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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

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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

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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

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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

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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

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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

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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

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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

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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

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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

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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

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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

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• 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

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Technology FusionTechnology Fusion

Carbon Nanotubes

I n f otechnology

B i otechnology N a n otechnology

Nanoelectronics

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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

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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

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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

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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

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Fabrication of CNT Laminates andFabrication of CNT Laminates andC o mp o s ite sC o mp o s ite s

Laminate

Composite

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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

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TEM comparison, Nd:YAG (JSC) vs FELTEM comparison, Nd:YAG (JSC) vs FELSynthesized Raw MaterialSynthesized Raw Material

Nd:YAG laser FEL

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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)

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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)

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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