ABSTRACT
This conclusion presents some closing thoughts on the concepts covered in the preceding chapters of this book. The book provides some modest solution approach to the unsolved question about the correlation of the ultra/nano-structure and nano to micro to macro-mechanical properties of the natural materials. It discusses the hierarchical and functionally graded microstructures that exist in natural materials such as bone, teeth, hair, scale, and shell. The book then describes how the nanomechanical properties of human cortical bone are dependent on locations, direction of orientation, density, state of hydration, loading conditions, age, and gender. It also discusses the role of dentine-enamel junction (DEJ) in modeling of fracture toughness. The book investigates the nanoindentation induced creep behavior of tough dentine and hard enamel. It then reviews nanoindentation of hair fiber. The book also investigates both nano-tribological and nano-mechanical properties of normal, virgin-bleached, and Fe tannin salt-treated human hairs. It examines the detail nanomechanical properties of shells and scales.
