Specifies the method for Rockwell hardness testing of metallic materials using Rockwell scales that employ preliminary test force, additional test force, and total test force. It covers regular and superficial scales used in quality control and material qualification.

ISO

ISO 6508-1

Revision: 2023

Material testing

Metallic materials — Rockwell hardness test

Specifies the method for Rockwell hardness testing of metallic materials using Rockwell scales that employ preliminary test force, additional test force, and total test force. It covers regular and superficial scales used in quality control and material qualification.

Test method

Indentation is produced by a spheroconical diamond or hardened steel ball indenter under a sequence of forces; depth of residual indentation after removal of additional force determines Rockwell hardness. Different scales (e.g. HRA, HRB, HRC) use defined force combinations and indenter types.

Specimen requirements

Test surface should be smooth, flat, and free of oxide or scale. Minimum thickness depends on scale and indentation size; specimens must support the test without flexing. Anvil and indenter alignment must be maintained.

Further guidance on scale selection and daily verification checks is typically given in laboratory quality manuals aligned with ISO 6508.