Engineering Materials
Vanadium in high speed steels

Promotes retention of austenite
Promotes decarburisation
Forms very hard carbides and thus increases wear resistance
Provides high hot hardness

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Engineering Materials
In process annealing, the hypo eutectoid steel is

Heated from 30°C to 50°C above the upper critical temperature and then cooled suddenly in a suitable cooling medium
Heated from 30°C to 50°C above the upper critical temperature and then cooled slowly in the furnace
Heated from 30°C to 50°C above the upper critical temperature and then cooled in still air
Heated below or closes to the lower critical temperature and then cooled slowly

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Engineering Materials
Grey cast iron

Is also known as chilled cast iron is obtained by cooling rapidly. It is almost unmachinable
Is produced by small additions o magnesium (or cerium) in the ladle Graphite is in nodular or spheroidal form and is well dispersed throughout the material
Is produced by annealing process. I 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

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Engineering Materials
In spheroidising process, the steel is

Heated up to the lower critical temperature and then cooled in still air
None of these
Heated below the lower critical temperature and then cooled slowly
Heated slightly above the lower critical temperature and then cooled slowly to a temperature of 600°C

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