adjective. noting or pertaining to any of various steels that harden after heating without quenching or other treatment.

What is meant by the term hardening?

Hardening is the process by which something becomes harder or is made harder. Hardening may refer to: Hardening (metallurgy), a process used to increase the hardness of a metal.

What does air hardening mean?

noting any metal, especially alloy steel, that can be hardened from above its transformation point by cooling in air. ...