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Title: MECHANICAL BEHAVIOR MODELING OF UNIDIRECTIONAL CARBON FIBER REINFORCED POLYMER COMPOSITES REINFORCED WITH Z-DIRECTIONAL NANOFIBERS
This paper utilizes a periodic unit cell modeling technique combined with finite element analysis (FEA) to predict and understand the mechanical behaviors of a nanotechnology-enhanced carbon fiber reinforced polymers (CFRPs) composite. This research specifically focuses on the study of novel Z-threaded CFRPs (ZT-CFRPs) that are reinforced not only by unidirectional carbon fibers but also with numerous carbon nanofibers (CNFs) threading through the CFRP laminate in the z-direction (i.e., through-thickness direction). The complex multi-scaled orthogonally-structured carbon reinforced polymer composite is modeled starting from a periodic unit cell, which is the smallest periodic building-block representation of the material. The ZT-CFRP unit cell includes three major components, i.e., carbon fibers, polymer matrix, and carbon nanofiber Z-threads. To compare the mechanical behavior of ZT-CFRPs against unmodified, control CFRPs, an additional unit cell without CNF reinforcement was also created and analyzed. The unit cells were then meshed into finite element models and subjected to different loading conditions to predict the interaction among all their components. The elastic moduli of both unit-cells in the z-direction were calculated from the FEA data. By assuming the CNFs have the same mechanical properties of T-300 carbon fiber, the numerical modeling showed that the ZT-CFRPs exhibited a 14% improvement in z-directional elastic modulus due to the inclusion of 1 wt% CNF z-threads, indicating that ZT-CFRPs are stiffer compared to control CFRPs consisting of T-300 carbon fibers and epoxy.  more » « less
Award ID(s):
1748369
NSF-PAR ID:
10075360
Author(s) / Creator(s):
Date Published:
Journal Name:
International SAMPE Symposium and Exhibition
ISSN:
0891-0138
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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