Knoop indenter

Knoop indenter

[′nüp in′den·tər]
(metallurgy)
A diamond indenter which has a rhombic base with diagonals in a 1:7 ratio and included apical angles of 130° and 172°30′; used in the Knoop indentation test.
References in periodicals archive ?
The Knoop scale is based on a test where the hardness of a particular material is determined by the depth to which the Knoop indenter (a specialty tool based on a diamond) penetrates a particular material's surface.
Glass hardness tests use a Knoop indenter at very low loads ([approximately equal to]1 N) and consequently make very small, shallow impressions.