Numerical investigation of mechanical behaviour of nanocrystalline copper

The effect of grain size on the overall elastic and plastic properties of nanocrystalline materials has been evaluated using the elastoplastic finite element method. The tensile deformation behaviour of nanocrystalline copper(based on a unit cell model comprising 2-100 nm sized copper crystallites and 1 nm wide grain boundaries) has been analysed. Assuming that the material is elastic-perfect plastic (because of the very fine grain size), it has been shown that the yield stress increases and the elastic modulus decreases with a decrease in grain size. These results are consistent with the reported experimental observations. This analysis can be used effectively to predict the mechanical behaviour of any type of nanocrystalline material.