Micromechanical analysis for bone-like nanostructural biomaterials

Shear lag analysis was applied to bone-like nanostructural biomaterials such as nacre and bone with unique structure in nano scale. The models for protein with both linear and elastic-plastic deformations were developed. Compared with the results of finite element method (FEM) and the tension shear chain model of Gao, the linear shear lag model fits better with FEM while the tension shear chain model predicts a larger effective modulus when the aspect ratio is large. The elastic-plastic shear lag model fits well with the experimental results, and the plastic deformation takes place before the modulus of the materials decreases obviously, which provides those materials the ability to dissipate energy and enhance the toughness.