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Knoop hardness test

A micro-hardness testing method using an elongated, rhombic diamond pyramid that produces particularly shallow indentations. It is exceptionally well suited for thin layers or surface-hardened zones.

Knoop hardness testing uses an elongated diamond pyramid indenter. The impression is flat and narrow, ideal for thin layers or edge zones at the weld transition. You measure the length of the impression, not the depth. Make sure the surface is clean and flat, otherwise you'll distort the result. For coarse microstructures or very rough surfaces, this method is less suitable; better use Vickers.

MetallurgieSchweißtechnik

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