Identity Tests
Of component and material
Significance and Test Method
Is the component delivered or used equal to the product that has been sampled and delivered ever since? Just visually, it is not possible to identify a material type. For an identity test, simple testing methods quickly provide information about the product in question.
Identity tests are therefore tests that show, within a defined scope, a match or deviation of an inspection lot with reference values from the sampling or previous deliveries. Such tests serve as incoming goods inspections or as part of a damage analysis in order to classify parts quickly and with reasonable effort.
The Basis of Identity Tests
As part of an identity test, we determine the component dimensions as well as its hardness and density. All values are compared with the specifications from the sampling, applicable specification or agreement.
Density is a material constant that is independent of the dimensions of the test specimen. The density measurement is one of the simplest and quickest tests to perform and often provides information about changes in the elastomer compound.
Hardness – being relatively easy to measure – is one of the most popular and widely used identity testing methods in the elastomer industry. Although it appears to be a meaningful test method at first glance, it should be used with caution. There are many influencing variables that can affect the determined hardness value and lead to an incorrect result in the good/bad evaluation of the component.
If deviations are found in one of these three identity tests, further tests are recommended.
Downloads
You can find more information about identity verification of elastomer parts in our technical reports.
Identity verification for elastomers - hardness and density
Within the scope of an identity verification, certain material properties are examined on components of a test lot and checked for conformity with the reference values from the sampling. On elastomer components, the density and hardness of the component material are usually determined in addition to the dimensions.
Hardness Test
In the report you will find answers to the following questions: How and with which methods is the hardness tested on elastomer components? Can the results of hardness measurements be compared or converted to other testing methods? Which conclusions can be drawn from the hardness test regarding the quality of a material or component?
