Hardness tests
The laboratory is equipped with single and multipurpose stationary devices for hardness testing:
- Brinell hardness according to standards ČSN EN ISO and ASTM for load to 250 kp.
- Vickers hardnes according to standards ČSN EN ISO and ASTM for load 0,1 to 120 kp.
- Rockwell hardness - all methods - according to standards ČSN EN ISO and ASTM.
Base on these individual methods the laboratory performs also other special hardness test. List of test procedures, for which the laboratory is accredited, see the Appendix to certificate of accreditation.
Hardness tests are characterized by a favourable ratio between the obtained information about condition of the material and difficulty and cost of the test. Often these ones represent the unique way to check the state of finished product without destruction, usually after hardening.
The shape and surface of the test specimens should be guarantee that hardness indents are kept perpendicular to the surface to be tested. Samples of small and irregular shapes can be prepared as metallographic specimens. The quality of the tested surface shall allow with sufficient accuracy to determine the size of indents for Brinell and Vickers hardness. Specimens for Rockwell measuring shall in addition sufficient stiffness, as the depth of indent is measured directly form the depth of indenter penetration.
The hardness testing standards prescribe distances between indents one to other and distances from the edge of the specimen. Each indents takes a certain volume of material into depth and width. These facts should be considered when testing various surface layers either on the surface or on the cut.
To specify the tests we recommend contacting our specialists.