1. CLASSIFICATION OF ENGINEERING MATERIALS
TIT GROUP Of INSTITUTIONS, BHOPAL [M.P.]
CLASSIFICATION OF ENGINEERING MATERIALS By
Prof. Kalpana Sachan
Mech. Dept.

2. Engineering materials
CLASSIFICATION OF ENGINEERING MATERIALS
Pig Iron
Wrought Iron
Cast Iron
Steel
Ferrous Materials
Engineering materials
Non-Ferrous Materials
Aluminum & its alloys
Copper & its Alloys
Nickel
Lead
Tin
Zinc

3. Ferrous metals contain iron as the chief (main) constituent, while in nonferrous metals do not contain iron.
Pig iron
Pig iron is a semi-finished ferrous metal produced in a blast furnace by melting iron ore and coke combined with a flux agent like limestone. The flux impurities in the iron to a easily meltable slag.
Pig iron contains 92% iron, 3 to 4 % carbon, and small amounts of sulphur, manganese, phosphorous and other impurities.
The high percentage of carbon content in pig iron makes it to be very hard, however it increases hardness and also brittleness.

4. APPLICATIONS
Forging basic tools, Pig iron is mainly used in making wrought iron, cast iron and steel.
2. Wrought iron
It consists of pure form of iron consisting of about 99.5% iron and a small amount of carbon content ranging from % along with traces of sulphur, manganese, phosphor and silicon.
The low carbon content in wrought iron makes it to be soft, ductile, high elasticity and better tensile strength.
It can be heated and reheated and worked into various shapes, hence the name is wrought iron.
Applications
Fences, gates and railings, balconies, porches and verandas, canopies, lamps etc.,

5. 3. CAST IRON
Cast iron is obtained by re-melting pig iron in a cupola furnace by making certain changes in its composition in molten state.
Cast iron contains 90-92% iron, 2-4.5% carbon, and 1-3% silicon, and smaller amounts of sulphur, manganese, and phosphorous.
With increasing carbon contents, the metal tends to become more brittle thereby avoiding it to be forged, rolled or extruded.
Since casting is the only suitable process for shaping this kind of metal then it is known as cast iron.
It has low melting point, good fluidity, castability, excellent machinability, resistance to defromation and wear resistance.

6. TYPES OF CAST IRON
Gray cast iron
White cast iron
Malleable cast iron
Spheroidal or nodular or ductile cast iron
Gray Cast Iron
It contains approximately 3.2 to 3.5 % carbon, 1.3 to 2.3 % Silicon and small amounts of phosphorous, manganese and sulphur.
It has excellent Castability, Machinability and better wear resistance.
It is used in engine Blocks, Fly wheels, Break Disc and Drums.

7. 2. White Cast Iron :
It contains 1.8 to 3.6% of carbon and 0.5 to 2% of Silicon along with Sulphur, Phosphorous and Manganese in small amounts.
It is used in Rail roads, Brake Shoes, car wheels etc
3. Malleable Cast Iron:
It contains approximately 2 to 3 % carbon, 0.6 to 1.3 % Silicon with phosphorous, manganese and sulphur.
It is used for the manufacturing of Connecting Rods, Compressors, Crank Shafts, transmission gears etc.
4. Spheroidal Graphite (SG) Cast iron:
It contains 3.2 to 4.2 % of carbon, 1.1 to 3.5 % of Silicon along with phosphorous and manganese in small amounts.
It is used in Crank Shafts, Punches, Rolls etc.

8. 4. STEEL
It is an alloy of Iron and Carbon, the carbon content is less than 2%.
The various alloying elements like Sulphur, Phosphorous, manganese, Nickel, copper and chromium etc., are added in small proportions to obtain desirable properties in steel.
TYPES OF STEELS
Depending upon the percentage of Carbon the steels are classified as:
Low carbon steel
Medium carbon steel
High carbon steel

9. Low carbon Steel :
Low carbon steel are also called as mild steel .
It Contains 0.03% to 0.25% of Carbon.
Its properties are Ductile, Good machinability, Malleability
Applications- used to make Valves, Small Gears, Shafts, Automotive body Components
2.Medium carbon Steel:
It Contains 0.25% to 0.59 % of carbon
Good strength and Ductility
Applications—used for making Automotive body Components, crank shaft etc.

10. 3.High carbon Steel:
It Contains 0.6% to 1 % of carbon.
It as Good strength and wear resistance.
It is Brittle and hence difficult to do Machining operations.
Applications---used to make Springs, Haxa Blades, Cold chisels, Hammers etc

11. Alloys of Steel Alloying Steel:
It contains chromium, Molybdenum, phosphorous, Manganese, Vanadium etc, along with the Carbon
These are Excellent in Strength, Corrosion Resistance, Hardness and wear resistance..
Used in manufacturing of air craft, carriage parts, Punches, Bearing Elements, Heavy Gears etc.
2. Tool Steel:( High Speed Steel-HSS):
It contains 5 to 12 % of Tungsten, 3 to 5% Chromium
It is used for making Cutting Tools for metal cutting operations.
3. Stainless Steels:
It an alloy of Carbon and iron with 3 to 25% of chromium
Corrosion Resistance
It is mainly used to make cooking Utensils

12. NON- FERROUS METALS Copper and its alloys:
It is one of the most important non ferrous metals
It is Ductile, Malleable, corrosion resistant and Good Conductor of Heat and electricity.
Two important Copper alloys are:
Brass (Alloy of Copper and Zinc)
Bronze (Alloy of Copper and other than Zinc)

13. 1. Brass: Alloy of Copper and Zinc..
It consist of 5 to 45% of Zinc and Small amount of other elements like tin, lead, silver etc.
Good strength and Ductility
Good heat and Electrical Conductivity
Better wear and Corrosion Resistance
Non Magnetic
Applications
Used in manufacturing of Nuts, Bolts, Threaded Fasteners, Pumps etc

14. 2. Bronze: Alloy of Copper and Elements other than Zinc
It consists of 88% of Copper and 11% of Tin. And various elements like Phosphorous, Lead , aluminium, silicon etc are added to obtain desired properties.
It is soft, Corrosion Resistance and Good Conductor of heat and Electricity better than Steel.
Applications
It is used to produce wires, Rods, Springs, Condenser Tubes, Valve Fittings etc.,

15. 3. Aluminium and its Alloys :
Aluminium is Silverish White non-ferrous alloy.
The alloys of aluminium are Silicon, Phosphorous, Magnesium, Copper and Tin
Light Metal, easily Machineable, High Strength to Weight Ratio, Good Ductility, Good Conductor of Hear and Electricity.
Applications
It is used in Construction of parts in Air Craft, Automotive Vehicles, Space Crafts and Marine Parts.
Electrical applications Such as Electric Wires, Cables, Winding of Motors, Transformers, Generators etc.,

16. 4. Lead and its Alloys:
Lead is Soft, Silvery White non-Ferrous alloy.
It is malleable, Ductile, Corrosion Resistant.
It is poor conductor of electricity and poisonous in nature.
Applications
It is used in Soldering as Solders, Electrical Fuses and Boiler Plugs.

17. A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals and its alloys, generally iron, but also others such as lead or copper.

18. A cupola furnace is a melting device used in foundries that can be used to melt cast iron, Ni-resist iron and some bronzes.
The cupola can be made almost any practical size. The size of a cupola is expressed in diameters and can range from feet.

20. THANK YOU