Integrating ultrastructural diffraction imaging and multiscale modelling to unveil the nanoscale mechanics of arthropod cuticle in bending.
Yanhong Wang, Ettore Barbieri, Yi Zhang, Nick Terrill, Himadri Shikhar Gupta
Author Information
Yanhong Wang: School of Engineering and Materials Science and Institute of Bioengineering, Queen Mary University of London, London, UK.
Ettore Barbieri: Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Research Institute for Value-Added-Information Generation (VAiG), Center for Mathematical Science and Advanced Technology (MAT), 3173-25, Showa-machi, Kanazawa-ku, Yokohama, Japan. ORCID
Yi Zhang: School of Engineering and Materials Science and Institute of Bioengineering, Queen Mary University of London, London, UK.
Nick Terrill: Diamond Light Source, Harwell Science and Innovation Campus, Didcot, UK.
Himadri Shikhar Gupta: School of Engineering and Materials Science and Institute of Bioengineering, Queen Mary University of London, London, UK. ORCID
Determining the mechano-structural relations in biological materials with hierarchical structure is crucial to understanding natural optimization strategies and designing functional bioinspired composites. However, measuring the nanoscale mechanics and dynamic response is challenging when the specimen geometry and loading environment are physiologically complex. To overcome this challenge, we develop a combination of synchrotron X-ray diffraction testing and analytical modelling to explore the mechano-structural changes during bending loads on stomatopod cuticle. Stomatopod cuticle is an example of a hierarchical biomaterial optimized for high impact and bending resistance. Using models for large deformations of elastic continua, we measure cuticle strains from macroscopic deformations and combine diffraction-based fibril strains with stresses to quantify the local elastic moduli and nanoscale strain concentration factors, which are found to vary across cuticle sub-regions and under different flexion loading modes. This approach has the advantage of identifying constituent biomaterial properties and mechanisms and is also suitable for studying time-dependent changes, such as concurrent strains of the nanofibrous phase that occur during physiological loading.
