IMPORTANT MECHANICAL PROPERTIES.

Follwing some importan mechanical properties.

1. Strength: The capacity of material to withstand load is called strength.The strength of material is its ability to sustain loads without rupture or collapse.The maximum stress that any material can withstand is called ultimate strength ortenacity.
2. Elasticity: On a material,when external load is applied it undergoes deformation and on removal of the load if returns to its origanal shape, this property of material is called elasticity.Such a material is called elastic material.
3. Plasticity: If a material does not regain its origanal shape ,on removal of the external load,it is called plastic material.Plasticity is the property of a material by virtue of which material can be moulded in to desire shape. It is the lack of elasticity.
4. Ductility: If a material undergo a considerable deformation ,without rupture it is called a ductile material and this property of material  is called ductility.Most ductile material is steel and grey castiron is least ductile material.As temperature increases,ductility increases.
5. Brittleness:If material can notundrgo any deformation,when some external forces act on it and it fails by rupture,it is called a brittle material.Brittle materials are stronger in compression and weak in tension.Materials having less than 5% elongation are considered as brittle.
6. Malleability:It is property of a material by virtue of which material can be converted in to thin sheets by hammering.Malleable material can be easily rolled and forged without cracking or breaking.Gold is the most malleable material while cast iron is the least malleable material.This is also a compressive quality of a material.
7. Toughness:Capacity of a material to absorb energy before rupture is called toughness.
8. Hardness:Resistance of a material to abrasion,wear and scratches is called hardness.An alloyed cast iron is the hardest material while magnesium alloy is the softest material.
9. Stiffness:Resistance to deformation or strain is called stiffness.Force required to produce unit deformation in a material is called stiffness.Steel is considered as a stiffer material.
10. Endurance: The capacity of a material to withstand repeated stress cycles is known as Endurance of a material.
11. Fatigue strength:The maximum sress,which a material can withstand,under repeated stress cycles without fracture is called "fatigue strength".
12. Endurance limit:For most of materials there is limiting stress below which a stress or a load may be repeated infinite number of times without causing failure.This limiting stress is known as endurance limit or fatigue limit.
13. Homogeneous material:Homogeneous material means that the material of the member is of the same kind throught  its length.For example,if a beam is made of steel,the material of beam does not change throught the length of the beam.
14. Isotropic material:Isotropic means it possesses the same elastic properties in all the directions.