Identification of Deformation Mechanisms in Biomaterials Through AFM and Digital Image Correlation

  • Horacio D. EspinosaEmail author
Conference paper
Part of the Conference Proceedings of the Society for Experimental Mechanics Series book series (CPSEMS)


Most biological composite materials achieve higher toughness without sacrificing stiffness and strength. Interrogating how Nature employs these strategies and decoding the structure-function relationship of these materials is a challenging task that requires knowledge about the actual loading and environmental conditions of the material in their natural habitat, as well as a complete characterization of their constituents and hierarchical ultrastructure. In this work, we present an experimental framework that combines in situ and ex situ fracture testing with digital image correlation to allow the identification and quantification of toughening mechanisms involved during fracture of natural systems. We present this methodology in two case studies: (1) pangolin scales, and (2) nacre from seashells. We envision that the outcome of this research will pave the way for more bio-inspired design systems that can subsequently shed light on how Nature has evolved materials to optimize mechanical properties.


Biomaterials Bioinspired materials Digital image correlation Atomic force microscope Nacre Pangolin 


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© The Society for Experimental Mechanics, Inc. 2019

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringNorthwestern University Technological InstituteEvanstonUSA

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