Multi-Scale Modelling of Deformation and Fracture in a Biomimetic Apatite-Protein Composite: Molecular-Scale Processes Lead to Resilience at the μm-Scale.
Fracture mechanisms of an enamel-like hydroxyapatite-collagen composite model are elaborated by means of molecular and coarse-grained dynamics simulation. Using fully atomistic models, we uncover molecular-scale plastic deformation and fracture processes initiated at the organic-inorganic interface. Furthermore, coarse-grained models are developed to investigate fracture patterns at the μm-scale. At the meso-scale, micro-fractures are shown to reduce local stress and thus prevent material failure after loading beyond the elastic limit. On the basis of our multi-scale simulation approach, we provide a molecular scale rationalization of this phenomenon, which seems key to the resilience of hierarchical biominerals, including teeth and bone.
Lehrstuhl für Theoretische Chemie / Computer Chemie Centrum, Friedrich-Alexander Universität Erlangen-Nürnberg, Nägelsbachstraße 25, 91052 Erlangen, Germany.
Dirk
D
Zahn
Lehrstuhl für Theoretische Chemie / Computer Chemie Centrum, Friedrich-Alexander Universität Erlangen-Nürnberg, Nägelsbachstraße 25, 91052 Erlangen, Germany.
Patrick
P
Duchstein
D001031:Apatites; D001696:Biomechanical Phenomena; D040761:Biomimetic Materials / Q000737:chemistry; D032701:Biomimetics; D003094:Collagen / Q000737:chemistry*; D003743:Dental Enamel / Q000737:chemistry*; D003764:Dental Materials / Q000737:chemistry*; D017886:Durapatite / Q000737:chemistry*; D004548:Elasticity; D008422:Materials Testing; D056004:Molecular Dynamics Simulation; D013314:Stress, Mechanical; D016474:Weight-Bearing
D001031:Apatites; D003764:Dental Materials; D003094:Collagen; D017886:Durapatite