1. PROPERTIES OF MATERIAL
1.STRENGTH- it is the characteristic of the material that alloy it to without and or support external force or
load without rupture.
“The property of the material resist the external load without braking.”
“This property enables material to resist fracture under load”
“External load सहने की अधिकतम क्षमता strength कहलाती है|”
It is very important from design point of view.
Load at ultimate point divided by area of test specimen, is termed as ultimate strength.
2.HARDNESS- the properties of the material resist the pankration. The indentation strength of the material.
Brinell hardness test is used to check hardness .
Brinell hardness numbr =
𝑃
𝜋𝐷/2[𝐷− 𝐷2−𝑑2]
Hare, p=standerd load
D=diameter of steel ball(mm)
d= diameter of intent(mm)
2. 3.ELASTICITY- “The properties of material by which is return it’s original shape after
removing of load.”
it is the property by virtue of which a material deformed under the load is enabled to return
to it’s original dimension when the load is removed.”
If body regains completely its original shape it is called perfectly elastic body.
Elastic limit marks the partial break down of elastic beyond which removal of load result in
a degree of permanent deformation.
Steel, Al, Cu, concrete may be considered to be perfectly elastic within certain limit
4.PLASTICITY- “Material take permanent deformation after removed the load.”
“the characteristic of material by which it undergoes inelastic strain beyond those at the
elastic limit is known as plasticity”
This property is particularly useful in operation of pressing and forging.
When large deformation occurs in a ductile material loaded in plastic region , the material
is said to undergo plastic flow.
3. 5.DUCTILITY- It is the property which permits a material to be draw out longitudinally to a reduced
section, under the action of tensile force.
“the property of material by which it can draw into thin wire any rupture”
A ductile material must posses a high degree of plasticity and strength.
Ductile material must have low degree of elasticity.
This is useful in wire drawing.
6.MALLEABLITY- It is the property of a material which permits the material to be extended in all
directions without rupture.
It can convert into thin sheet by beaten by hammer without any rupture.
A malleable material possesses a high degree of plasticity , but not necessarily great strength.
7.BRITTLENESS- It is the property of a material due to which material breaks with little permanent
distortion.
“It is the lack of ductility”
In brittle material failure take place under load without significant deformation
Ordinary glass is nearly ideal brittle material.
Cast iron, concrete and ceramic material are brittle material.
4. TOUGHNESS- It can bend twist and stretched under a high stress without an rupture.
it is he property of material which enables it to absorb energy without fracture.
Bend test used for common comparative test for toughness.
It’s the ability of a material of a resist indentation or surface abrasion.
STIFFNESS- property of a material which return to its original shape or form after an applied load is
removed.
ककसी मटेरियल में ककसी अन्य मटेरियल की तुलना में होने वाला deformation उसकी stiffness को
show किता है|
Material में प्रतत इकाई deformation उत्पन्न किने क
े ललए आवश्यक stress को stiffness कहते है|
RESILIENCE- Ability of a material to absorb energy in elastic region when it is strained.
मटेरियल का इलास्टटक रूप में उर्ाा अवशोषित किक
े िखने की क्षमता को Resilience कहते है|
LUSTRE- The property of a material by virtue of which is can shine or safe glow.
MACHINABLITY- Machinability is a characteristic of a material, such as a metal, that makes it easy to
drill,shape,cut,grind etc. The term refers to the ease with which we can machine , for example a
metal.
5. FATIGUE- it is caused by repeated application of stress the metal. It is the failure of a material by fracture when subjected
to a cyclic stress.
Material का बाि-बाि cyclic loading ककये र्ाने पि fail हो र्ाना |
CREEP- it’s property of a material by virtue of which it deforms continuously under a steady load.
िातुओ तथा अिातुओ में लगाताि Stress लगे िहने क
े कािण या लम्बे समय से load लगे िहने क
े कािण होने वाले slow
plastic deformation को Creep कहते है|