Lecture
Natural architectured materials and mechanical adaptation
Natural architectured materials and mechanical adaptation
Biological materials are natural hybrids due to the assembly of nanometric, micrometric and even larger building blocks. The complexity of their arrangement confers these materials a broad functional diversity [1], but also leads to considerable material inhomogeneities. However, in many instances, the interfaces between building blocks are not weakening the material but rather enhance its fracture resistance, based on a tessellation of comparably brittle building blocks [2]. Periodic inhomogeneities in Young's modulus hinder crack propagation [3] and improve the toughness of the material. In bone, for example, a plywood-like lamellar arrangement of mineralized collagen fibrils leads to an improvement of both strength and toughness as compared to a homogeneous material with identical average properties.
[1] M. Eder, S. Amini, P. Fratzl, Science 362, 543-547 (2018)
[2] P. Fratzl, O. Kolednik, F. D. Fischer, M. N. Dean, Chem. Soc. Rev. 45, 252 - 267 (2016)
[3] F.D. Fischer, O. Kolednik, J. Predan, H. Razi, P. Fratzl, Acta Biomaterialia 55, 349-359 (2017).
[4] H. Razi, J. Predan, F. D. Fischer, O. Kolednik, P. Fratzl, Bone 130, 115102 (2020).
