PRINCIPLES OF METALLURGY

METALLURGY PRINCIPLES

metallurgy is nothing but the materials science that deals with physical and chemical behavior of the metallic elements and metallic compounds, mixture; and it is the process of extracting metals from the ores is called metallurgy. and also it is dealt with the purification and manufacture of metals.

Minerals:

the naturally occurring compounds which are previously mixed with soil, stones, rock, etc,.

Ore:

ore is the extraction of metals from the minerals. the process of removing the gangue from the ore is nothing but the concentration of ore.

METALS:
metals are elements formed by positive ions by the loss of electrons.

NON METALS:
these are elements which are formed by the negative ions by the gaining of electrons. 

Gangue:

it is the waste substance in the ore.consists of impurities like sand(silica)and mud.

Flux:

it is used to extract the gangue from the ore.

Slag:

it is a fusible product formed by the reaction of flux with gangue is called slag.

ALLOY:
alloy is a homogeneous mixture of metals or mixture of metal and non-metals in a definite proportion in their molten state.

SOME IMPORTANT ALLOYS:

BRASS:
copper=70%
zinc=30%

GERMAN SILVER:
copper=50%
zinc=30%
nickel=20%

NICHROME:

nickel=60%
chromium=15%
iron=25%

METHODS OF METALLURGY;

1. -handpicking: the ore is separated from the main stock and also separation process is done through the hand by comparing the luster, color, size of the particle.
2. -levigation: it is the process of grinding an insoluble substance to a fine powder, while it is in a wet state. the material is introduced to the mill, the fine powder present in it is suspended.
3. -froth flotation :

SMELTING PROCESS:

Metal smelting is that the process of making metal by heating metal ore. The ore be it iron, copper, or tin, is mixed with carbon and the mixture is heated to the point of conversion into a liquid form.

CALCINATION PROCESS:

it is the process of removing the impurities by the heating high temperatures in the absence of oxygen.

ROASTING PROCESS:

it is the process of removing the impurities by the heating high temperatures in the presence of oxygen.

ELECTROLYTIC REFINING:

Electrolytic refining is a process of refining a metal (mainly copper) by the electrolysis. As far as the mechanism of the process is concerned, during electrolysis, a large chunk or slab of impure metal is used as the anode with a thin strip of pure metal at the cathode. In this setup, an electrolyte (metal salt aqueous solution) depending on the metal is often used. The clean or pure metal is formed at the cathode when the electrical current of a sufficient voltage is applied by dissolving impure metal at the anode. Electrolytic refining is additionally sometimes mentioned as Electrorefining.