C45 steel is an unalloyed medium carbon engineering steel which has 0.42%-0.5% Carbon.It offers moderate tensile strengths,wear resistance and good machinability.this material is capable of through hardening by quenching and tempering on limited sections,and also can be flame or induction hardened to surface hardness Min 55HRC.C45 is generally supplied in an untreated or normalised condition with a typical tensile strength range 570 – 700 Mpa and Brinell hardness range 170 – 210.

C55 steel is an unalloyed medium carbon engineering steel which has 0.52%-0.6% Carbon as per EN10083 standard.It will obtain high hardness and high strength  after hardening due to the relatively high carbon content,and also can be flame or induction hardened to surface hardness Min 58HRC.C55 steel is generally supplied in an untreated or normalised condition.

C60 steel is an unalloyed medium carbon engineering steel which has 0.57%-0.65% Carbon as per EN10083 standard.It has characteristics similar to that of c55 carbon steel which has high hardness and high strength  after hardening.C60 is difficult to weld,and machinability is poor due to high carbon content.This steel is generally supplied in an untreated or normalised condition.