Size-Effect on the Mechanical Properties of Nanowires via Boundary Cauchy-Born Method

In this paper a novel multi-scale method for modelling boundary and size effects has been proposed and their effects on mechanical properties of nanowires have been investigated. Boundary Cauchy-Born (BCB) method which is based on Cauchy-Born (CB) rule is capable of computing the accurate strain and stress states in whole of the continuous medium especially in its boundaries. In order to solve real problems with this new method, it has to be merged with Finite Element method (FEM) in which the stress and strain of quadratures are computed from CB rule. In other world, the quadratures indicate the real atomistic behavior. Since BCB shows accurate results in whole of the continua, mechanical properties of nanowires which are strongly dependent on their size and surface to volume ratio are studied via BCB method.

Keywords:

Boundary Cauchy-Born , Finite Element , Nanowire , Size-effect