Hardness can be defined as resistance to friction, scratching, cutting or plastic deformation under static or dynamic load. A conical or spherical standard indenter is immersed on material surface, and the trace of indenter formed on the surface is measured. Hardness of the material is inversely proportional to the size of this trace. Hardness testing is simpler and less destructive than the other destructive tests. Hardness of a material is proportional to other mechanical properties.
TS EN ISO 6506-X: Metallic materials – Brinell hardness test
TS EN ISO 6508-X: Metallic materials – Rockwell hardness test
TS EN ISO 6507-X: Metallic materials – Vickers hardness test
TS EN ISO 16859-X: Metallic materials – Leeb hardness test
TS EN ISO 9015-X: Destructive tests on welds in metallic materials – Hardness testing – Part 1: Hardness test on arc welded joints
ASTM E384, ASME IX, AWS, API1104