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Hardness and Tactile Probing Methods

Working group 5.11

Martens hardness (DIN EN ISO 14577-1)

Principle:

The continuous recording of the acting force F and the resulting indentation depth h enables the determination of hardness (Martens hardness, indentation hardness) and of other material parameters, e. g. indentation modulus, indentation creep.

As indenters, the following forms can be used:

  • Vickers indenter
  • Berkovich indenter
  • Hardmetal ball
  • Spherical diamant indenter

These indenters, however, yield different measurement results.

Measurement equation:

For the Vickers- and the Berkovich-shaped indenter, AC can be calculated according to the following formula:

Ac = 26.43 • h2

From this,

is obtained. F in N, h in mm

Application ranges:

Macro range Micro range… Nano range
2 N ≤ F < 30 kN 2 N > F; h > 0.2 µm h ≤ 0.2 µm