Assari Amir Hossein, Shaghaghi Negar, Yaghoobi Saeid, Ghaderi Sahar
Department of Materials Science and Engineering, Sahand University of Technology, Tabriz, Iran.
School of Chemical Engineering, College of Engineering, University of Tehran, 16th Azar St., Enghelab Sq., Tehran, Iran.
Heliyon. 2024 Aug 16;10(16):e36489. doi: 10.1016/j.heliyon.2024.e36489. eCollection 2024 Aug 30.
The accurate evaluation of the effective mechanical properties of composites mainly depends on the characteristics of representative volume elements (RVEs). This paper mainly investigates the RVE size. Additionally, the effect of volume fraction of reinforcement, the edge effect, and RVE types on the critical size are discussed. First, the Al/Ni multilayered composites were processed by nine cycles of the cross-accumulative roll bonding (CARB) method. Then, one type of RVEs was created based on cross-sectional micrographs of composites to consider their inhomogeneities. Another type was generated by using the random sequential adsorption (RSA) procedure. Thereafter, the homogenized effective elastic properties of both types of microstructure-based RVEs and RSA-based RVEs were computed and compared as a function of the volume fraction of Ni and RVE size. The results showed that by increasing the Ni fragments, the RVEs indicated stiffer elastic behavior. By increasing the volume fraction of Ni from 0.2 Vf to 0.8 Vf, the Poisson ratio decreased by 7 % and the elastic modulus increased by 83 % for RSA-based RVE. Regarding the size of microstructure-based RVE of Al/Ni (0.8 Vf), from the largest size (size 1) with a length of 575 μm and a width of 575 μm to the smallest size (size 5) with a length of 287.5 μm and a width of 287.5 μm, the elastic modulus and the Poisson ratio showed 16 % and 0.8 % decrease, respectively.
复合材料有效力学性能的准确评估主要取决于代表性体积单元（RVE）的特性。本文主要研究RVE尺寸。此外，还讨论了增强体体积分数、边缘效应和RVE类型对临界尺寸的影响。首先，通过九个循环的交叉累积轧制结合（CARB）方法制备了Al/Ni多层复合材料。然后，基于复合材料的横截面显微照片创建了一种类型的RVE，以考虑其不均匀性。另一种类型是通过随机顺序吸附（RSA）程序生成的。此后，计算并比较了基于两种微观结构的RVE和基于RSA的RVE的均匀化有效弹性性能，作为Ni体积分数和RVE尺寸的函数。结果表明，通过增加Ni碎片，RVE表现出更硬的弹性行为。对于基于RSA的RVE，将Ni的体积分数从0.2 Vf增加到0.8 Vf时，泊松比降低了7%，弹性模量增加了83%。对于Al/Ni（0.8 Vf）的基于微观结构的RVE尺寸，从最大尺寸（尺寸1），长度为575μm，宽度为575μm到最小尺寸（尺寸5），长度为287.5μm，宽度为287.5μm，弹性模量和泊松比分别下降了16%和0.8%。
