Elastic-plastic deformation of lightweight core-perforated sheet metal laminates and their optimum design considering strength, rigidity and formability

轻质带芯穿孔金属层合板的弹塑性变形及其考虑强度、刚度和成型性的优化设计

基本信息

批准号：
12555029
负责人：
YOSHIDA Fusahito
金额：
$ 6.53万
依托单位：
HIROSHIMA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2002
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12555029/
关键词：
perforated sheet sheet metal laminate lightweight rigidity strength elasto-plasticity optimum design press-formability

项目摘要

In this project, sandwiched metal plates with perforated core and skins are newly developed for the use of lightweight shell constructions. Using copper sandwiched specimens, mechanical properties of elasto-plasticity of this type of plates were examined by performing several mechanical tests such as uniaxial tension, bending and stretch forming. Moreover, the mechanisms of elastic-plastic deformation and the forming limit of this plate were investigated by the finite element analysis. The present findings are summarized as follows:(1) The plastic-flow strength of the sandwiched plate (its volume fraction of voids V_f = 17%), as well as a monolithic copper sheet and a single perforated sheet (V_f = 28 were examined by uniaxial tension tests. For the single perforated sheet the specific strength (= strength divided by the density of the plates) is 28% less than that of the monolithic sheet, while for the sandwich plate it is only 5% less. The sandwich plate has excellent performance in bending rigidity, namely it is as high as 2.7 times of one of the monolithic plate.(2) The forming limit diagram (FLD) of the sandwiched plate is similar to one of the single perforated sheet. The limit strain under plane-strain condition is not so small compared to one of the monolithic sheet, while it under balanced biaxial stretching condition is significantly smaller than that under uniaxial tension. From the experimental observations, as well as the FE simulation, it is concluded that the fracture of the sandwich plate will occur as a result of strain localization at the skin metals.

在该项目中，新开发了带有穿孔芯材和蒙皮的夹层金属板，用于轻质外壳结构。使用铜夹层试样，通过单轴拉伸、弯曲和拉伸成型等多项力学试验来检验此类板材的弹塑性力学性能。此外，通过有限元分析研究了该板的弹塑性变形机理和成形极限。目前的研究结果概括如下：(1)对夹层板(其空隙体积分数V_f=17%)、整体铜板和单孔板(V_f=28)的塑性流动强度进行了检验。通过单轴拉伸测试，单孔板的比强度（=强度除以板的密度）比整体板低 28%，而夹层板仅为 5%。夹芯板的弯曲刚度性能优异，高达单片板的2.7倍。(2)夹芯板的成形极限图(FLD)与单层冲孔板相似。从实验观察以及有限元模拟来看，平面应变条件下的极限应变与整体板相比并不小，而平衡双轴拉伸条件下的极限应变明显小于单轴拉伸条件下的极限应变。结论是夹层板的断裂将由于表皮金属处的应变局部化而发生。