[ air-hahr-dn-ing ]
/ ˈɛərˌhɑr dn ɪŋ /

adjective Metallurgy.

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

Origin of air-hardening

First recorded in 1905–10 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for air-hardening

  • This alloy, because hardened simply in air, was called “air-hardening” or “self-hardening.”

    Inventors at Work|George Iles