Engineering Materials
Free carbon in iron makes the metal

Hard and gives a coarse grained crystalline structure
Soft and gives a fine grained crystalline structure
Soft and gives a coarse grained crystalline structure
Hard and gives a fine grained crystalline structure

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Engineering Materials
Thermoplastic materials are those materials which

Are flexible and can withstand considerable wear under suitable conditions
Are formed into shape under heat and pressure and results in a permanently hard product
Do not become hard with the application of heat and pressure and no chemical change occurs
Are used as a friction lining for clutches and brakes

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Engineering Materials
Ductile cast iron

Is also known as chilled cast iron and is obtained by cooling rapidly. It is almost unmachinable
Contains 1.7 to 3.5% carbon in Free State and is obtained by the slow cooling of molten cast iron
Is produced by annealing process. It is soft, tough and easily machined metal
Is produced by small additions of magnesium (or creium) in the ladle. Graphite is in nodular or spheroidal form and is well dispersed throughout the material

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