Determination of elastic properties of polymer nanocomposites using embedded element method

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2022-2
Altay, Aysu Elif
Composites are preferred in different industries due to their high strength and lightness. Carbon nanotube (CNT) reinforced polymer composites are preferred composites due to their superior mechanical properties. CNTs in the material increase the stiffness of the structure positively, but the presence of CNTs makes the structure heterogeneous. The objective of this study is to determine the effective elastic properties of polymer nanocomposites using the embedded element method. Due to their nanosize, finite element analysis of CNT reinforced polymer nanocomposites requires high computation power. In the embedded element method, the finite element mesh of the CNTs and the matrix do not need to be compatible, which provides convenience in modeling. Hence, the embedded element method, which is one of the modeling techniques of the Abaqus software, is selected in this study. Representative Volume Elements (RVEs) are generated, and computational homogenization analyses are conducted using the embedded element method. The results of the conventional finite element method and the embedded element method are compared. Since a single CNT in the heterogeneous structure does not accurately represent reality, models containing randomly-placed and randomly-oriented CNTs are created. The effect of small aggregation on the homogenization process is studied since CNTs tend to agglomerate due to their inherent nature. Finally, the number of minimum CNTs required in computational homogenization is determined by a numerical convergence study. Commercial finite element program Abaqus is used for all analyses in this study, and Python software is utilized to compute homogenized properties and generate RVEs.

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Citation Formats
A. E. Altay, “Determination of elastic properties of polymer nanocomposites using embedded element method,” M.S. - Master of Science, Middle East Technical University, 2022.