Classification Of Alloy Steels

Alloy steel may be classified according to their chemical composition, structural class and purpose.

Classification according to chemical composition :

In this aspect alloy steels are divided into three-component steels , containing one alloying element in addition to iron and carbon : four component steels, containing two alloying elements, etc.

Classification according to structural class :

On the basis of the structure obtained when specimens of small cross-section are cooled in air and they are classified as :

a) pearlite

b) martensitic

c) austenitic

d) ferritic

e) carbidic

Classification according to purpose :

As to the uses for which their properties fit them alloy steels can be classified :

a) Structural steels.

b) Tool steels.

c) Steels with special physical properties.

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