Abstract: Using SC potential, molecular dynamic simulation is made under three conditions such as volume expansion, tensile deformation and shear deformation. Then three independent elastic constants of FCC crystal such as Ag, Au, Cu, Ni, Pd and Pt are obtained. Under different scale models the elastic constants are almost same, which shows the calculation method is successful. The calculated result agrees with the experimental one very well. Then the applicability of these elastic constants to nanodevices is analyzed here. The conclusion indicates that the calculated elastic constants can not be used directly to nanodevices of tiny size because of size effect. At the same time, when the nanodevices is big enough, these elastic constants should work well.

Key words: Applicability, Elastic constants, FCC crystal, Molecular dynamic, Size effect