Mechanics of fragmentation of crocodile skin and other thin films

Qin, Zhao and Pugno, Nicola and Buehler, Markus J. (2014) Mechanics of fragmentation of crocodile skin and other thin films. In «Scientific Reports», vol. 4, n. 4966 London, UK : Nature Publishing Group, pp. 1-7.

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    Fragmentation of thin layers of materials is mediated by a network of cracks on its surface. It is commonly seen in dehydrated paintings or asphalt pavements and even in graphene or other two-dimensional materials, but is also observed in the characteristic polygonal pattern on a crocodile’s head. Here, we build a simple mechanical model of a thin film and investigate the generation and development of fragmentation patterns as the material is exposed to various modes of deformation. We find that the characteristic size of fragmentation, defined by the mean diameter of polygons, is strictly governed by mechanical properties of the film material. Our result demonstrates that skin fragmentation on the head of crocodiles is dominated by that it features a small ratio between the fracture energy and Young’s modulus, and the patterns agree well with experimental observations. Understanding this mechanics-driven process could be applied to improve the lifetime and reliability of thin film coatings by mimicking crocodile skin.

    Item Type: Article in journal
    FP7 Grant Agreement Number: European Research Council/StG Ideas 2011 - BIHSNAM/EU/FP7/279985, European Research Council/PoC 2013-I - REPLICA2/EU/FP7/619448, European Research Council/PoC 2013-I - KNOTOUGH/EU/FP7/632277, Graphene FET Flagship/EC/FP7/604391
    Department or Research center: Civil, Environmental and Mechanical Engineering
    Subjects: T Technology > TA Engineering (General). Civil engineering (General) > TA164 Bioengineering
    T Technology > TA Engineering (General). Civil engineering (General) > TA630 Structural Engineering
    Repository staff approval on: 15 Jan 2015 10:20

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