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EF 152EF 152Materials RecitationMaterials Recitation
August 31, 2009August 31, 2009
Materials Science and EngineeringMaterials Science and EngineeringDepartmentDepartment
22
Materials RecitationMaterials Recitation
Space Elevator Material RequirementsSpace Elevator Material Requirements
Hot Wire & Shape Memory DemoHot Wire & Shape Memory Demo
Material ApplicationsMaterial Applications Heat SinkHeat Sink Biomimetic Biomimetic LensLens SpaceShipOneSpaceShipOne
Affect of Heat Treatment DemoAffect of Heat Treatment Demo
MSE Dept. InformationMSE Dept. Information
33
Space ElevatorSpace Elevator
44
LifterLifter
55
Space ElevatorSpace Elevator
rocket: $20,000/kg to orbitrocket: $20,000/kg to orbitelevator: $200/kg to orbitelevator: $200/kg to orbitelevator much saferelevator much safer no rocketsno rockets no re-entry heatno re-entry heat
~$10 billion to build elevator~$10 billion to build elevator NASA budget = $15 billion/yrNASA budget = $15 billion/yr $0.5 billion per shuttle launch$0.5 billion per shuttle launch
8 days one way8 days one way
material for cable?material for cable?
66
Material requirements forcable?
strength
density
77
Geostationary OrbitGeostationary Orbit
=!
hrsec
dayhr 600,324
2 R"
Fg
v
R
( )
m 42.24x10
360024
4
6
22
2
2
2
gravity
=
=!
=
=
R
R
mmG
Rm
R
mmG
R
mv
Fma
E
E
n
"
Geostationary: satellitestays above same point onearth’s surface(geosynchronous)
88
Force on CableForce on Cable
Cable must support weight of cable beneath itCable must support weight of cable beneath it
dRR
GMrdF cableg 2
2!"=
[ ]112
R
6456
2
2
)m645.6()kg 246)(1167.6(
1)(
2
3 !! !!=
= "
REEEr
dRR
GMrRF
skg
m
E.
cable
g
#$
#$
!"
#
"!
2
2
2
2
7E3.5
7E3.5
m, 42.24E6 Rat
2
2
s
m
cable
gcable
s
mcable
g
r
F
rF
==
=
=
99
Material Requirement for CableMaterial Requirement for Cable
32
2
kg/m
Pa
s
m 73.5735 EE.ñ
óUTS
==
“Specific Strength”
1010
StrengthStrength
1111
DensityDensity
1212
Specific StrengthSpecific Strength
Material _ (kg/m3) _UTS (MPa) _UTS/_ (m2/s
2)
7075 T6 Al 2,800 505 1.8E+05
Ti-6Al-4V 4,430 1,172 2.6E+05
440A Stainless steel 7,800 1,790 2.3E+05
Nylon 6,6 1,140 90 7.9E+04
Polyester 1,250 85 6.8E+04
Kevlar 49 1,440 4,100 2.8E+06
Spectra 2000 970 3,340 3.4E+06
Silicon Carbide 3,200 825 2.6E+05
Silicon Nitride 3,300 1,000 3.0E+05
Diamond 3,400 1,400 4.1E+05
C fiber 1,790 6,350 3.5E+06
E-glass 2,580 3,450 1.3E+06
1313
Specific StrengthSpecific Strength
σ UTS/ρ
= 5.3E
7 m2 /s
2
1414
Carbon Carbon NanotubesNanotubes
11stst produced in 1991 produced in 1991C=C double bonds C=C double bonds stronger than diamond stronger than diamond~ 1 nm in diameter~ 1 nm in diameter
1515
Carbon Carbon NanotubesNanotubes
100 X stronger than diamond100 X stronger than diamond1/6 density of steel1/6 density of steelup to 500 X specific strength of steelup to 500 X specific strength of steelρρ = 1,300 kg/m= 1,300 kg/m33
highest measured strength = 63 highest measured strength = 63 GPaGPa 4.8E7 m 4.8E7 m22/s/s22 90% of target90% of targettheoretical strength = 150 theoretical strength = 150 GPaGPa 11.4E7 m 11.4E7 m22/s/s22
suitable for space elevator cablesuitable for space elevator cable
1616
Carbon Carbon Nanotubes Nanotubes ChallengesChallenges
CNTs CNTs are 4 cm long, 1 nm diameterare 4 cm long, 1 nm diameterneed 36,000 km long, 0.5 mm diameter cableneed 36,000 km long, 0.5 mm diameter cable composites containing 50% composites containing 50% CNTsCNTs
binding between binding between CNTs CNTs and matrixand matrixkm long composite fibers (3% CNT) have beenkm long composite fibers (3% CNT) have beenproduced with 2 produced with 2 GPa GPa strengthstrength
twisted CNT yarntwisted CNT yarnCost, ~ $25,000 per kgCost, ~ $25,000 per kg
1717
Hot Wire & Shape MemoryHot Wire & Shape MemoryDemonstrationsDemonstrations
1818
Thermal ManagementThermal Management
Heat generated by electronic devices must beHeat generated by electronic devices must bedissipated to improve reliability and prevent failure.dissipated to improve reliability and prevent failure.
1919
Thermal ManagementThermal Management
Heat Sink DesignHeat Sink Design
2020
Thermal ManagementThermal Management
Which has highest thermal conductivity?Which has highest thermal conductivity?
AluminumAluminum
DiamondDiamond
GoldGold
SilverSilver
2121
Thermal ManagementThermal Management
2222
Chemical Vapor Deposition (CVD)Chemical Vapor Deposition (CVD)
methane (CH4) is heated: CHmethane (CH4) is heated: CH44 C + 4H C + 4Hgaseous C can deposit on substrate as diamondgaseous C can deposit on substrate as diamond
Synthetic DiamondSynthetic Diamond
2323
ProblemsProblems
Difficult to produce large areas (cmDifficult to produce large areas (cm22))
Slow growth ratesSlow growth rates
CostCost
Synthetic DiamondSynthetic Diamond
2424
Lenses in NatureLenses in Nature
Hierarchical layered protein structuresHierarchical layered protein structures
Refractive index gradientsRefractive index gradients Enhance focusing powerEnhance focusing power
Correct aberrationsCorrect aberrations
Reduce number of components neededReduce number of components neededfor optical systemfor optical system
2525
Traditional LensTraditional Lens
Focus is a result of geometry and refractionFocus is a result of geometry and refractionRefractive index does not vary within lensRefractive index does not vary within lens
2626
Focusing by an index gradient aloneFocusing by an index gradient alone
2727
Multilayer Polymer Gradient Index (GRIN) LensMultilayer Polymer Gradient Index (GRIN) Lens(Case Western Reserve University*)(Case Western Reserve University*)
* funded by DARPA 2828
Multilayer FilmsMultilayer Films
10 10 splittings splittings 2048 layers 2048 layers50 50 µµm m film film 24 nm layers (must be < 50 nm for transmission) 24 nm layers (must be < 50 nm for transmission)Polycarbonate (PC), n = 1.58Polycarbonate (PC), n = 1.58 CD, DVD substrates, eyeglasses, water bottlesCD, DVD substrates, eyeglasses, water bottles
Poly(methyl Poly(methyl methacrylatemethacrylate) (PMMA), n = 1.49) (PMMA), n = 1.49 PlexiglassPlexiglass, latex paint, countertops, lenses, aircraft cockpits, latex paint, countertops, lenses, aircraft cockpits
2929
Multilayer FilmsMultilayer Films
Refractive index of film corresponds to a thickness-weightedRefractive index of film corresponds to a thickness-weightedaverage of the indices of the component polymersaverage of the indices of the component polymers
3030
GRIN FilmGRIN Film
...
...
100/0 PMMA/PC, n = 1.490
0/100 PMMA/PC, n = 1.580
99/1 PMMA/PC, n = 1.491
98/2 PMMA/PC, n = 1.492
50/50 PMMA/PC, n = 1.535
2/98 PMMA/PC, n = 1.578
1/99 PMMA/PC, n = 1.579
3131
GRIN Lens FabricationGRIN Lens Fabrication
3232
X-PrizeX-Prize
US $10M prize for the first non-government organization tolaunch a reusable manned spacecraft into space twice withintwo weeksSpaceShipOneSpaceShipOne, October 2004, October 2004
3333
X-PrizeX-Prize
3434
SpaceShipOne
produced by Scaled Composites, LLC.designed by Burt Rutanproject funded at $20M by Paul Allen (Microsoft)carried to 14 km by White Knight aircraft(afterburning twin turbojets)hybrid rocket motor generates 88 kN thrust for 87sec.reached altitude of112 kmnow on display at National Air and Space Museum
3535
WhiteKnightOne and SpaceShipOneWhiteKnightOne and SpaceShipOne
3636
SpaceShipTwo
produced by Scaled Composites & Virgin (RichardBranson)2X size of SpaceShipOneprivate spaceflight service starting 2009 or 2010two pilots and six passengers110 km target altitudecarried to 15 km by White Knight Two$200,000 per flight200 customers have pre-paidpassengers must pass 6-8 g centifruge test
3737
MaterialsCarbon fiber composites have excellent strength toweight ratio (specific strength)Glass and Kevlar fibers also usedHigh performance, toughened epoxy matrixCarbon fiber panels sandwiched around honeycombcoreWhite Knight Two largest all-carbon-fiber aircraft ever built 140 ft wing spar is the longest single carbon
composite aviation component ever manufactured most fuel efficient airplane ever created
3838
Affect of HeatAffect of HeatTreatmentTreatment
BrassBrassTool SteelTool Steel
3939
Materials Science & EngineeringMaterials Science & Engineering
Structure
Processing PropertiesEngineering
Science Scienc
e
MATERIALS DEVELOPMENT4040
MSE at UTMSE at UT
Class Size ~ 10-15 per yearClass Size ~ 10-15 per yearScholarships, ~ 75% receivingScholarships, ~ 75% receivingscholarships from dept: $800 - $2600scholarships from dept: $800 - $2600per yearper year28 Faculty28 Faculty~ $5 M in annual research funding~ $5 M in annual research fundingUG research, thesis or paidUG research, thesis or paid
4141
MSE ScholarshipsMSE Scholarships
FreshmanFreshman $800 - $1,200 per year$800 - $1,200 per year
SophomoreSophomore $1,200 - $1,600 per year$1,200 - $1,600 per year
JuniorJunior $1,600 - $2,100 per year$1,600 - $2,100 per year
SeniorSenior $2,100 - $2,600 per year$2,100 - $2,600 per year
4242
MSE CurriculumMSE Curriculum
FundamentalsFundamentals
ThermodynamicsThermodynamicsKinetics & Transport PhenomenaKinetics & Transport PhenomenaProcessingProcessingMechanical BehaviorMechanical BehaviorDiffusion & Phase TransformationsDiffusion & Phase TransformationsStructural CharacterizationStructural CharacterizationMaterials Lab (2 semesters)Materials Lab (2 semesters)
4343
MSE CurriculumMSE Curriculum
Material ClassesMaterial Classes
PolymersPolymersCeramicsCeramicsMetal AlloysMetal AlloysElectrical & Optical MaterialsElectrical & Optical Materials
4444
MSE CurriculumMSE Curriculum
DesignDesign
Materials SelectionMaterials SelectionMaterials DesignMaterials Design
ElectivesElectives
Electronic DevicesElectronic DevicesPolymer ProcessingPolymer ProcessingBiomaterialsBiomaterialsPolymer EngineeringPolymer Engineering
Cell & Tissue-Cell & Tissue-Biomaterials InteractionBiomaterials InteractionIntermetallics & CompositesIntermetallics & CompositesAdvanced BiomaterialsAdvanced Biomaterials
4545
Biomaterials ConcentrationBiomaterials Concentration
4 required courses4 required courses
2 MSE 4XX Electives2 MSE 4XX Electives
2 Technical Electives2 Technical Electives
Nanomaterials Concentration planned forNanomaterials Concentration planned for2010-2011 Catalog2010-2011 Catalog
4646
Research OpportunitiesResearch Opportunities
• ~ $5 M in annual research funding• Subsidized research opportunities for freshmen &
sophomores• Several research opportunities at ORNL• Recent undergraduate research topics include
Piezoelectric Polymer Fibers Computer Modeling of Micro-Scale Grains Infrared Dichroism of Nonwoven Polymer Fibers Nanocrystalline Biosynthesized Magnetite Retained Austenite in Magnetically Processed Steel Processing of Graphite Carbon Foams
4747
For more information, contact:For more information, contact:Dr. Kevin KitDr. Kevin [email protected]@utk.edu510 Dougherty510 Dougherty974-7055974-7055