Carbon steel is a type of steel that contains carbon as the main alloying element

These steels usually have a carbon content of less than 0.25 wt.%. They cannot be hardened by heat treatment (to form martensite) so this is usually achieved by cold work.
Carbon steel is one of the most popular materials used in cookware today. It has several advantages that make it a great choice for a variety of applications,
including being safe for use with food. However, there are a few things to keep in mind when using carbon steel cookware.