Basic study of biomimetic composite materials in the forewings of beetles

Inspired by bio-structures in optimal materials design, the microstructures and bio-structure design techniques in the forewing of the Allomyrina dichotoma beetle were examined in order to improve upon engineering designs. From this study, the following results were obtained: The fiber volume fraction and the shape of the fiber cross-section in the forewing depend on the forewing's position, while the shape of the cross-section is square or circular when fiber content is high or low, respectively. Within the laminated layers of the forewing's chitin fibers, fibers cross-link to form a reticular structure, thus providing two-dimensional strength and cleverly avoiding the common weakness found in woven fibers due to the physical strain caused by fiber overlap and bend. Between the laminated layers, the beetle's forewing is three-dimensionally reinforced by trabecular structures. In this study, both biomimetics composite materials and their design techniques are discussed. (C) 2007 Published by Elsevier B.V.