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Smart Materials

  1. Dec 23, 2012 #1
    Is there any material which could change from liquid state to solid state after appiled some force?

  2. jcsd
  3. Dec 23, 2012 #2


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    Some non-newtonian fluids can do something similar - they will return to the fluid state if the force stops, however.
  4. Dec 24, 2012 #3
    a shear thickening fluid (approximately) may serve your purpose. Its viscosity increases considerably when stressed. Best example is a wheat flour dough. Initially it has low viscosity but as you start applying force to make is uniform it becomes more viscous.
    Density wise I cant think of an example (density increasing considerably with applied stress) in semi solid and solid materials.
  5. Dec 24, 2012 #4
    In fact corn starch suspension is a very good shear thickening liquid (much better than wheat though), for example you can run over it, but if you walk slowly you will sink: see demo here.
  6. Dec 24, 2012 #5
    Thank you Very Much Mr.Alkim,Mr.pukb,Mr.mfb. :shy:
    Now I got an idea, how to make it........... really super video alkim. another thing I want to know that, Is this fluid acts as a Bullet proof?. I mean it will withstand the deformation of the pointed bullet penetration.
    And too this one if the penetration made by the projectile will heals itself? Like self Haling Structure......

    Actually my target is 18mm thickness, I just want to make the target into low penetration material. is that possible by making layer of metal and Non Newtonian fluid to avoid penetration? if I'm using RHA is a target means 3 layers of RHA with 3mm thickness and 3 layers of Non Newtonian fluid with 3mm thickness. the arrangement is like layer by layer, first RHA, then Non Newtonian. this one is my need? is that possible?
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