1.1 ,This test method covers the hardness testing of cemented carbides by use of a Rockwell hardness tester performing tests in the Rockwell HRA scale (regular scale, diamond indenter, 10 kgf (98.07 N) preliminary test force, and 60 kgf (588.4 N) total test force in the range of Rockwell 80 HRA and above. Also covered are the procedures for the testing and selection of diamond indenters, the management and traceability of the four levels of standardized test blocks, and the making and calibration of Primary, Secondary, and Working standardized test blocks.