Download Auxetic Materials (Zahra Elkassabgi)

Auxetic Materials
by:
Zahra Elkassabgi
What’s Poisson Ratio?

Ratio of axial and lateral strains

Formulated so most materials with positive value

ν= -Єx = -Єy
Єz
Єz
What are auxetic materials and
their properties?

Materials with a negative Poisson Value

Density may vary from one-trillionth the density
of air or 100 billion times air

Formed -460*F or 10,000+ heat of white dwarf
stars
Auxetic v. Normal materials



Auxetic materials

Normal materials

Smaller when stretched

Larger when compressed
Larger when stretched
Smaller when
compressed
Applications of Auxetic materials

Nature
Manufactured
(still under research)


Neutron stars

Artificial muscles

White dwarf

Artificial arteries

Skin of a cat

Structural connectors
Advantages of auxetic materials

Increased shear stiffness

Increased plane strain fracture toughness

Increased indentation resistance

Superior to conventional materials for many
practical applications
References

http://www.dallasnews.com/sharedconntent/dallas/healthscienc
es/stories

http://silver.neep.wisc.edu/~lakes/PoissonStru.html

http://silver.neep.wisc.edu/~lakes/PoissonEnd.html

http://silver.neep.wisc.edu/~lakes/Poisson.html
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