VDI/VDE 2625 Blatt 1.1:2025-04 - Draft

The standard describes a procedure for determining the suitability of hardness testing machines according to the Rockwell C method. The procedure takes into account that the measured hardness value is a material parameter and not a physical value. The measured hardness value is the result of an indentation test, which is always accompanied by localised destruction of the material surface and therefore cannot be repeated on the same spot. Proof of suitability is considered taking into account the measurement uncertainty of the hardness testing machine and the specified tolerances from design and production, as well as the scatter of the production process. This standard thus creates a standardised and inter-company basis for objective system assessment for manufacturers and users.