Hardness testing of metals.

Hardness is the mechanical resistance that a material opposes to the mechanical penetration of a harder, a softer, or an equally hard test specimen. Within the various stages of the manufacturing process, the hardness test is an indispensable step in the quality assurance of a product. Depending on the type of action, a distinction is made between different types of hardness. Various test methods are available for testing the hardness of metals.

The hardness test method which is suitable for your project depends, among other things, on the material to be measured.

All hardness testing methods have a common basic principle:
A standardized test body – for example a diamond pyramid / cone or hard metal ball – is pressed onto the surface of the material. Then the surface or the penetration depth of a test body is measured.
Hardness is often a good indicator of the tensile and wear properties of a material.
The definition of hardness differs from that of strength.
This represents the resistance of a material to deformation.
The hardness, along with strength, ductility, rigidity, fracture toughness, density and melting temperature, is one of the material properties.

In the Brinell hardness test, a hard metal ball (tungsten carbide) with a certain ball diameter is pressed as an indenter under a defined force vertically into the surface of a sample. We use the Brinell hardness test to check the hardness of ferrous and non-ferrous materials. With the Brinell hardness test, however, only soft to medium-hard workpieces can be tested for hardness.

In the Vickers hardness test (Vickers hardness), a diamond pyramid with a square base and a surface angle of 136 ° is pressed vertically into the specimen under a defined force. The hardness measurement is used to check the hardness properties of all metals.

The Vickers hardness measurement is particularly suitable for measurements with low test forces for thin and small parts, or in some cases also layers or workpieces with surface treatment.