Elasticity : Elasticity of a material is its power of coming back to its original position after deformation when the stress or load is removed.Elasticity is a tensile property of its material.
Proportional Limit : It is the maximum stress under which a material will maintain a perfectly uniform rate of strain to stress.
Elastic Limit : The greatest stress that a material can endure without taking up some permanent set is called elastic limit.
Stiffness : It is the property of a material due to which it is capable of resisting deflection or elastic deformation under applied loads.also called rigidity. The degree of stiffness of a material is indicated by the young’s modulus. The steel beam is stiffer or more rigid than aluminium beam.
Plasticity : The plasticity of a material is its ability to change some degree of permanent deformation without failure. This property is widely used in several mechanical processes like forming, shaping, extruding, rolling etc. Due to this properties various metal can be transformed into different products of required shape and size. This conversion into desired shape and size is effected either by the application of pressure , heat or both. Plasticity increase with increase in temp.
Malleability : Malleability of a material is its ability to be flattened into their sheets without creaking by hot or cold working. Aluminum, copper, tin lead steel etc are malleable metals.
Ductility : Ductility is that property of a material, which enables it to draw out into thin wire. Mild steel is a ductile material. The percent elongation and the reduction in area in tension is often used as empirical measures of ductility.
Brittleness : The brittleness of a material is the property of breaking without much permanent distortion. There are many materials, which break or fail before much deformation take place. Such materials are brittle e.g. glass, cast iron. Therefore a non-ductile material is said to be a brittle material. Usually the tensile strength of brittle materials is only a fraction of their compressive strength. A brittle material should not be considered as lacking in strength. It only shows the lack of plasticity.
Toughness : Toughness is a measure of the amount of energy a material can absorb before actual fracture or failure takes place. The toughness of a material is its ability to withstand both plastic and elastic deformation. “The work or energy a material absorbs is called modulus of toughness”
For Ex: If a load is suddenly applied to a piece of mild steel and then to a piece of glass the mild steel will absorb much more energy before failure occurs. Thus mild steel is said to be much tougher than a glass.
