The instrumented indentation test method is used for the determination of hardness and other material parameters. The result of the test is the continuous load/indentation depth curve during the complete test cycle. By analyzing this curve at several points, comprehensive mechanical materials properties can be determined within the scope of a single test. This method covers all hardness grades from thermoplastic films to very hard metals, enabling improved comparability of material behavior.
The force-indentation depth curve and different sequences of the loading process allow more comprehensive description of mechanical material properties, including:
- Plastic and elastic portions of the indentation energy
- Martens hardness HM
- Volume hardness HMs
- Indentation hardness HiT
- Elastic indentation module EiT
- Creep behavior
- Creep relaxation behavior
- Can be used for all materials.
- Capable of automation.
- Use in production checks.
- Determination of hardness value from elastic and plastic deformation.
- Hardness value independent of test load for indentation depths ≥ 10 μm.
- Additional information on the material provided by force/indentation depth curve.
- Additional characteristics relating to mechanical material behavior can be determined (material relaxation/creep, elastic and plastic portions of the indentation energy, plastic hardness, elastic indentation modulus).
- Decreasing the degree of indentation places increased demands on the quality of the specimen surface (indentation depth ≥ 20 · mean surface roughness).
- Susceptible to vibrations, particularly in indentation range h< 15 µm.
- Possibility of error due to elastic and permanent displacement of specimen and of components in the force flow during test cycle.
- Sensitivity of method to deviations in indenter shape, particularly in area of tip.