MSD: Exploiting Material Anisotropy in Design

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MSD Exploiting Material Anisotropy in Design

• Joshua R. Houskamp
• Surya R. Kalidindi
• Funding by D. Stepp (ARO)

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Complete Product Design

• Product
• Component
• Microstructure
• Nanostructures

NASA
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Current Design Method

• Typically Materials Selection and Geometry
  Optimization
• Materials thoroughly characterized to meet
  material specifications
• Geometry Optimization through FEM

Database Materials Selection
Iterative design
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Anisotropy
Optical properties
Mechanical properties
Magnetic properties
Experimentally measured anisotropy magnetic
fields from nanomagnets
Source  D.K. Koltsov
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Novel Methods of Engineering Design

• Topology Optimization
• Spatial arrangement of materials with different
  (isotropic) properties with void space
• a, k, snap-fit connectors, injection molding
  platens
• Torquato(1997), Sigmund (1994, 1997)
• Systems approach Materials by Design
• collection of forward problems linked empirically
• Steel, aluminum, shape memory alloys
• Olsen (1997,2000), QuesTek
• Drawbacks
• Not rigorously bounded design space
• Non-convex design space
• Non-unique solutions
• No Consideration of anisotropy at the local state

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Fundamental Problems in Materials Design

• Can we identify the complete set of
  microstructures that are predicted to yield a
  specific combination of properties?
• Can we identify processing routes to achieve the
  identified microstructures?

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Problem Statement

• Made with a continuously reinforced fibrous
  composite
• What is the best fiber orientation distribution
  to maximize load carrying capacity?

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Microstructure Representation
Symmetry Requirements
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Microstructure Hull Composites
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Two Level Homogenization Composites

• Meso-scale Homogenization scheme
• Single Lamina
• Rule of mixtures type homogenization

• Macroscale Homogenization
• Weighted Volume average
• of individual plys

Subject to
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Property Closures Composites
a 0.5
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Circular hole in a plate

• Potential factor of improvement of up 4
• Conservatively, based on (WAM) property
  estimates, design is improved by a factor of 2

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Extension to Polycrystalline Metals

• Consider polycrystalline metals 3D Composites
• Consequently

Bunge, H.-J., Texture analysis in materials
science. Mathematical Methods. 1993, Göttingen
Cuvillier Verlag.
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Results
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Conclusions

• Case study shows an enriched design space when
  local anisotropy considered
• MSD identifies a class of microstructures that
  provide a similar performance metric
• Accuracy of solutions is dependant on truncation
  of Fourier series
• MSD may be readily applied several classes of
  materials with differing symmetries

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Current Standings

• Ph.D. Completion Summer of 2005
• Currently interviewing for Post Doctoral
  positions at Army Research Labs, Aberdeen, MD