This part of ISO 14577 specifies the procedure for the instrumented penetrant test to determine the hardness and other material parameters for the following three ranges: - Macro range: 2 N less than or equal to F less than or equal to 30 kN; - micro range: 2 N greater than F; h greater than 0.2 µm; - Nano range: h less than or equal to 0.2 µm. In the nano range, the mechanical deformation depends heavily on the real geometry of the indenter tip and the calculated material parameters are significantly influenced by the contact surface function of the indenter used in the testing machine. Therefore a careful calibration of both the testing machine and the indenter geometry is necessary in order to obtain an acceptable comparative precision of the material parameters determined with different testing machines. The macro and micro ranges differ in terms of the test forces with regard to the penetration depth. It should be noted that the micro area is limited upwards by the test force (2 N) and downwards by a penetration depth of 0.2 µm. The determination of the hardness and the other material parameters is contained in Appendix A. Damage to the indenter is possible at high contact pressures. For this reason, penetrators made of hard metal are often used in the macro area. In the case of specimens with very high hardness and very high modulus of elasticity, permanent deformation of the indenter can occur and can be detected with the help of suitable reference materials. It is necessary that the corresponding influence on the test result is taken into account. This test method can also be used for thin metallic and non-metallic coatings and for non-metals. In this case, it is recommended that the specifications contained in the relevant standards are observed (see also 6.3 and ISO 14577-4).
