IN DYNAMIC HARDNESS TESTING PROCEDURES, THE INDENTER HITS the specimen surface with impact. The specimen material can thereby be elastically and unelastically deformed. Deformation that arises due to the kinetic energy of the indenter and remains can be measured. In such dynamic-plastic procedures, the hardness value is the quotient of the test force and the indentation size. We distinguish between fall hardness testing and impact hardness testing (see Fig. 22.1).