According to AISI (The American Iron and Steel Institute) carbon steel is that steel where minimum amount of chromium, molybdenum, titanium, cobalt is either specified or required. These metals are added to get an alloy as needed. Also when the minimum amount of copper does not exceed 0.4 % as specified, is referred to as carbon steel.
STEELS CAN BE CLASSIFIED BY THE FOLLOWING DIFFERENT SYSTEMS BASED ON:-
1. The manufacturing methods like basic oxygen process, open hearth or electric furnace methods.
2. The composition as in carbon, low-alloy or stainless steel.
3. The finishing method like hot or cold rolling.
4. The heat treatment like annealing, thermomechanical processing and quenching and tempering.
5. The required strength level according to the ASTM standards.