SIZE EFFECT ON THE ELASTIC MODULUS OF NANOMATERIALS AS MEASURED BY RESONANT CONTACT AFM
S. Cuenot, S. Demoustier-Champagne, C. Frétigny and B. Nysten
Université catholique de Louvain, BE
Keywords: polymer nanotubes, metallic nanowires, elastic modulus, AFM, size effects
The elastic modulus of metallic nanowires and polymer nanotubes was measured using a novel method called resonant contact atomic force microscopy. The direct application of a normal load to the contact was obtained using a sinusoidal electric field applied between the sample holder and the microscope head, that induces the cantilever vibration. This method also enabled the characterization of the mechanical behavior of the nanomechanical systems and the determination of the boundary conditions of the nanostructures (clamping conditions). It is shown that the measured elastic modulus increases with decreasing diameter. This increase can be explained both in terms of a better structural perfection in the smaller nanostructures and in terms of surface effects due to the higher surface to volume ratio in the smaller nanowires or nanotubes.
NSTI Nanotech 2003 Conference Technical Program Abstract