Optimizing load transfer in multiwall nanotubes through interwall coupling: Theory and simulation

Bending behavior of double-walled carbon nanotubes with sp3 interwall bonds

“…It is clearly seen that the bending behaviors of DWCNTs with sp 3 bonds are not only dependent of the sp 3 bonds density, but also on their distribution patterns (or more precisely, the number of sp 3 bonds at the compressed side of DWCNTs). This observation is in agreement with Byrne et al 30 findings. By employing an analytical shear lag model for MWCNTs under tensile loading, Byrne et al 30 found that optimal load transfer can be realized when sp 3 bonds is uniformly distributed axially, and all interwall regions have the same shear stiffness.…”

“…This observation is in agreement with Byrne et al 30 findings. By employing an analytical shear lag model for MWCNTs under tensile loading, Byrne et al 30 found that optimal load transfer can be realized when sp 3 bonds is uniformly distributed axially, and all interwall regions have the same shear stiffness. In this study, the sp 3 bonds under consideration are uniformly distributed in an array along the length as shown in Fig.…”

“…This may be the main reason why researchers in the literature adopted randomly distributed sp 3 bonds to investigate their effects on the axially loaded MWCNTs. 7,8,14,15,29,30 IV. CONCLUSIONS…”

Optimizing strength and toughness of nanofiber-reinforced CMCs

“…The effective elastic modulus for a multiwall carbon nanotube when treated as full solid cylindrical nanofiber with the same outer radius r is E f ¼ E CNT ðr 2 Àr 2 i Þ=r 2 , which accounts for the pore space inside the inner radius r i . We consider an 18-wall MWCNT with external radius r¼129Å and inner radius r i ¼70Å with the walls coupled by irradiation-induced sp 3 bonds so that there is adequate internal load transfer among walls (Byrne et al, 2010;Peng et al, 2008), so E f ¼705 GPa. We use a nanotube strength of s CNT ¼58 GPa, as measured by Peng et al (2008) at a length of L 0 ¼2000 nm.…”

The roles of crosslinks in the buckling behaviors and load transferring mechanisms of double-walled nanotubes under compression

“…Peng et al [11,20] conducted further computational works to complement experimental efforts and demonstrated that irradiation induced crosslinks can be used to tailoring the load carrying capacity of MWNTs by varying the types and densities of defects. Byrne et al [21,22] showed that the superior mechanical properties of MWNTs can be realized by controlling sp 3 inter-wall bonds. and outer shells of MWNTs, most of these results are achieved under tensile loading conditions and there are relatively few studies on the compressive buckling behavior.…”