temper color

noun

Metallurgy.

1. any of the colors appearing on the surface of clean, unoxidized steel heated in air, from pale yellow at the coolest to dark blue at the hottest: used as an approximate indication of temperature.

Example Sentences

If there is a distinct boundary line of temper color between the hard cutting edge and softer shank portion, it will be very apt to break at or near that line.

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