Engineering Materials
Thermoplastic materials are those materials which

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
Are flexible and can withstand considerable wear under suitable conditions

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Engineering Materials
Malleable cast iron

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

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Engineering Materials
Steel contains

Elements like phosphorus, sulphur and silicon in varying quantities
50% or more iron
Alloying elements like chromium, tungsten nickel and copper
80% or more iron

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