air-hardening

American  

[air-hahr-dn-ing] / ˈɛərˌhɑr dn ɪŋ /

adjective

Metallurgy.

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

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air hardening British  

noun

1. a process of hardening high-alloy steels by heating and cooling in a current of air Compare oil hardening

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Etymology

Origin of air-hardening

First recorded in 1905–10

Example Sentences

Owing to the air-hardening property of the steel, the drop-forgings should be trimmed while hot.

From The Working of Steel Annealing, Heat Treating and Hardening of Carbon and Alloy Steel by Colvin, Fred H. (Fred Herbert)

The connecting rods are of “H” section, machined all over from forgings of a special air-hardening chrome nickel steel which, after being heat treated has a tensile strength of 280,000 pounds per square inch.

From Aviation Engines Design?Construction?Operation and Repair by Pag?, Victor Wilfred

It was this combination that Mushet used in his well-known "air-hardening" steel.

From The Working of Steel Annealing, Heat Treating and Hardening of Carbon and Alloy Steel by Colvin, Fred H. (Fred Herbert)

The gear steel specified is of the air-hardening type.

From The Working of Steel Annealing, Heat Treating and Hardening of Carbon and Alloy Steel by Colvin, Fred H. (Fred Herbert)