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Hardness determination - Shore D

What is it?

Shore hardness is a test that evaluate the surface hardness of polymers or elastomers. However, Shore hardness is not reflected in other properties as is the case of other types of hardness and therefore cannot be used as a mean to predict wear resistance or other mechanical properties.
The Shore hardness evaluates the indentation resistance, which varies with time, mainly because the materials used in this type of test have high resilience and therefore a great capacity to absorb energy and to adapt to the deformation.

What is it used for?

Shore D hardness is suitable for measuring the hardness of synthetic materials, rigid plastics, synthetic resin, among others.

Equipment and working conditions

A CV Instruments Limited equipment, is used to determine Shore D hardness.
In this test, the durometer measures the resistance to penetration through an indenter to which a force, perpendicular to the surface of a material, is applied. A reading system converts the vertical displacement of the penetrator to a Shore hardness value on a suitable scale ranging from 0 to 100 Shore.
To carry out this test, the samples shall have the surface as flat as possible and a thickness of at least 6 mm. For each sample, five indentations are performed, which must be performed at least 12 mm from the sample edge and at least 6 mm apart between each analysis point.

Example of use

Automotive industry - Evaluation of polymer hardness to predict impact absorption behavior, resistance to scratch, resistance to mechanical surface stress.