TY - JOUR
T1 - On the rate dependence of mechanical properties of aligned carbon nanotube arrays
AU - Lu, Y. C.
AU - Zhang, Q.
AU - Dai, L.
AU - Baur, J.
N1 - Funding Information:
This work has been supported by grants from United Technology Corporation, the Kentucky NASA EPSCoR RIA program, and the Kentucky Science and Engineering Foundation (KSEF) RDE program.
Publisher Copyright:
© 2015, Springer Science+Business Media Dordrecht.
PY - 2015/8/1
Y1 - 2015/8/1
N2 - Aligned carbon nanotube arrays are a new form of carbon nanomaterials that have received great interest due to their superior structure and properties. The present work comprehensively examines the rate-dependent mechanical deformation of the vertically aligned carbon nanotube arrays (VA-CNTs) by the use of indentation tests. The small-displacement, elastic property of the VA-CNTs was measured by a spherical indenter. The effective indentation strain rate was varied by adjusting the indenter unloading rate. The instantaneous modulus of the VA-CNTs has been calculated and is found to increase linearly with indentation strain rate. The large-displacement, plastic property of the VA-CNTs was measured by a cylindrical, flat-ended indenter. At large indentation depths, the stress–strain curve of the VA-CNTs reveals distinct plastic deformation. The indentation strain rate was varied by directly changing the indenter velocity. The yield strength (σy) of the VA-CNTs also increases linearly with respect to indentation strain rate.
AB - Aligned carbon nanotube arrays are a new form of carbon nanomaterials that have received great interest due to their superior structure and properties. The present work comprehensively examines the rate-dependent mechanical deformation of the vertically aligned carbon nanotube arrays (VA-CNTs) by the use of indentation tests. The small-displacement, elastic property of the VA-CNTs was measured by a spherical indenter. The effective indentation strain rate was varied by adjusting the indenter unloading rate. The instantaneous modulus of the VA-CNTs has been calculated and is found to increase linearly with indentation strain rate. The large-displacement, plastic property of the VA-CNTs was measured by a cylindrical, flat-ended indenter. At large indentation depths, the stress–strain curve of the VA-CNTs reveals distinct plastic deformation. The indentation strain rate was varied by directly changing the indenter velocity. The yield strength (σy) of the VA-CNTs also increases linearly with respect to indentation strain rate.
KW - Aligned carbon nanotube arrays
KW - Large-displacement indentation
KW - Nanoindentation
KW - Strain rate
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U2 - 10.1007/s11043-015-9261-0
DO - 10.1007/s11043-015-9261-0
M3 - Article
AN - SCOPUS:84938415885
SN - 1385-2000
VL - 19
SP - 229
EP - 242
JO - Mechanics of Time-Dependent Materials
JF - Mechanics of Time-Dependent Materials
IS - 3
ER -