The surface of the

Another requirement for sample size is sufficient area so that the position of the shore A and D durometers should be at least 12mm from any edge, at least 15mm for THE AO and at least 4.5mm for the AM.

The surface of the sample should be flat in a certain range, parallel up and down, so that the pressure foot can contact with the sample in a sufficient area. The radius of contact surface of Shaw type A and D hardness tester should be at least 6mm, AO type should be at least 9mm, and AM type should be at least 2.5mm.

Shore hardness tester generally cannot obtain satisfactory results on curved, uneven and rough surfaces. However, they also have special applications, such as ISO7267-2 for apparent hardness measurement of rubber covered rubber rollers. There should be a clear understanding of the limitations of these particular applications.

The thickness of the sample should be at least 6mm when hardness is determined by using A chromatograph Shaw type A, D and AO hardness tester.

When using a Shore AM hardness tester, the sample thickness should be at least 1.5mm.

For thin sections with thickness less than 6mm and 1.5mm, the sample can be composed of no more than 3 layers in order to obtain sufficient thickness. For Shaw TYPE A, D, and AO hardness tester, the total thickness of the sample after stacking shall be at least 6mm, and for AM type, the total thickness of the sample after stacking shall be at least 1.5mm. However, the results of the laminated sample and the single-layer sample are not necessarily the same.

Samples should be similar for comparison purposes.