基于有限元对薄膜真实应力应变数据的修正  

Correction of Real Stress-strain of Film Based on Finite Element Method

作　　者：徐雅 付志强[1] 周传浩 刘艳华[1] 何争辉 张蕾[1] 任慧慧 XU Ya;FU Zhi-qiang;ZHOU Chuan-hao;LIU Yan-hua;HE Zheng-hui;ZHANG Lei;REN Hui-hui(Packaging Innovation Design Laboratory,School of Light Industry Science and Engineering,Tianjin University of Science and Technology,Tianjin 300457,China;Tianjin Rich Creation Technology Co.,Ltd.,Tianjin 300220,China)

机构地区：[1]天津科技大学轻工科学与工程学院包装创新设计实验室,天津300457 [2]天津茂创科技发展有限公司,天津300220

出　　处：《塑料工业》2021年第7期144-147,116,共5页China Plastics Industry

基　　金：天津市教委科研计划(自然科学)(2019KJ209)。

摘　　要：由于薄膜拉伸过程中存在颈缩现象,工程应力应变数据不能真实反映薄膜塑性阶段的本构关系。基于工程、对数及有限元应力修正法得到的修正应力应变数据进行薄膜的单轴拉伸仿真,基于实验数据对比三种仿真结果。工程应力应变仿真结果与实验曲线最大误差为90.2%;对数应力应变仿真结果在位移5 mm内与实验最大误差为2%,位移5 mm后误差逐渐增大至61.6%;有限元修正后的应力应变仿真结果与实验数据基本吻合,最大误差为8%。修正应力与对数应力在应变0.5以内相同,应变0.5后,修正应力与对数应力的比值呈线性递增。基于有限元应力修正法的修正数据更能表达薄膜材料的真实应力应变关系,为薄膜的工程应用奠定了基础。Due to the necking phenomenon in the tensile process of the film,the engineering stress-strain could not truly reflect the constitutive relation of the plastic stage of the film.The uniaxial tensile simulation of the film was carried out based on the modified stress-strain data obtained by engineering,logarithmic and finite element stress correction method,and the three simulation results were compared based on the experimental data.The maximum error between the engineering simulation results and experimental curve is 90.2%,the maximum error between the logarithmic simulation results and experiment is 2%with in 5 mm of displacement,and the error gradually increases to 61.6%after 5 mm.The revised stress-strain simulation results are basically consistent with the experimental data,and the maximum error is 8%.The corrected stress is the same as the logarithmic stress within the strain 0.5.After the strain 0.5,the ratio of the modified stress to the logarithmic stress increases linearly.The modified data based on the finite element stress correction method could better express the real stress-strain relationship of film materials,which lays a theoretical foundation for the engineering application of films.

关 键 词：薄膜 颈缩 真实应力应变 单轴拉伸仿真 有限元应力修正法 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术]