METALS CHAPTER NOTES PART-1, Ferrous metals

METAL

METALS CHAPTER PART - 1

Most important Discussion Below- 

Metals which contain iron as a major content are called ferrous metals.

The ferrous metals used commonly are –   1. Pig iron

2. Cast iron

3. Wrought iron

4. Still and alloy steel

PIG IRON

Pig iron is the product of blast furnace . Pig iron is obtained by the Chemical reduction of iron ore, This process of reduction of the iron ore to Pig iron is known as SMELTING.

Limestone is the most commonly used flux in the blast furnace.

 

                                          Pig iron contains about 3-5% carbon . It is soft and brittle it lacks strength, ductility and resistance to shock. It is used for making steel and cast iron.;

 

CAST IRON

 

Cast iron is the product of Cupola furnace. Cast iron contains about 2% to 4% Carbon. The main properties of cast iron-

                      i.        It is hard and brittle.

                    ii.        It is neither malleable nor ductile.

                   iii.        It has high compressive strength and low tensile strength .

                   iv.        It’s melting point is about 1130 digree C , it is comparatively easy to melt and cast.

 

 

 

 

Different type of cast irons are – a. Grey cast iron

                               b. white cast iron

                               c. Malleable cast iron , d. Nodular cast iron

GREY CAST IRON

This is widely used for the casting of machinery part and can be machined easily. Machine base slide ways, tables are made of cast iron because it is dimensonaly stable . Grey cast iron is widely used for machine tools because of its ability to reduce vibration and minimize to catter and grey cast iron is a rigid metal.

 

WHITE CAST IRON

This is very hard and is very difficult to machine white cast iron cannot be welded. This is mainly used in the manufacture of wrought iron.

 

MALLEABLE CAST IRON

It is obtained by annealing white cast iron at about 830°C for several days. Malleable cast iron has increased ductility, tensile strength and toughness.

 

Nodular cast iron

This is very similar to malleable cast iron. But this is produced  without any heat treatment. Modular cast iron also known as ductile iron, spheroidal graphite iron. This is good machinability, resistance to wear, low melting point and hardness. Malleable and nodular castings are used for machine parts where there is a higher tensile stress.

 

 

WROUGHT IRON

Wrought iron is the purest from of iron. Wrought iron 99.9% of iron contain. It is produced from pig iron is a PUDDLING FURNACE.