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Applications
MAE 438/538
Smart Materials
Professor Deborah Chung
[email protected]
Furnas Hall, Room 608
Tel. (716) 645-2593 X2243
Fax. (716) 645-3875
Grading scheme for
MAE 438
Test 1
Test 2
Final
25%
25%
50%
Grading scheme for
MAE 538
Test 1
Test 2
Final
Paper
20%
20%
40%
20%
Test dates
Test 1: Feb. 3, 2005
Test 2: Mar. 22, 2005
Smart materials
Materials for
smart structures
Smart structures
Structures that can
sense stimuli and
respond to them in
appropriate fashions
Civil structures
Buildings
Bridges
Piers
Highways
Airport runways
Landfill cover
Lightweight structures
 Aircraft
 Satellites
 Turbine blades
 Automobiles
 Bicycles
 Sporting goods
 Wheelchairs
 Transportable bridges
•
•
•
•
•
Functions for
structures
Structural
Vibration reduction
Self-sensing of strain/stress
Self-sensing of damage
Electromagnetic interference (EMI)
shielding
• Lightning protection
• Self-heating (e.g., deicing)
• Self-healing
Applications of
strain-stress sensing
• Traffic monitoring
• Weighing (including weighing
in motion)
• Building facility management
• Security
• Structural vibration control
Applications of
damage sensing
• Structural health
monitoring
• Damage/microstructural
evolution study
Damage sensing
methods
• Acoutic emission
• Electrical resistivity
measurement
• Optical fiber sensor
embedment
Piezoresistivity
• Change of electrical resistivity due
to strain
• Gage factor = fractional change in
resistance per unit strain
(more than 2)
• Gage factor up to 700 attained in
carbon fiber reinforced cement
Self-healing concept
• Embedding microcapsules of monomer in
composite
• Having catalyst in composite outside the
microcapsules
• Upon fracture of microcapsule, monomer
meets catalyst, thereby former a polymer
which fills the crack.
Problems with
self-healing
• Toxicity of monomer
• High cost of catalyst
Types of smartness
•Extrinsic smartness
•Intrinsic smartness
Advantages of
intrinsic smartness
•
•
•
•
Low cost
High durability
Large functional volume
Absence of mechanical
property loss
Advantages of
automatic highway
Safety
Mobility
Lane
Lane
(a)
(b)
Applications of materials
Topic 1
Reading assignment
Chung, “Composite Materials”,
Ch. 1 on Applications.
Askeland and Phule, The Science
and Engineering of Materials, 4th
Edition, Ch. 15 on Polymers.
Applications
Structural applications
Electronic applications
Thermal applications
Electrochemical applications
Environmental applications
Biomedical applications
History of human
civilization
Stone Age
Bronze Age
Iron Age
Steel Age
Space Age
Electronic Age
Types of materials
Metals
Ceramics
Polymers
Semiconductors
Composite materials
Ceramics
Ionic/covalent bonding
Very hard (brittle)
High melting temperature
Low electrical/thermal
conductivity
Examples of ceramics
Al2O3 (aluminum oxide or
alumina)
Fe3O4 (iron oxide or ferrite)
WC (tungsten carbide)
Cement (silicates)
Polymers
Molecules
Soft
Low melting temperature
Low electrical/thermal
conductivity
(PVC)
©2003 Brooks/Cole, a division of Thomson Learning, Inc. Thomson Learning™ is a trademark used herein under license.
©2003 Brooks/Cole, a division of Thomson Learning, Inc. Thomson Learning™ is a trademark used herein under license.
Styrene
Examples of polymers
Rubber
Polyester
Nylon
Cellulose
Pitch
Copolymer
Polymer
blend
©2003 Brooks/Cole, a division of Thomson Learning, Inc. Thomson Learning™ is a trademark used herein under license.
©2003 Brooks/Cole, a division of Thomson Learning, Inc. Thomson Learning™ is a trademark used herein under license.
Styrene-butadiene block copolymer
Branching
©2003 Brooks/Cole, a division of Thomson Learning, Inc. Thomson Learning™ is a trademark used herein under license.
Types of polymer
Thermoplastic (softens upon
heating)
Thermoset (does not soften
upon heating)
Compression molding
Composites
Artificial combinations of
materials
Composite materials
Polymer-matrix composites
Cement-matrix composites
Metal-matrix composites
Carbon-matrix composites
Ceramic-matrix composites
Composite materials
Particulate
Fibrous (discontinuous fibers)
Fibrous (continuous fibers)
Lamellar
Cement-matrix composites
Cement paste
Mortar
Concrete
Carbons
 Graphite
 Diamond
 Fullerenes (buckminsterfullerenes)
 Carbon nanotubes
 Turbostratic carbon
 Diamond-like carbon (DLC)
 Intercalation compounds of graphite
 Exfoliated graphite (“worms”)
 Flexible graphite
Structures
 Buildings, bridges, piers, highways,
landfill cover
 Aircraft, satellites, missiles
 Automobiles (body, bumper, shaft,
window, engine components, brake, etc.)
 Bicycles, wheelchairs
 Ships, submarines
 Machinery
 Tennis rackets, fishing rods, skis
Structures (continued)
 Pressure vessels, cargo containers
 Furniture
 Pipelines, utility poles
 Armor, helmets
 Utensils
 Fasteners
 Repair materials
Multifunctionality in structures
 Load bearing
 Assembly and packaging
 Vibration reduction (damping)
 Structural health monitoring
(damage sensing)
 Structural vibration control
 Modulus control
Multifunctionality in
structures (continued)

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


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


Self-sensing of strain, damage and temperature
Building management
Building security
Thermal insulation
Self-heating (e.g., deicing)
Self-healing
Electromagnetic interference (EMI) shielding
Low observability (Stealth)
Energy generation
Embedded or attached
devices or materials
 Sensors (e.g., , strain gages, optical
fibers)
 Actuators (e.g., electrostrictive
materials, magnetostrictive materials,
shape-memory alloys, etc.)
 Viscoelastic materials
 Magnetorheological materials
 Electrorheological materials
Disadvantages of embedded
or attached devices
High cost
Poor durability
Poor repairability
Limited functional volume
Degradation of mechanical
properties
Structural performance
 High strength
 High modulus (stiffness)
 Mechanical fatigue resistance
 Thermal fatigue resistance
 Low density
 Corrosion resistance
 Moisture resistance
 Freeze-thaw durability
Structural performance
(continued)
 High temperature resistance
 Thermal shock resistance
 Low thermal expansion coefficient
 Creep resistance
 Low fluid permeability
 Repairability
 Maintainability
 Processability
Electronic applications
Electrical applications
Optical applications
Magnetic applications
Electrical applications
 Computers
 Electronics
 Electrical circuitry (resistors, capacitors,
inductors)
 Electronic devices (diodes, transistors)
 Optoelectronic devices (solar cells, light
sensors, light-emitting diodes)
 Thermoelectric devices (heaters, coolers,
thermocouples)
Electrical applications
(continued)
 Piezoelectric devices (sensors, actuators)
 Robotics
 Micromachines (microelectromechanical systems
or MEMS)
 Ferroelectric computer memories
 Electrical interconnections (solder joints, thickfilm conductors, thin-film conductors)
 Dielectrics (electrical insulators in bulk, thickfilm and thin-film forms)
Electrical applications
(continued)
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
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Substrates for thin films and thick films
Heat sinks
Electromagnetic interference (EMI) shielding
Cables
Connectors
Power supplies
Electrical energy storage
Motors
Electrical contacts, brushes (sliding contacts)
Electrical applications
(continued)
Electrical power transmission
Eddy current inspection (use of a
magnetically induced electrical
current to indicate flaws in a
material)
Optical applications
 Lasers
 Light sources
 Optical fibers (materials of low optical absorptivity for
communication and sensing)
 Absorbers, reflectors and transmittors of
electromagnetic radiation
 Photography
 Photocopying
 Optical data storage
 Holography
Magnetic applications
 Transformers
 Magnetic recording (data storage)
 Magnetic computer memories
 Magnetic field sensors
 Magnetic shielding
 Magnetically levitated trains
Magnetic applications
(continued)
 Robotics
 Micromachines
 Magnetic particle inspection
 Magnetic energy storage
 Magnetostriction
 Magnetorheological fluids
 Magnetic resonance imaging (MRI, for
patient diagnosis)
 Mass spectrometry (for chemical analysis)
Electronic packaging
 Electrical interconnections
 Chip carriers
 Interlayer dielectrics
 Encapsulations
 Heat sinks
 Thermal interface materials
 Housings
 EMI shielding
Thermal applications
 Heating and cooling of buildings
 Industrial heating (casting, annealing,
deicing, etc.)
 Refrigeration
 Microelectronic cooling
 Heat removal (brakes, cutting,
welding, chemical reactions, etc.)
Mechanisms of heat
transfer
 Conduction (by electrons, ions or
phonons)
 Convection (by hot fluid, whether forced
or natural convection)
 Radiation (black-body radiation,
particularly infrared radiation, for space
heaters)
Materials for thermal
applications
Thermal conductors
Thermal insulators
Heat retention materials (high
heat capacity)
Thermal interface materials
Thermoelectric materials
Electrochemical
reaction
Anode
Cathode
Electrolyte
Catalyst (optional)
Electrochemical
applications
Batteries
Fuel cells (galvanic cells in which
the reactants are continuously
supplied, e.g., the hydrogenoxygen fuel cell)
Environmental
protection
 Pollutant removal (e.g., filtration,
absorption by activated carbon)
 Reduction in the amount of pollutant
generated (e.g., use of biodegradable
polymers)
 Recycling
 Electronic pollution control
Biomedical applications
Diagnosis
Treatment
Scope: conditions, diseases,
disabilities, and their prevention
Biomedical materials and
devices
 Implants
 Bone replacement materials
 Bone growth support
 Surgical and diagnostic devices
 Pacemaker
 Electrodes for collecting or sending
electrical or optical signals
Biomedical materials and
devices (continued)
Wheelchairs
Devices for helping the disabled
Exercise equipment
Pharmaceutical packaging
Instrumentation
Requirements of implant
materials
Biocompatible
Corrosion resistant
Wear resistant
Fatigue resistant
Durability for tens of years
A biomedical composite
material
Particulate composite
Ceramic particles:
hydroxyapatite + tricalcium
phosphate
Polymer matrix: collagen
Desirable qualities of an
adsorption material
 Large adsorption capacity
 Pores accessible from the outside
 Pore size large enough for relatively large
molecules or ions to lodge
 Ability to be regenerated or cleaned after use
 Fluid dynamics for fast movement of the fluid
 Selective adsorption of certain species
Pore size nomenclature
 Macropores (exceeds 500 Å)
 Mesopores (between 20 and 500 Å)
 Micropores (between 8 and 20 Å)
 Micromicropores (less than 8 Å)
Functions of filter
materials
Molecule or ion removal
(by adsorption)
Particle removal
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