@Article{cmc.2013.038.031,
AUTHOR = {J.B. Niu,  L.L. Li, Q. Xu, Z.H. Xia},
TITLE = {Toughening Mechanisms in Carbon Nanotube-Reinforced Amorphous Carbon Matrix Composites},
JOURNAL = {Computers, Materials \& Continua},
VOLUME = {38},
YEAR = {2013},
NUMBER = {1},
PAGES = {31--41},
URL = {http://www.techscience.com/cmc/v38n1/22706},
ISSN = {1546-2226},
ABSTRACT = {Crack deflection and penetration at the interface of multi-wall carbon nanotube/amorphous carbon composites were studied via molecular dynamics simulations. In-situ strength of double-wall nanotubes bridging a matrix crack was calculated under various interfacial conditions. The structure of the nanotube reinforcement -ideal multi-wall vs. multi-wall with interwall <i>sp</i><sup>3</sup> bonding - influences the interfacial sliding and crack penetration. When the nanotube/matrix interface is strong, matrix crack penetrates the outermost layer of nanotubes but it deflects within the nanotubes with certain <i>sp</i><sup>3</sup> interwall bond density, resulting in inner wall pullout. With increasing the <i>sp</i><sup>3</sup> interwall bond density, the fracture mode becomes brittle; the fracture energy decrease while the bridging strength increases and then decreases. Our results suggest that the outermost nanotube wall can serve as a sacrificial layer such that the interface may be designed by effectively putting it inside the nanotubes. Controlling the density of <i>sp</i><sup>3</sup> interwall bond within the multiwall carbon nanotube makes the transition from brittle to tough failure modes in the composites even when the matrix/nanotube interface is strong.},
DOI = {10.3970/cmc.2013.038.031}
}