BS EN ISO 4545-3:2015 pdf download.Metallic materials - Knoop hardness test Part 3: Calibration of reference blocks.
3.7 To verify that no material is subsequenuy removed from the reference block, the thickness at the lime of calibration shall be marked on It. to the nearest 0,1 mm. or an identifying mark shall be made on the test surface [see 81 e)J.
4 Calibration machine
4.1 In addition to fulfdllng the general requirements specified m ISO 4545-2, the calibration machine shall also meet the requirements given In 42 to 4.7.
NOTE Exanles of procedures for adjustment of illumwwhon systems are given in Annex A.
4.2 The machine shall have been direcUy verified in intervals not exceeding 12 months.
Direct verification wivotves:
a) calibration of the test force:
b) verification of the indenter;
C) calibration and verification of the diagonal measuring system;
d) verification of the testing cycle.
4.3 The instruments used for verification and caloration shall be traceable to national standards.
4.4 Each test force shall be verified at 3 different positions of the pkinger. spaced at approximately equal increments covering the limits of travel used during testing At each position, the force shall be measured three times using an elastic proving device according to ISO 376 Class 0,5 or better, or by another method having the some or better accuracy. Each measurement shall agree with the nominal value to withm ± 0,5 %.
4.5 The indenter shall comply with ISO 4545-2 clause 4.3 and meet the following requirements:
a) The angle i (see 1504545-1. Figure 1), between opposite edges at the vertex of the diamond pyiarnid, shall be (130 ± 0,1).
b) The angle between the axis of the diamond pyramid and the axis of the Indenter holder (normal to the seating surface) shall not exceed 0.3. The four faces shall meet at a point: the length of any common Junction between opposite faces being less than 0,000 3 mm.
4.6 The diagonal measuring system shal be verified at a minimum of five evenly spaced intervals over each working range against an accurately ruled stage micrometer. The accuracy of the line intervals on the stage micrometer shall be 0.000 1 mm or 0.05 %. whichever is greater.
The maximum permissible error of the diagonal measuring system at each interval shall be ± 0.000 2 mm or 025 % wtiechever is greater.
4 Calibration machine
4.1 In addition to fulfdllng the general requirements specified m ISO 4545-2, the calibration machine shall also meet the requirements given In 42 to 4.7.
NOTE Exanles of procedures for adjustment of illumwwhon systems are given in Annex A.
4.2 The machine shall have been direcUy verified in intervals not exceeding 12 months.
Direct verification wivotves:
a) calibration of the test force:
b) verification of the indenter;
C) calibration and verification of the diagonal measuring system;
d) verification of the testing cycle.
4.3 The instruments used for verification and caloration shall be traceable to national standards.
4.4 Each test force shall be verified at 3 different positions of the pkinger. spaced at approximately equal increments covering the limits of travel used during testing At each position, the force shall be measured three times using an elastic proving device according to ISO 376 Class 0,5 or better, or by another method having the some or better accuracy. Each measurement shall agree with the nominal value to withm ± 0,5 %.
4.5 The indenter shall comply with ISO 4545-2 clause 4.3 and meet the following requirements:
a) The angle i (see 1504545-1. Figure 1), between opposite edges at the vertex of the diamond pyiarnid, shall be (130 ± 0,1).
b) The angle between the axis of the diamond pyramid and the axis of the Indenter holder (normal to the seating surface) shall not exceed 0.3. The four faces shall meet at a point: the length of any common Junction between opposite faces being less than 0,000 3 mm.
4.6 The diagonal measuring system shal be verified at a minimum of five evenly spaced intervals over each working range against an accurately ruled stage micrometer. The accuracy of the line intervals on the stage micrometer shall be 0.000 1 mm or 0.05 %. whichever is greater.
The maximum permissible error of the diagonal measuring system at each interval shall be ± 0.000 2 mm or 025 % wtiechever is greater.
