Rockwell hardness

Rock·​well hardness | \ ˈräˌkwel-, -kwəl-\

Definition of Rockwell 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

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History and Etymology for Rockwell hardness

after Stanley P. Rockwell, 20th century American metallurgist

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to affect and impair by alcohol or a drug

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