<http://www.round-bars.com/products/c55-steel/#webpage>
<http://schema.org/description>
"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."
<http://www.round-bars.com/products/c55-steel/?portfolioCats=12%2C13%2C19%2C6>