The diagonal of the resulting indention is measured under a microscope and the Vickers Hardness value read from a conversion table and their average calculated. The area of the sloping surface of the indentation is calculated. The Vickers hardness is the quotient obtained by dividing the kgf load by the square mm area of indentation.
F= Load in kgf
d = Arithmetic mean of the two diagonals, d1 and d2in mm
HV = Vickers hardness
The advantages of the Vickers hardness test are that extremely accurate readings can be taken, and just one type of indenter is used for all types of metals and surface treatments. The Vickers method is capable of testing the softest and hardest of materials, under varying loads and we can easily testing very thin materials like foils or measuring the surface of a part, small parts or small areas, measuring individual micro structures, or measuring the depth of case hardening by sectioning a part and making a series of indentations to describe a profile of the change in hardness.
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