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1N A S AN A S A L a R CL a R C
ENABLING TECHNOLOGIES FORENABLING TECHNOLOGIES FORAEROSPACE MISSIONS - The CaseAEROSPACE MISSIONS - The Casefor for N a n o t u b e sN a n o t u b e s
Mia SiochiAdvanced Materials and Processing BranchNASA Langley Research CenterHampton, Virginia
FEL Users/Laser Processing Consortium MeetingJefferson LabMarch 11, 2004
2N A S AN A S A L a R CL a R C
Long Term GoalsLong Term Goals• Create a virtual presence throughout our solar system and
probe deeper into the mysteries of the universe and life onEarth and beyond
• Conduct human and robotic missions to planets and otherbodies in our solar system to enable human expansion
• Provide safe and affordable space access, orbital transferand interplanetary transportation capabilities to enableresearch, human exploration and commercialdevelopment of space
• Develop cutting edge aeronautics and space systemstechnologies to support highway in the sky, smart aircraftand revolutionary space vehicles
3N A S AN A S A L a R CL a R C
n Nanostructures: 20 timesstronger than steel alloys at1/6 the weight
n Active flow control
n Distributed propulsion
n Electric propulsion,advanced fuel cells, high-efficiency electric motors
n Integrated advanced controlsystems and informationtechnology
n Central “nervous system”and adaptive!vehicle control
n Develop light, strong, andstructurally efficient airvehicles.
n Improved aerodynamicefficiency.
n Design fuel-efficient, low-emission propulsionsystems.
n Develop safe, fault-tolerantvehicle systems.
Today’s Challenges: Technology Solutions:
Revolutionary VehiclesRevolutionary Vehicles–– TechnologiesTechnologies
Fuel Cell Propulsion
Active Flow Control
Adaptive Control
Nanotube
4N A S AN A S A L a R CL a R C
Future Possibilities:Today’s Challenges:
n Long-duration and large,long-haul transportation
n High-speed commercialtransportation
n Quiet and efficient runway-independent aircraft
n Autonomous operationscapability
n Months aloft athigh-altitudesand longdistances
n Quiet, efficient,affordablesupersonic flight
n Extremely shorttakeoff andlanding–doorstep-to-doorstep
n Intelligentflight controls,micro-vehiclesto transports
RevolutionaryVehiclesRevolutionaryVehicles–– Capabilit iesCapabilit ies
5N A S AN A S A L a R CL a R C
A p o l l o Space Shuttle
Space VehiclesSpace Vehicles–– TechnologiesTechnologies
G a l i l e o
Unmanned Missions
Spirit & Opportunity
Manned Missions
6N A S AN A S A L a R CL a R C
Future Possibilities:Today’s Challenges:
n Low cost access to space
n Radiation resistance
n Resilience and long termdurability
n Advance power andpropulsion technologies
n Autonomous operationscapability
Revolutionary SystemsRevolutionary Systems–– Capabilit iesCapabilit ies
7N A S AN A S A L a R CL a R C
Critical Technologies Required toAchieve Goals
• Vehicle primary and secondary structures• Radiation protection• Propulsion and power systems• Fuel storage• Electronics and devices• Sensors and science instruments• Medical diagnostics and treatment
8N A S AN A S A L a R CL a R C
Comparison of Material PropertiesComparison of Material Properties
~ 6 x 104
50
1.8
300
5.5
1.78
IM7Carbon
Fiber
~ 6 x 105
121
10
73
0.46
2.83
Aluminum2219-T87
2000Thermal Conductivity, W/m/K
1 x 109Electrical Conductivity, S/m
15Elongation, %
1030Tensile Modulus, GPa
> 30Tensile Strength, GPa
1.36Density, g/cm3
CarbonNanotubes
(CNT)P r o p e r t y
9N A S AN A S A L a R CL a R C
1 0
1 0 0
1 0 0 0
1 1 0 1 0 00 . 1
S p e c i f i cM o d u l u sG p a/ ( g / c3)
Specific Strength, G p a/ ( g / c3)
Properties of Materials for Vehicle StructureProperties of Materials for Vehicle Structure
0.2 0.5 2 5 20 50
20
50
200
500
Al 2219
Al Foam
M46J CFRP
Ti Foam Sand
Al2O3/Al
BeAl SiC/Be
M46J
Nt/Al
Nt/P
IM7
SWNT
Baseline Materials 5 - 10 years (TRL = 4 - 6) 10 - 20 years + (TRL = 1 - 3)
IM7 CFRP (TRL=4-9)
TiAl
10N A S AN A S A L a R CL a R C
High Electrical Conductivity for EffectiveHigh Electrical Conductivity for EffectiveElectrostatic Charge DissipationElectrostatic Charge Dissipation
r=10-6 (v-vc)1.5
REQUIREMENTFOR ANTI-STATIC
Park et al., Chem. Phys. Lett., accepted
11N A S AN A S A L a R CL a R C
Multifunctionality Multifunctionality as a Route to Structuralas a Route to StructuralWeight ReductionWeight Reduction
Materials Division N A S AN A S A L a R CL a R C
Emerging Materials Technologiesfor Propulsion and Power Applications
Emerging Materials TechnologiesEmerging Materials Technologiesfor Propulsion and Power Applicationsfor Propulsion and Power Applications
Carbon Nanotube P o l y me r s
Boron NitrideNanotube A l l o y s
Silicon CarbideNanotube C e r a mi c s
NASA GRC
13N A S AN A S A L a R CL a R C
Single-Walled Carbon Single-Walled Carbon Na n o t ub e sNa n o t ub e sFor Chemical SensorsFor Chemical Sensors
Single Wall Carbon Nanotube
• Every atom in a single-walled nanotube(SWNT) is on the surface and exposed toenvironment
• Charge transfer or small changes in thecharge-environment of a nanotube can causedrastic changes to its electrical properties
NASA ARC
14N A S AN A S A L a R CL a R C
• Four-level CNT dendritic neural tree with 14 symmetric Y-junctions• Branching and switching of signals at each junction similar to what happens in
biological neural network• Neural tree can be trained to perform complex switching and computing functions• Not restricted to only electronic signals; possible to use acoustic, chemical or thermal
signals
NASA ARC
Nanotube Nanotube Based ComputingBased Computing
15N A S AN A S A L a R CL a R C
Technology FusionTechnology Fusion
Carbon Nanotubes
I n f otechnology
B i otechnology N a n otechnology
Nanoelectronics
16N A S AN A S A L a R CL a R C
Role of Role of C N T sC N T s
– Enable radical design changes•Permit combination of properties
not previously possible•Affords multifunctionality for
increased efficiency
17N A S AN A S A L a R CL a R C
ChallengesChallenges
• Translating excellent combination of CNTproperties on the nanoscale to structuralproperties on the macroscale– Inconsistent quality of carbon nanotube
supply– Dispersion of carbon nanotubes– Characterization of carbon nanotube
nanocomposites– Scaling down processing equipment to
work around low CNT supply
18N A S AN A S A L a R CL a R C
Effect of CNTEffect of CNT Dispersability DispersabilityGood dispersion (optically dispersed)Poor pre-dispersion
0.05%SWNT-CP2Kinetically stable
After 2 years
0.05%SWNT-(b-CN)APB/ODPAThermodynamically stable
After 2 years
Direct mixing In situ polymerization under sonication
19N A S AN A S A L a R CL a R COunaies et al., Composites Sci. and Technol. ASAP (2003)
-18
-16
-14
-12
-10
-8
-6
-4
0 0.05 0.1 0.15 0.2
Transverse
Log 10
sDC
(S/cm
)
SWNT concentration (wt%)
r=0.7nm
r=2.1nm r=3.5nm
Dispersion EfficiencyDispersion Efficiency
-3 -2 -1 0 1 2 3 4 5 6 7-16
-14
-12
-10
-8
-6
-4
-2
20N A S AN A S A L a R CL a R C
UltemUltem & 1% SWCNTLaRC-8515LaRC- 8515 & 1% SWCNT
UltimateStrength
Yield Strength
0
50
100
150
200
MPa
Effect of CNT Reinforcement on Effect of CNT Reinforcement on Nanocomposite Nanocomposite Fiber StrengthFiber Strength
21N A S AN A S A L a R CL a R C
Fabrication of CNT Laminates andFabrication of CNT Laminates andC o mp o s ite sC o mp o s ite s
Laminate
Composite
22N A S AN A S A L a R CL a R C
Both NiCo and NiY Work in FELBoth NiCo and NiY Work in FELS y s t e mS y s t e m
• Unusual for both types of catalyst to work in same system
• Both show relatively small, randomly oriented bundles– Bundle diameter for NiY are 4 - 10 nm– Bundle diameter for NiCo are 4 - 18 nm
NiCo (0.5:0.5 at. %) catalystNiY (1:4 at. %) catalyst
23N A S AN A S A L a R CL a R C
TEM comparison, Nd:YAG (JSC) vs FELTEM comparison, Nd:YAG (JSC) vs FELSynthesized Raw MaterialSynthesized Raw Material
Nd:YAG laser FEL
24N A S AN A S A L a R CL a R C
HRTEM Shows Bundles,HRTEM Shows Bundles,Individual Tubes, & PeapodsIndividual Tubes, & Peapods
• No double-wall or multi-wall tubes were observed• Individual tubes and small bundles are seen• Fullerenic carbon shells are observed outside and inside the
nanotubes (peapods)
25N A S AN A S A L a R CL a R C
Raman Spectroscopy of FEL tubesRaman Spectroscopy of FEL tubesvs other Synthesis Techniquesvs other Synthesis Techniques
Spectra scaled for display purposed
0 500 1000 1500 20000
400
800
PLV (Ni)
HiPCo (Fe)
Arc (Ni-Y)
CVD (Fe-Mo)
FEL High Yield (Ni-Y),Toven~850 CI/2
Raman Shift (cm-1 )
Inte
nsi
ty (
arb
. un
its)
26N A S AN A S A L a R CL a R C
F E LF E L CNTs CNTs Enable NASA MissionsEnable NASA Missions
• World record production rate for laser synthesis– from mg/hr rates, to g/hr rates
• Analysis shows superior material - Control is key– higher purity– fewer defects– longer bundles of smaller diameter
• First material delivered to users– favorable properties for matrix reinforcement– good dispersion in films