Berkovich tip

The popular Berkovich now has a very flat profile, with a total included angle of 142.3° and a half angle of 65.27°, measured from the axis to one of the pyramid flats.

This Berkovich tip has the same projected area-to-depth ratio as a Vickers indenter.

The original tip shape was invented by Russian scientist E. S. Berkovich in the USSR around 1950, which has a half angle of 65.03°.

[1][2] 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.

A Berkovich tip, with "a" denoting the half angle
A black-and-white image showing a glossy, triangular pyramid 30° off-axis from a vertical view.
A scanning electron microscope image of a Berkovich tip used in a nanoindenter