A multiscale experimental approach to characterize micro-to-macro transition length scale in polymer foams
A multiscale experimental approach to characterize micro-to-macro transition length scale in polymer foams
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DOI：
10.1016/j.mechmat.2021.104006
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发表时间：
2021-08-04
影响因子：
3.9
通讯作者：
Youssef, George
中科院分区：
文献类型：
--
作者：
Koohbor, Behrad;Pagliocca, Nicholas;Youssef, George
在非均质材料的多尺度研究中，微观力学响应与宏观行为之间的桥梁是核心。因此，定量表征的过渡长度尺度，相关的微观和宏观尺度的行为是非常重要的。泡沫和其他蜂窝结构中所谓的过渡长度尺度的实验表征是极其稀缺的。本工作报告的实验统计方法提出量化的微观到宏观的过渡长度尺度的聚合物泡沫。在这项工作中提出的方法使用全场应变分布测量的数字图像相关（DIC）在两个尺度作为输入。的过渡长度尺度的物理尺寸确定通过实施一个统计算法的基础上获得的DIC的局部应变数据的空间平均。有趣的是，微观和宏观尺度变形之间的过渡被发现是一个函数的材料密度，但独立的全球应变和应力施加。本研究结果提供了直接验证的代表性体积元（RVE）的大小在细胞固体的计算方法确定。
Bridging between micromechanics response and macroscopic behavior is at the core of multiscale investigations in heterogeneous materials. As such, quantitative characterization of the transitional length scales that correlate micro and macroscale behaviors is of great importance. Experimental characterization of the so-called transitional length scales in foams and other cellular structures is extremely scarce. The present work reports on an experimental-statistical approach proposed to quantify the micro-to-macro transition length scale in polymeric foams. The approach proposed in this work uses full-field strain distributions measured by digital image correlation (DIC) at two scales as input. The physical dimensions of the transition length scale are identified by implementing a statistical algorithm based on spatial averaging of the local strain data obtained from DIC. Interestingly, the transition between micro and macroscale deformation is found to be a function of material density but independent of global strain and stresses applied. The present results provide direct validations to representative volume element (RVE) size in cellular solids determined by computational methods.