GB/T 4341.3-2016Metallic materials - Shore hardness test - Part 3: Calibration of reference blocks (English PDF)

3.1

The standard block shall be specially manufactured and the manufacturing process shall be such that the standard block obtains the necessary homogeneity, the stability of the tissue and the hardness

Uniformity.

3.2

The geometric dimensions of the standard block are shown in Table 1.

Table 1 The geometry of the standard block is in millimeters

Standard block shape diameter length × width thickness

Rectangular - 65 × 52 15 ± 0.1

Round 64 - 15 ± 0.1 3.3 standard block test surface parallel to the bearing surface of 0.02mm/50mm.

3.4

Standard block test surface and the bearing surface of the flatness of 0.01mm.

3.5

hardness range of 91HSD ~ 99HSD, 56HSD ~ 64HSD standard block, the test surface of the surface roughness Ra the largest

A value of 0.05µm; hardness range of 26HSD ~ 34HSD standard block, the test surface of the surface roughness Ra maximum

0.1 µm; the maximum surface roughness Ra of the standard block support surface is 0.8 µm and the sampling length is l = 0.80 µm (see GB/T 3505-

2009 3.1.9).

3.6

The standard block shall not be magnetized and shall ensure that the standard block is demagnetized after its manufacturing process has been completed (before calibration).

3.7

standard block test surface and bearing surface should be no corrosion, cracks, abrasions, scratches, electrical and other defects.

3.8

standard block of various signs, the value should be clear and accurate.

3.9

To ensure long-term stability of the hardness values, the standard block should be subjected to cryogenic treatment at temperatures between -20 ° C and -70 ° C and over six months

After the aging and then calibration.