PHYSICAL AND MECHANICAL PROPERTIES OF METALS

 Physical and mechanical properties of metals

.different physical and mechanical properties of materials

. Charactor of the mechanical properties of metals

Properties of metals

Matels have different properties. Depending on the type of application, different metals are selected.

Physical properties of metals

Colour

Weight /specific gravity

Structure

Conductivity

Magnetic property

Fusibility

Colour

Different metals have different colours. For example coper is of a distinctive colour. Mild steel of a  blue/black sheen

Weight

Metals differ based on their weight. A metal,like aluminum, weight lighter(specific gravity 2.8) than many others, and a metal, like lead, is heavy (specific gravity 9)

Structure

Generally metals can also be differentiated by their internal microstructure. Metals like wrought iron and aluminum will have a fibrous structure, and metals like cast iron and bronze will have a granular structure.

Conductivity

Thermal conductivity and electrical conductivity are the measure of the ability of a material to conduct heat and electricity. Conductivity will vary from metal to metal. Copper and aluminum are good conductors of heat and electricity.

Magnetic property

A metal is said to process magnetic property, if it is attracted by a magnet.

Almost all ferrous metals, excepting some types of stainless steel, can be attracted by a magnet and all nonferrous metals and their alloys will not be attracted by a magnet.

Fusibility

It is the property possessed by a metal by virtue of which it melts when heat is applied. Many materials are subject to the transformation in shape (i. e) form solid to liquid at different temparature. Tin had a low melting temaprature and tungsten melts at a high temaprature.

Tin melts at 232°c

Tungsten melts at 3370°c

Mechanical properties

The mechanical properties of a metal are

Ductility

Malleability

Hardness

Brittleness

Toughness

Tenacity

Elasticity

Ductility

A metal is said to be ductile when it may be drawn out in tension without rupture. Wire drawing depends upon ductility for its successful operation. A ductile metal must be both strong and plastic. Copper and alumnium are good examples of ductile metals.

Malleability

Malleability is the property of permanently extending in all directions without rupture by hammering, rolling etc. To change its size and shape. Lead is a very malleable metal.

Hardness

Hardness is a measure of a metals ability to withstand scratching, wear, abrasion and  penetrstion.

Brittleness

Brittleness is that property of a metal which permits no permanent distortion before breaking. Cast iron is an example of a brittle metal, and it will break rather than bend under shock or impact.

Toughness

Toughness is the property of a metal to withstand shock or impact. Toughness is the property opposite to brittleness. Wrought iron is an example of  a tough metal

Tenacity

Tenacity of a metal is its ability to resist the effect of tensile forces without rupture. Mild steel, wrought iron and copper are example of tenacious metals.

Elasticity

Elasticity of  a metal is its power of returning to its original shape after the applied force is released. Properly heat treated spring is a good example of elasticity.