Elastic deformation

Discussion in 'Homework Help' started by Hello, Jan 6, 2009.

  1. Hello

    Thread Starter Active Member

    Dec 18, 2008
    Describe how elastic deformation occurs in metal.

    I know that,
    Elastic deformation is nonpermanent, meaning that it is recoverable upon release of applied stress and that it is the deformation in which stress and strain are proprotional, but i am not sure how/if you have to relate it to metal?!

    Any help is appreciated.
  2. mik3

    Senior Member

    Feb 4, 2008
    Atoms in metals are tight together with electric forces. If you apply a tensile force on a metal the atoms start to move apart. If the force is strong enough, the atoms move more than the electric forces can hold and thus deformation is permanent. Otherwise the electric forces pull the atoms back.
  3. studiot

    AAC Fanatic!

    Nov 9, 2007
    I don't know where you are coming from on this one.

    All crystalline materials, metal and non metal, exhibit elasticity, with observed moduli in good agreement with predictions from atomic theory.

    However structure of the bulk material is different in metals, being made up of 'grains' which can be regarded as microcrystals all aligned at random orientations to each other.

    For metals, this gives bulk moduli and strengths much lower than the theoretical for single crystals. These moduli are commonly known as 'engineering moduli ' and are controlled largely by the theory of defects within the grain structure. This is a huge theory.

    For non metals the modulus is closer to theoretical maximum as the crystals deform until they break, usually in a brittle manner.