Superman Suit:
Futuristic Body Armor
Presented By:
Jonathan Boulanger
Emma Lecours
Sarah Xu
Megan Swain
Outline
Current bulletproof vests
 Why put carbon nanotubes in bulletproof
vests?
 Experimental testing
 Extension to macroscopic
 Conclusion

Current Bullet-Proof Vests
• Made of layered fibrous material
• Absorbs and disperses the energy of the projectile
• Slows and stops the bullet
Current Materials
• Kevlar
• Many strong bonds
between chains
• Twaron
• nearly identical chemical structure to Kevlar
• Dyneema (Ultra high molecular weight polyethylene)
• extremely long polymer chains (n>100 000)
• load transferred to polymer backbone
Problems with Current Bullet-Proof
Vests
• Wearer is forced to absorb the energy of the
projectile
• Blunt force trauma can occur
• wind knocked out of the wearer
• bruising of the skin
• injuries to the internal organs (possibly
fatal)
• Superior vest would deflect the energy of
the bullet away from the wearer
Why Carbon Nanotubes?
High modulus of elasticity (~1 TPa)
 High strain to yield (up to 40% in tensile)
 Multiple deformation modes:


Elongation of hexagonal structure
 High defect mobility of 5-7 ring defects


Stepwise diameter reduction
Tube collapse
 Necking
Carbon Nanotube Deformation
[2]
Experimental Procedure
Computer simulation to model nanotube
deformation
 Uses Tersoff-Brenner potential
 Diamond bullet

Maximum absorption energy
Highest in center of fixed end CNT
 Does not vary significantly with radius
 Varies linearly with length of nanotube

Absorption Energy
Bounce back time the same
 Needs 12.5ps to ‘recover’

Extension to Macroscopic
Applications
•Variations in atomic structure of CNTs
with same diameters only depend on
their different lengths.
•Macroscopic response can be
approximated from microscopic
calculations.
•A revolver bullet typically has a damage
area of 0.652 cm^2 and energy of 320J.
•If a bundle (yarn) has a 100 μm
diameter (5 X 10^9 nanotubes ), it should
be able to absorb 0.344J.
•Therefore 6 layers of woven fabric
composed of 180 nanotube yarns
(0.9cm) will be sufficient, which
corresponds to a thickness of 600 μm
Conclusions

Carbon nanotubes have great potential
 Large
capacity to store elastic energy without
deforming
 Repeated impacts possible (12.5 ps limit)
Only computer simulations so far
 According to assumptions, will scale well
into the macroscale
 If assumptions hold, 600 μm woven CNT
yarns will be sufficient to repel bullets

References
1.
2.
Ajayan, P. M. (1999). Nanotubes from carbon. Chemical Reviews,
99(7), 1787.
Mylvaganam, K., & Zhang, L. C. (2007). Ballistic resistance
capacity of carbon nanotubes. Nanotechnology, 18(47), 475701.
Questions?