The microstructure of wood is highly anisotropic, which suggests that this material could exhibit unusual elastic properties. A few studies have suggested the possibility of auxeticity, or negative Poisson’s ratio (NPR) in some wood samples. In order to conclusively confirm that wood does show NPR, we have used a combination of geometric modelling, finite element analysis (FEA) and off-axis compression testing. The geometric model indicates that idealised thin-walled wood cell structures should generate NPR of -1, FEA suggests that more realistic cell arrays can attain NPR, to -0.27, and compression tests show that some NPR –to -0.74– remains in real wood samples. These results could help design “engineered-wood” laminates products with tailored elastic properties.
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