The Vickers hardness test uses a 136° rhomboid diamond indenter to press into the surface of the object to be tested with a specified test force (F). After the specified test force is maintained for a period of time, the test force is removed, and the test piece is measured with a micrometer eyepiece. The indentation diagonal (d) on the surface, calculate the average pressure (N/mm2) on the conical surface area of the indentation, which is the Vickers hardness value. (See Figure 1.1 for details).
Vickers hardness calculation formula: 
formula (1-1)
In the formula:
HV—Vickers hardness
F --N
d--the average length of the two diagonals (d1, d2) of the indentation, mm
The relationship between HV indentation depth h and diagonal line d: h=d/7 formula (1-2)
Note that when the test force is kgf: 
(Formula 1-3)
