Copyright © 2014 Tech Science Press CMC, vol.42, no.1, pp.63-73, 2014 Finite Element Modeling of Compressive Deformation of Super-long Vertically Aligned Carbon Nanotubes J. Joseph 1 and Y. C. Lu 1 Abstract: The super-long, vertically aligned carbon nanotubes (SL-VACNTs) are novel carbon nanomaterial produced from template-free synthesis. The me- chanical responses of such material have been investigated by continuum finite element modeling and compared with experimental observations. The crushable foam model has been adequate in modeling the stress-strain curve and deformation of the SL-VACNTs under compression. SL-VACNTs are seen to exhibit transient elastic deformation at small displacement and then plastic deformation at large dis- placement. The deformation mostly occur at the position immediately beneath the compression platen (indenter face) due to the high stress/strain concentrations. Keywords: Vertically aligned carbon nanotubes, Stress-strain, Finite element mod- eling, Compression. 1 Introduction Vertically aligned carbon nanotubes (VACNTs) have been generally synthesized with the aids of various templates. Terrones et al. have grown the first VACNTs by depositing the carbon sources in linear tracks in a silica template [Terrones et al. (1997)]. de Heer et al. have made the carbon nanotubes through the use of an aluminum oxide micropore filter, a template used to align the nanotubes [de Heer et al. (1995)]. Recently, template-free synthesis has been used to produce the VAC- NTs [Ishigami et al. (2008); Bajpai et al. (2004); Chen et al. (2010)]. In a typical template-free synthesis, hydrocarbon vapor is passed through a high temperature reaction chamber in which a catalyst material has been introduced. Decomposi- tion of hydrocarbon would take place, which leads to the formation /growth of nanotubes. Compared the template synthesis, the template-free synthesis is more effective in producing larger scale and taller nanotubes, so called super-long VAC- NTs (SL-VACNTs). 1 Department of Mechanical Engineering, University of Kentucky, Lexington, KY, U.S.A.