Size-dependent nonlinear secondary resonance of micro-/nano-beams made of nano-porous biomaterials including truncated cube cells

Abstract

Porous biomaterials have been utilized in cellular structures in order to mimic the function of bone as a branch of tissue engineering approach. With the aid of nanoporous biomaterials in which the pore size is at nanoscale, the capability of biological molecular isolation becomes more efficient. In the present study, firstly the mechanical properties of nanoporous biomaterials are estimated on the basis of a truncated cube cell model including a refined hyperbolic shear deformation for the associated lattice structure. After that, based upon a nonlocal strain gradient beam model, the size-dependent nonlinear secondary resonance of micro/nano-beams made of the nanoporous biomaterial is predicted corresponding to the both of subharmonic and superharmonic excitations. The non-classical governing differential equation of motion is constructed via Hamilton's principle. By employing the Galerkin technique together with the multiple time-scales method, the nonlocal strain gradient frequency-response and amplitude-response of the nonlinear oscillation of micro/nano-beams made of a nanoporous biomaterial under hard excitation are achieved. It is shown that in the superharmonic case, increasing the pore size leads to enhance the nonlinear hardening spring-type behavior of jump phenomenon and the height of limit point bifurcations. In the subharmonic case, higher pore size causes to increase the gap between two branches associated with the high-frequency and low-frequency solutions.