Abstract
Nacre, the inner layer of mollusk shells is a composite made of platelets of mineral aragonitic calcium carbonate with a few weight percent organic material sandwiched in between. The organic and nanostructural nuances are often suggested to be the reason for the extreme toughness of nacre. Here we report the presence of interlocks between platelets of nacre from red abalone. We also report and show, using three-dimensional finite element modeling, that interlocks are the key mechanism for the high toughness and strength of nacre. The observed rotation between platelet layers, which were earlier reported as defects of structure, are necessary for the formation of interlocks.
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References
N.J. Watabe: Studies on shell formation. XI. Crystal-matrix relationships in the inner layers of mollusk shells. Ultrastruc. Res. 12, 351 (1965).
M. Sarikaya, J. Liu, and I.A. Aksay: Nacre: Properties, crystallography, morphology, and formation, in Biomimetics: Design and Processing of Materials, edited by M. Sarikaya and I.A. Aksay (American Institute of Physics, New York, NY, 1995), pp. 35–90.
J.D. Currey: Mechanical properties of mother of pearl in tension. Proc. R. Soc. London, Ser. B. Biol. Sci. 196, 443 (1977).
A.P. Jackson, J.F. Vincent, and R.M. Turner: The mechanical design of nacre. Proc. R. Soc. London, Ser. B. Biol. Sci. 234, 415 (1988).
T.E. Schaeffer, C. Ionescu-Zanetti, R. Proksch, M. Fritz, D.A. Walters, N. Almqvist, C.M. Zaremba, A.M. Belcher, B.L. Smith, G.D. Stucky, D.E. Morse, and P.K. Hansma: Does abalone nacre form by heteroepitaxial nucleation or by growth through mineral bridges? Chem. Mater. 9, 1731 (1997).
F. Song, X.H. Zhang, and Y.L. Bai: Microstructure and characteristics of the organic matrix layers of nacre. J. Mater. Res. 17, 1567 (2002).
R.Z. Wang, Z. Suo, A.G. Evans, N. Yao, and I.A. Aksay: Deformation mechanisms in nacre. J. Mater. Res. 16, 2485 (2001).
K.S. Katti, D.R. Katti, J.P. Tang, S.M. Pradhan, and M. Sarikaya: Modelling mechanical responses in a laminated biocomposite, Part II: Nonlinear responses and nuances of nanostructure. J. Mater. Sci. 40, 1749 (2005).
D.R. Katti, S.M. Pradhan, and K.S. Katti: Modeling the organic–inorganic interfacial nanoasperities in a model bio-nano-composite, nacre. Rev. Adv. Mater. Sci. 6, 162 (2004).
J.B. Park and R.S. Lakes: Structure property relationships of biological materials, in Biomaterials: An Introduction, 2nd ed. (Plenum Press, New York, 1992), pp. 185–222.
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Katti, K.S., Katti, D.R., Pradhan, S.M. et al. Platelet interlocks are the key to toughness and strength in nacre. Journal of Materials Research 20, 1097–1100 (2005). https://doi.org/10.1557/JMR.2005.0171
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DOI: https://doi.org/10.1557/JMR.2005.0171