Knoop hardness

\ ˈnüp- \

Definition of Knoop hardness

: the relative hardness of a material (as a metal) that is determined by the depth to which the bluntly pointed diamond pyramid of a special instrument will penetrate it

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History and Etymology for Knoop hardness

after F. Knoop, 20th century American chemist

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Cite this Entry

“Knoop hardness.” Dictionary, Merriam-Webster, Accessed 25 May. 2020.

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