1. Strength
It is the ability of material to withstand the external forces without destruction o breaking.
A stronger material can withstand greater load. The internal resistance offered by material against an external force is called stress. The strength of material varies according to type of loading i.e., tensile strength, compressive strength, shearing or torsional strength.
2. Stiffness
It is the ability of material to resist the deformation under the action of external force.
The modulus of elasticly is the measure of stiffness.
3. Elasticity
The elasticity of material is a property by virtue of which deformation caused by applied load is disappeared and material regains its original shape after removal of load.
In other words, the elasticity of material is its power to regain its original shape after deformation, when load is removed, just like rubber.
The elasticity is a tensile property.
4. Plasticity
The plasticity of material is a property, by virtue of which it retains the deformation permanently even after removal of external force causing the deformation action of external forces.
The plastic deformation takes place beyond the elastic range and it is necessary for forging, stamping, and cold working processes.
5. Ductility
The ductility is the property of material, which allows bending, elongation and change of cross-section of metals under the action of external loads.
A ductile material must be strong and plastic, thus material can be drawn into the wire. Mild steel, copper aluminium, nickel, zinc and tin are some ductile materials.
6. Brittleness
It is the property of material by virtue of which the material cannot undergo elastic or plastic deformation, it breaks or fails under the action of external loads.
Glass, cast iron are best examples of brittle material.
7. Malleability
It is special case of ductility which permits the materials to be flatten into the sheets without any crack, under the action of hot or cold working.
A malleable material may be plastic but it is not necessary to be ductile. For an example, the lead can easily be rolled and hammered into their sheets, but cannot be drawn into wire, thus lead is malleable not ductile. The some other malleable materials are soft steel, wrought iron, copper and aluminium.
8. Toughness
It is the property of material to resist the fracture due to high impact loads like hammer below.
It is measured in terms of amount of energy that a material can absorb before actual fracture takes place. For example, under the impact load the mild steel absorbs much more energy, before undergoing any fracture while a glass piece immediately undegoes the fracture. Thus mild steel is tougher metal.
9. Resilence
It is the property of material to absorb energy elastically and to resist impact loads and shocks.
On removal of load, the energy stored is given off exactly as in a spring, when the load is removed.
10. Hardness
It is fundamental property of material and closely related with strength.
It is defined as ability of material which resists scratching, cutting, abrasion, penentration, wear, and machining etc. The hardness is also the ability of material to cut another metal.
11.Machinability
The machinability is the property of material by virture of which the material can undergo various machining process.
A soft material has good machinability. The copper, aluminium and mild steel have good machinability, while hard materials like white cast iron is very less machinable.
12. Formability
The formability is the property of material by virture of which the material can undergo various plastic deformation processes.
13. Weldability.
It is defined as the capacity of metals to be welded into an inseparable joint to form a homogeneous structure after immiscibility of material.
Welding procedure changes metallurgical, chemical, physical and thermal properties of parent metals.
14. Creep.
The creep is progressive permanent deformation with time under the action of constant stresses at high temperature. This property is very important for parts used in I.C. engines, turbines and boilers.
15. Fatigue
The Fatigue is failure of material, when it is subjected to cyclic loads, in which the maximum stress is developed in each cycle, which is well within elastic limit. This phenomenon of material failure under the cycle loading is known as fatigue.
The stress at which the material fails due to fatigue is called as fatigue strength. The fatigue failure always shows a brittle fracture with no appreciable deformation of material in the vicinity of fracture.
