ISO HARDNESS STANDARDS INDENTATION HARDNESS TESTS AND HARDNESS STANDARD BLOCKS

Abstract − ISO standards for hardness are established from metrological standards for force, length, etc. and daily control requirements via hardness standard blocks. The authors have already stated that the unification of loading speed via ISO standards is important both industrially and economically. In consideration of the international importance of ISO standards for hardness testing, the authors review the current ISO specifications in this report, particularly their definition of loading speed, tolerances for Rockwell reference loads, and other test-block requirements, based on our own experiments. Although it may be necessary to have continuous experimental findings using various hardness testers and test blocks, the following conclusions can be said at present. (1) As a result of reviewing the basis of defining test forc