DP1180钢热变形过程中的流变应力进行准确预测。The work aims to study the hot deformation behaviour of DP1180 steel and provide the theoretical guidance for the numerical simulation of hot forming.The high-temperature tensile test of DP1180 steel was carried out at deformation tem-perature ranging from 950 to 1250℃and strain rate ranging from 0.001 to 1 s^(-1)with a thermal simulation tester Gleeble-3800,and the true stress-true strain curves at different deformation temperature and different deformation rates were plotted according to the experimental data.The hot deformation constitutive model of DP1180 steel was established by considering the effects of strain on the characteristic parameters,based on the Arrhenius hyperbolic sinusoidal constitutive model.A strain range of 0.04-0.2 was selected,and a quadratic polynomial was fitted to the model.The calculated values of the model were compared with the experimental values,and correlation and error analyses were used to verify the prediction accuracy of the constitutive model.The true stress-true strain curve of DP1180 steel showed obvious dynamic recrystallisation characteristics at a strain rate of 1 s^(-1).The high temperature flow stress decreased with the increase of deformation temperature and increased with the in-crease of strain rate.The correlation coefficient of the predicted value of the constitutive model taking into account the effect of the strain with the experimental value was 0.9873,and the average relative error was 5.18%,which showed a high coin-cidence.The flow stress of DP1180 steel at high temperature is affected by the competing effects of material work-hardening and dynamic softening.The role of the softening machine becomes more pronounced at high deformation temperature and low strain rate.The Arrhenius constitutive model,which is established by considering the deformation temperature,strain rate and strain variables,has high prediction accuracy and can accurately predict the flow stresses during the hot deformation of DP1180 steel.

关 键 词：DP1180钢 高温拉伸 Arrhenius本构模型 流变应力 预测精度 

分 类 号：TG142.2[一般工业技术—材料科学与工程]