Engineering Materials
White cast iron

Is also known as chilled cast iron and is obtained by cooling rapidly. It is almost unmachinable
Is produced by annealing process. It is soft, tough and easily machined metal
Contains 1.7 to 3.5% carbon in Free State and is obtained by the slow cooling of molten cast iron
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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Engineering Materials
Cobalt in steel

Refines grain size and produces less tendency to carburisation, improve corrosion and heat resistant proper ties
Improves wear resistance, cutting ability and toughness
Improves cutting ability and reduce hardenability
Gives ductility, toughness, tensile strength and anti corrosion property

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Engineering Materials
Recrystallization temperature is one

At which crystals first start forming from molten metal when it is cooled
At which new spherical crystals first begin to form from the old deformed one when a strained metal is heated
At which change of allotropic form takes place
At which crystals grow bigger in size

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Engineering Materials
Aluminium bronze contains

90% magnesium and 9% aluminium with some copper
94% aluminium, 4% copper and 0.5% Mn, Mg, Si and Fe
10% aluminium and 90% copper
92.5% aluminium, 4% copper, 2% nickel, and 1.5% Mg

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