Microstructure and Mechanical Properties of Dungeness Crab Exoskeletons

摘要

In this paper, we report our recent studies of the microstructure and mechanical properties of Dungeness crab exoskeleton. Nanoindentation and scanning probe microscopy (SEM) were carried out on different parts of the crab (claw and body shell), and different parts of the exoskeleton (exocuticle and endocuticle). Clearly defined four-layer structure was observed in the exoskeleton. In the cross sections of the claw and body shell, the mechanical properties show a decreasing trend from the exocuticle to endocuticle. In both cross sections and in-plane sections, a higher property was measured in the claw than the body shell. Finally, super low mechanical properties were obtained for nanoindentation on the in-plane sections of the claw's endocuticle than the cross-sections. The chitin-protein volume fraction was found to be the major factors affecting the mechanical properties in the different body parts as well as different layers of the exoskeleton.