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This research focused on testing the effect of the negative Poisson’s ratio of a carbon fiber composite on its critical buckling load. A secondary goal was to determine the accuracy of simulation compared to the experimental results for carbon fiber composites. In order to accomplish these two goals, both simulation and experimental testing were employed. For the simulation, ABAQUS software was used to determine predicted values for the critical buckling loads of auxetic and nonauxetic composites as well as the respective nonlinear force behavior of these composites. These results were then compared to experimental results of four auxetic and four non-auxetic specimens each experiencing uniaxial compressive tests. The results of simulation and experimentation showed that the critical buckling loads, and force sustained in general, of the auxetic composites were about three times higher than those of non-auxetic composites. While it appears that the negative Poisson’s ratio has a significant impact on the buckling strength of composite materials, further testing is required to determine the effects of other factors on the critical buckling loads. Along with this, the simulation was more accurate for the auxetic composites than for the non-auxetic composites. Therefore, further testing and simulation are required to determine the limits of simulation accuracy for composite structures.
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Tension buckling and postbuckling of nanocomposite laminated plates with in-plane negative Poisson’s ratio
Abstract Mechanical metamaterials with negative Poisson’s ratio (NPR) have emerged as a novel class of engineering material, and have attracted increasing attention in various engineering sectors. Most studies available on the buckling problem of laminated plates with positive or NPR are those under uniaxial compression. Here, we report that the buckling phenomenon may occur for auxetic nanocomposite laminated plates under uniaxial tension when the unloaded edges of the plates are immovable. Two types of nanocomposites are considered, including graphene/Cu and carbon nanotube/Cu composites. Governing equations of the auxetic nanocomposite laminated plates are formulated based on the framework of Reddy’s higher-order shear deformation theory. In modeling, the von Kármán nonlinear strain–displacement relationship, temperature-dependent material properties, thermal effects, and the plate–substrate interaction are considered. The explicit analytical solutions for postbuckling of auxetic nanocomposite laminated plates subjected to uniaxial tension are obtained for the first time by employing a two-step perturbation approach. Numerical investigations are performed for tension buckling and postbuckling behaviors of auxetic nanocomposite laminated rectangular plates with in-plane NPR rested on an elastic substrate under temperature environments.
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- Award ID(s):
- 2202737
- PAR ID:
- 10513034
- Publisher / Repository:
- De Gruyter
- Date Published:
- Journal Name:
- Nanotechnology Reviews
- Volume:
- 13
- Issue:
- 1
- ISSN:
- 2191-9097
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1515/ntrev-2023-0173
