Mechanical Properties Of Solids

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The mechanical properties of a material are those properties that involve a reaction to an applied load. The mechanical properties of metal determine the range of usefulness of a material and establish the service life that can be expected. Mechanical properties also used to help classify and identify material. The most common properties considered are:

  • Strength


The general ability of a material to withstand an applied force.

  • Hardness


Hardness is a measure of how easily a material can be scratched or indented. Hard materials are often also very brittle – this means they have a low resistance to impact. Well Known hard materials include diamond and hardened high carbon steels.

  • Brittleness


A material that has tendency to break easily or suddenly without any extension first. Good examples are Cast iron, Concrete, High carbon steels, Ceramics, and some polymers such as Urea formaldehyde (UF).

  • Toughness


A material that absorbs impact (sudden forces or shocks such as hammer blows) well is tough – this is opposite to the brittleness. [units for toughness are energy per unit area – J/

  • Plasticity


The materials which deform permanently when small forces are applied show plasticity. Plasticine and clay are good examples.

  • Elasticity


The ability of a material to return to its original form after a load has been applied and removed. Good examples include Rubber, Mild steel, and some plastics such as Nylon.

  • Stiffness



The ability to resist bending is known as the stiffness.

  • Ductility


The ability to be drawn out into a thin wire or threads. It is a measure of how easily a material can be worked .Good examples are Gold, Copper, Titanium, Wrought iron, Low carbon steels and brass. It also provides an indication of how visible overload damage to a component might become before the component fractures. It is also used as a quality control measure to assess the level of impurities and proper processing of a material.


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