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Metal stretching, heat and hysteresis

  1. Apr 22, 2013 #1
    Stretch piece of metal within its elastic limit and it cools down.
    Does it cool down for the same reason that a gas cools down when expanded?

    But if the piece of metal is repeatedly stretched and released (like with a spring), I am led to believe that it heats up, although I am not sure.
    I know that the process of cycling the metal within its elastic limit is not 100% efficient, and this is due to hysteresis. So whether repeatedly stretched or compressed, I would expect the metal will heat up.
    Last edited: Apr 22, 2013
  2. jcsd
  3. Apr 22, 2013 #2
    Right track

    When you stretch a spring it will cool down a small amount like you think for a fairly similar reason as a gas, essentially boiling down to a constant amount of energy existing in a larger space.

    you are also correct that the model you described above is a "perfect" model. Although this is often assumed to be 100% efficient for metals, this is never true and some heat is generated.
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