A Berkovich tip is a type of nanoindenter tip used for testing the indentation hardness of a material. It is a three-sided pyramid which is geometrically self similar. It has a very flat profile, with a total included angle of 142.3 degrees and a half angle of 65.35 degrees, measured from the axis to one of the pyramid flats. The Berkovich tip has the same projected area-to-depth ratio as a Vickers indenter. The tip shape was invented by Russian scientist E.S. Berkovich in the USSR c. 1950.
As it is three sided, it is easier to grind these tips to a sharp point and so is more readily employed for nanoindentation tests. It is typically used to measure bulk materials and films greater than 100 nanometres (3.9×10−6 in) thick.
Famous quotes containing the word tip:
“Lolita, light of my life, fire of my loins. My sin, my soul. Lo-lee-ta: the tip of the tongue taking a trip of three steps down the palate to tap, at three, on the teeth. Lo. Lee. Ta.”
—Vladimir Nabokov (1899–1977)