Radial elasticity of multiwalled carbon nanotubes.
We report an experimental and a theoretical study of the radial elasticity of multiwalled carbon nanotubes as a function of external radius. We use atomic force microscopy and apply small indentation amplitudes in order to stay in the linear elasticity regime. The number of layers for a given tube radius is inferred from transmission electron microscopy, revealing constant ratios of external to internal radii. This enables a comparison with molecular dynamics results, which also shed some light onto the applicability of Hertz theory in this context. Using this theory, we find a radial Young modulus strongly decreasing with increasing radius and reaching an asymptotic value of 30+/-10 GPa.
Palaci
I
I
School of Physics, Georgia Institute of Technology, 837 State Street, Atlanta, Georgia 30332, USA.
Fedrigo
S
S
Brune
H
H
Klinke
C
C
Chen
M
M
Riedo
E
E