基于修正流变应力的6013铝合金本构方程和热加工图  

Constitutive equation and processing maps of 6013 aluminum alloy based on corrected flow stress

作　　者：伍英明 姜科达 刘胜胆[1,2,3] 叶凌英[1,3] 陈高剑 WU Yingming;JIANG Keda;LIU Shengdan;YE Lingying;CHEN Gaojian(School of Materials Science and Engineering,Central South University,Changsha 410083,China;National Key Laboratory of Science and Technology on High-Strength Structural Materials,Central South University,Changsha 410083,China;Key Laboratory of Non-Ferrous Metal Materials Science and Engineering,Ministry of Education,Central South University,Changsha 410083,China)

机构地区：[1]中南大学材料科学与工程学院,湖南长沙410083 [2]中南大学轻质高强结构材料重点实验室,湖南长沙410083 [3]中南大学有色金属材料科学工程教育部重点实验室,湖南长沙410083

出　　处：《中南大学学报（自然科学版）》2024年第9期3282-3293,共12页Journal of Central South University:Science and Technology

基　　金：国家重点研发计划项目(2023YFB3710404)。

摘　　要：基于6013铝合金热压缩原始真应力-应变曲线,在摩擦、温度双修正基础上建立应变修正后的Arrhenius本构方程,并对模型进行误差分析。根据动态材料模型理论和Prasad失稳判据,建立6013铝合金变形温度为530~575℃、应变速率为0.001~0.1 s^(-1)条件下的热加工图。研究结果表明:经过摩擦和温度双修正后的应变修正Arrhenius本构方程预测精度更高,流变应力预测值和实验值之间的相关系数为0.997,平均绝对误差为0.3 MPa,平均相对误差仅为3.06%。在整个变形过程中没有失稳现象,功率耗散效率η在0.3以上,主要的软化机制为动态再结晶。随着功率耗散效率η从0.32增加到0.36,晶粒的形貌由扁平状转变为等轴状,晶粒平均等效圆尺寸逐渐减小。考虑细化合金的晶粒,变形温度为560~575℃、应变速率为0.03~0.1 s^(-1)是较合适的工艺参数。Based on the original true stress−strain curves of hot compression of 6013 aluminum alloy,the Arrhenius constitutive equation after strain correction was established on the basis of friction and temperature correction, and the error analysis of the model was carried out. According to the theory of dynamic material model and Prasad instability criterion, the processing map of 6013 aluminum alloy was established under the condition of deformation temperature of 530−575 ℃ and strain rate of 0.001−0.1 s^(−1). The results show that the strain modified Arrhenius constitutive equation after both friction and temperature correction has higher prediction accuracy. The correlation coefficient between the predicted and experimental values of flow stress is 0.997, the average absolute error is 0.3 MPa, and the average relative error is only 3.06%. There is no instability phenomenon in the whole deformation process, and the power dissipation efficiency η is above 0.3. The dynamic recrystallization is the main softening mechanism. As the power dissipation efficiency η increases from 0.32 to 0.36, the morphology of the grains changes from flat to equiaxed, and the average equivalent circle size of the grains gradually decreases. The temperature of 560−575 ℃ and strain rate of 0.03−0.1 s^(−1) are optimal parameters to refine grains after deformation.

关 键 词：金属材料 6013铝合金 Arrhenius本构方程 热加工图 

分 类 号：TG146.2[一般工业技术—材料科学与工程]