Multiscale Microstructure of Chafer Cuticle
The observation of scanning electron microscope (SEM) shows chafer cuticle is a kind of biocomposite which possesses multiscale microstructural characteristic. Under a relative small magnification of the SEM, it is found that the cuticle consists of chitin-fiber layers and protein matrix and that the fibers in two adjacent fiber layers have different directions, which composes a kind of fiber-crossed microstructure. Under a relative large magnification, it is observed that the many chitin fibers in the crossed fiber layers are furcated fibers, which exhibits a kind of fiber-furcated microstructure. The maximum pullout force of the fiber-furcated microstructure is investigated and compared with that of the fiber-non-furcated microstructure through their representational models. It shows that the maximum pull out force of the fiber-furcated structure is distinctly larger than that of the fiber-non-furcated structure.