a process of hardening high-alloy steels by heating and cooling in a current of air
Compare oil hardening
air-hardening in American English
(ˈɛərˌhɑːrdnɪŋ)
adjective
Metallurgy
noting any metal, esp. alloy steel, that can be hardened from above its transformation point by cooling in air
Word origin
[1905–10]This word is first recorded in the period 1905–10. Other words that entered Englishat around the same time include: airway, jazz, overcall, scrounge, stabilizer