Multifunctional Materials and Structures

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Multifunctional Materials and Structures

• Dimitris C. Lagoudas
• Director of the Texas Institute for Intelligent
  Bio-Nano
• Materials and Structures for Aerospace Vehicles
• Department of Aerospace Engineering
• Texas AM University

The Academy of Medicine, Engineering and Science
of Texas 2005 Conference

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Goals for Future Aerospace Systems
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TiiMS University Participants
A University Research, Engineering and Technology
Institute has been established to address
interdisciplinary research for multifunctional
bio-nano materials and structures.
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TiiMS Kickoff Meeting October 2002
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Texas Institute for Intelligent Bio-Nano
Materialsand Structures for Aerospace Vehicles
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Chief Engineer and Chief Scientist
Dr. Richard Smalley Co-principal Investigator
and Former Chief Scientist
Dr. John Junkins Chief Engineer
Dr. James M. Tour Chief Scientist
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Examples of TiiMS University Collaborations
UTA TAMU Fabrication of MEMS thermoelectric
devices.
Rice TAMU High shear mixing of CNTs in polymers.
UH TAMU PVAMU Adaptive wing demonstration.
UH Rice TAMU Fabrication and characterization
of nanocomposites.
Rice PVAMU Irradiation studies of CNTs and CNT
composites.
TSU - Rice Bio-applications of nanocomposites.
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TiiMS Education and Outreach
Number of Students Supported by TiiMS 19
Post-doctoral Researchers 70 Graduate Students 36
Undergraduate Students
Materials Magic to teach K-12 Nanotechnology
Research Experience for Teachers Summer 2003
Final Research Presentations
Teacher Training Workshops
Field Trip to NASA JSC
NanoKids Project
Research Experience for Undergraduates Summer 2003
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Impact on K-12 Education
Jim Tours NanoKids curriculum is currently used
in Texas middle and high school classrooms.
Rick (Fred Flintstone) Barrera and Fernando
(The Chemist) Rodriguez perform for hearing
impaired children at T. H. Rogers Elementary
School.
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Multifunctional Material Systems

• Research Activities
• Multifunctional materials and structures at nano
  micro meso - macro physical length scales.
• Hierarchical material models for structural,
  electrical, magnetic and thermal functionalities.
• Integration of multifunctional materials into
  intelligent aerospace structures.

Turbulent Drag Reducing Epidermis with Embedded
Nanotube Skin Friction Sensors
MEMS Piezoceramic Actuators for Epidermis Shape
Control
Supercapacitor for Powering the Piezoceramic
Actuators
Collapsible Cellular Structure with NiTi cells,
using Pseudoelasticity Effect for Impact
Absorption
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Actuation Characteristics of Multifunctional
Materials
Courtesy of Prof. Don Leo, VPI
Shape Memory Alloys (SMAs)
Electroactive Ceramics
I-PVDF
Carbon Nanotubes
Ionic / Electronic Conducting Polymers
Dielectric Elastomer
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Hierarchical Modeling of Multifunctional
Materials Scale Transitions
Quantum Mechanics/Newtonian Mechanics Carbon
Nanotube Properties
Example Mode 1 ? 514.9 cm-1

• Atomistic/Continuum Modeling
• Carbon Nanotube Properties
• Interaction CNT w/Polymer

• Continuum Modeling Micromechanics
• Effective CNT Properties
• Effective Composite Properties for
  CNT/Polymer Composites

Effective Composite
SWCNT
SWCNT/Polymer
Eff. SWCNT
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Integration of Multifunctional Materials into
Aerospace Structures
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Current Applications of Multifunctional
Materials SMAs
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Shape Memory Alloys (SMAs) Coupled
thermo-mechanical constitutive response
Plastic Deformation
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1
2
Detwinned Martensite
? 1
? 0
2
Austenite
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Twinned Martensite
3
?
?
?
?
?
?
?
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Modeling of Multifunctional Structures
Constitutive response must be integrated with the
structure and environmental inputs
SMA Flow Regulator
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Coupled fields essential in multifunctional
materials Magnetic SMAs (MSMAs)

• Experimental Characterization of MSMAs under
  variable mechanical load, thermal load, and
  applied magnetic field.
• Various material systems are being tested
• NiMnGa, CoNiAl, CoNiGa

In Cooperation with Dr. I. Karaman, Department of
Mechanical Engineering, Texas AM University.
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Modeling of constitutive response of
multifunctional materials must account for
nonlinear phenomena due to couplings
Magneto-mechanical modeling of MSMAs
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The Future of Multifunctional Materials
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Research Challenge Bridging the Length
Scales From Nanomaterials to Aerospace Systems
10-10m

102m
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Acknowledgement to Dedicated Graduate Students

• http//tiims.tamu.edu
• http//smart.tamu.edu

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Thank you!
Ich danke Ihnen
Sa? e??a??st?
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Le agradezco
Ik dank u
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Li ringrazio
Eu agradeço-o