How is hardness defined and which parameters should we take into account in a measurement? Hardness is not a fundamental property of a material, but it is the quantity that indicates how mechanically resistant a material (test piece) is to mechanical penetration by another harder body (indenter). Precisely because it is not a fundamental quantity, over the years different methods have been developed with the aim of determining it. Initially, the choice of method depends on the material of the specimen. Then, 1) the magnitude of the force and 2) the time for which the force will be applied must be determined...