MODELING OF INTERFACE STRENGTH AS WELL AS INTERFACE DEFORMATION BASED ON NANOMECHANICS AND DEVELOPMENT OF INTERFACE DATABASE SYSTEMS

Biomaterials such as bone and marine exoskeletons have primarily an organic phase (e.g. tropocollagen in bone, chitin in exoskeleton) and an inorganic phase (e.g. hydroxyapatite in bone, calcite in exoskeleton) arranged in a precisely organized multi-level hierarchical arrangement. Interfacial interactions between the organic and inorganic phases significantly affect the mechanical properties of such biomaterials. In presented study, idealized tropocollagen-hydroxyapatite and chitin-calcite interfacial systems are analyzed using a multiscale simulation framework that combines explicit three-dimensional molecular dynamics simulations with finite element simulations that take into account explicit microstructure in a three-dimensional hierarchy. The analyses focus on the shear deformation that occurs in interfaces of such materials when overall three-dimensional hierarchy is subjected to mechanical loading. In order to predict the interface stress magnitude in such systems during deformation, steered molecular dynamics simulations are performed to study the interfacial sliding process between the organic and inorganic phases at the nanoscale. A visco-plastic interfacial sliding model is used to calculate the interface strength and the shear viscosity of each interfacial system. In order to predict the effect of interface on the behavior of the material at the continuum level, a combined

Name thesis:degree_name

Doctor of Philosophy (PhD)

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Aeronautics and Astronautics

Year

2015

Author dc:creator

• Qu, Tao

Contributors dc:contributor

• Vikas Tomar
• R. Byron Pipes
• C-T Sun
• Christian Hellmich
• Jong H. Choi

• Biomaterials
• Composite Materials
• Finite Element Modeling
• Fracture Mechanics
• Interface
• Molecular Dynamics

Repository record dc:identifier

https://docs.lib.purdue.edu/open_access_dissertations/1143

OAI identifier oai:identifier

oai:docs.lib.purdue.edu:open_access_dissertations-2359