ISO 14577-2:2015 pdf free

ISO 14577-2:2015 pdf free.Metallic materials – Instrumented indentation test for hardness and materials parameters
Indirect verification should be carried out at the temperature of use by means of reference blocks calibrated in accordance with ISO 14577-3, or within the temperature at for which the calibration of the reference blocks is valid, typically (23±5) °C. Indirect verification using a reference material shall be made to ensure the direct verification is valid and that no damage or contamination has occurred to the indenter tip.
Before measuring on the reference block, it is recommended to inspect and clean the indenter first using the procedure recommended in ISO 14577-1:2015, Annex D. If the results of these initial indentations indicate the presence of contamination or damage, then the indenter should be cleaned again before further trial indents are made. If after further cleaning, indentation into the reference material still indicates the presence of contamination or damage, then inspection with an optical microscope at a magnification of 400x is recommended. Detection of sub-microscopic damage or contamination is possible using appropriate microscopy of indents or the indenter. Where damage is detected, the indenter shall be replaced.
For an indirect validation decision tree, see Figure 7. The procedures for the determination of the machine compliance, CF, and the area function, Ap(hc), calibration/verification shall be implemented before a new indenter is used. If, after applying the currently valid correction for machine compliance and indentation area function (obtained using a variable epsilon and a radial displacement correction, ISO 14577-1:2015, Annex I), a measured value from a reference block deviates from the certified value of the test piece by more than the maximum permissible amount of the limits specified in Table 7 (see Note 2) and repetition of the procedure using a newly verified and certified indenter and valid machine compliance correction corresponding to that indenter) also fails to reproduce the certified value, the testing machine shall be serviced and a full, direct calibration be performed.
NOTE 1 The use of control charts is a sensitive way to determine changes in performances before a control limit is breached (see Annex C).ISO 14577-2 pdf download.