摘要
结合5083H111铝合金较宽应变率范围2×10^-4～4×10^2s^-1内的拉伸实验数据，揭示该铝合金的拉伸“V”型率效应特征，分析对数应变率敏感系数A和切线模量Et的应变率和应变相关性，进而通过对Johnson Cook模型的修正来建立合理描述5083H111铝合金较宽应变率范围内力学行为的动态拉伸本构模型．建立的动态本构模型中，流动应力包括应变率相关和应变相关两部分．该模型合理描述了5083H111铝合金的拉伸“V”型率效应特征，预测结果与实验结果较为一致．另外，结合破坏应变的对数应变率敏感系数口，得到了拉伸破坏应变预测方程，其预测结果也与实验结果基本一致．
Combined with tensile experimental data of 5083H111 aluminum alloy at a wide range of strain rates from 2×10^-4 to 4×10^2s^-1 ,the V-typed strain rate effect of this aluminum alloy is analyzed. The strain-rate and strain dependence of the logarithmic strain rate sensitivity coefficient ）, and tangent modulus Et are discussed. Then,a dynamic constitutive model is established to describe the dynamic tensile behavior of 5083H111 aluminum alloy at a range of lower and middle strain-rates by modifying the Johnson-Cook model. The model captures successfully the V-typed strain-rate effect of tensile deformation of the aluminum alloy at the considered strain-rates, showing good agreement with the experimental ones. Furthermore, based on the logarithmic strain-rate sensitivity coefficient β of failure strain,a new equation to predict the tensile failure strain of the alloy is formulated, which is basically consistent with the experimental ones.
出处
《固体力学学报》
CAS
CSCD
北大核心
2014年第3期259-265,共7页
Chinese Journal of Solid Mechanics
基金
牵引动力国家重点实验室自主重点课题(2011TPL-Z03)资助
关键词
5083H111铝合金
动态拉伸
宽应变率
动态本构模型
破坏应变
5083Hlll aluminum alloy,dynamic tension,a wide range of strain rate,dynamic constitutive model ,tensile failure strain
