Obsolete scrap is the scrap which is relatively pure and its chemical composition is known.
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Steel yield is highest in continuous casting method which significantly reduces scraps.
Copper cannot be removed from steel scraps by the method of conventional refining.
The term degassing is basically employed for optimizing the use of materials used in production of casting components.
Excess of nitrogen in molten casting can cause embrittlement of casting components.
The presence of hydrogen in molten casting strengthens the casting components.
Degassing can be carried out by placing ladle containing liquid metal under vacuum.
Which of the following gases is used in the method of recirculation degassing?
The effectiveness of vacuum treatment is reduced by the increase in surface area of the molten metal exposed to vacuum.
In vacuum treatment of molten metal, temperature of the melt can be decreased.
In vacuum degassing method, low viscosity is considered to have negative influence on the reaction rate.
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