METAL HARDNESS TESTING
Hardness tests have a wide field of use although, as commercial tests, they are perhaps more commonly applied to metals than any other class of material. The results of metal hardness tests may be utilised as follows:-
(1) Similar materials may be graded according to hardness
(2) The quality level of materials or products may be checked or controlled by hardness tests. They may be applied to determine the uniformity of samples of a metal or the uniformity of results of some heat treatment such as forming, alloying, heat treatment or case hardening.
(3) By establishing a correlation between hardness and some other desired property, e.g. tensile strength
(4) Comparison of weld metal hardness to parent metal hardness
Metal hardness test are carried out by Calspec using a portable Equotip hardness tester which gives equivalent hardness readings in Brinell, Vickers and Rockwell. The Equotip hardness tester is designed for testing metallic materials the hardness of which ranges from very low to very high values. Typical applications are large, heavy work pieces which are difficult to access.