APPLICATION OF ATOMISTIC ELEMENT ANALYSIS IN NANO-SIMULATIONS

摘要

An atomistic finite element approach has recently been developed for nano-simulation. Two types of elements were established: chemical bond and van der Waals bond. The stiffness matrixes of these elements were formulated based upon relations between bond deformations and restoration forces or moments. Once element stiffness matrixes are established, a procedure, similar to conventional finite element analysis, can be employed to assemble a global stiffness matrix. Boundary conditions can then be applied. Thus, stress-strain relations can be derived based upon the dimension change of the atomistic material domain in response to external load. The new approach can be employed for both static and dynamic analysis. In order to demonstrate the approach, deformations of idealized polymer fields were simulated. The stress-strain curve was derived and the progressive development of damage and failure was observed step by step. In addition, stress derived from boundary conditions was compared to atomic stress.