This category of steel is distinctive from other categories due to its reliance on carbon as the main alloying element. The percentage of carbon normally remains in the range of 0.12 % to 2 % According to the American Iron and Steel Institute (AISI), carbon steel is defined as follows. “ Steel is considered to be carbon steel when no minimum content is specified or required for chromium, cobalt, molybdenum, nickel, niobium, titanium, tungsten, vanadium or any other element to be added to obtain a desired alloying effect; when the specified minimum inclusion of copper does not exceed 0.40 %; or when the maximum content specified for any of the following elements does not exceed the percentages noted: manganese 0.60, silicon 0.60, copper 0.60”.

Note:- 

Carbon plays a very vital role in any type of steel. As the percentage of carbon increases, it gives the steel an ability to become harder and stronger after heat treatment. On the other side, an increase in carbon content reduces ductility (ability to be drawn into wires) and weldability.

The available grade is given below :-

C45 is an unalloyed medium carbon steel grade with reasonable tensile strength. C45 is widely used for applications that require better properties than mild steel but does not justify the costs of an alloy steel. C45 can be flame or induction-hardened to produce a good surface hardness of 52 HRc with moderate wears resistance.