Department of Mechanical Engineering
Kenneth E. Goodson
Won, Y., Gao, Y., Panzer, M.A., Dogbe, S., Pan, L., Kenny, T.W., and Goodson, K.E., 2012, "Mechanical Characterization of Aligned Multi-Wall Carbon Nanotube Films," Carbon, Vol. 50, pp 347-355.
Owing to their unique mechanical and thermal properties, vertically aligned carbon nanotube
(VACNT) films are promising for use as advanced thermal interface materials. While
there has been much research on the thermal properties of VACNT films, the mechanical
modulus along the in-plane direction has received little attention. This paper reports a
new technique for measuring this property using the resonant frequency shift in microfabricated resonators integrated with VACNT films. A comprehensive description of the technique includes microfabrication details, the laser Doppler methodology for extracting the
resonant frequency, uncertainty analysis, and a model for data interpretation. A model
accounting for the spatial variation of nanotube alignment relies on electron microscopy
data and is consistent with the strong thickness dependence of the modulus data. The
modulus of 0.5–100 lm-thick multi-walled nanotube films varies from 8 to 300 MPa, which
is a promising value for a variety of applications including thermal interfaces.