Rockwell hardness


Rock·​well hardness
: the hardness of a metal or alloy measured by an apparatus in which a diamond-pointed cone is pressed into the metal to a standard depth to determine the relative resistance to penetration as indicated automatically by a number on a dial

Word History


after Stanley P. Rockwell, 20th century American metallurgist

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Dictionary Entries Near Rockwell hardness

Cite this Entry

“Rockwell hardness.” Dictionary, Merriam-Webster, Accessed 19 Jul. 2024.

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