At Fraunhofer LBF the measurements of the compression set can be performed at different testing temperatures for standardized testing methods (e.g. DIN ISO 815) of elastomer materials. For this, elastomers are pressed between standardized steel plates (see image above) and stored in a furnace. The compression set is calculated by measuring the thickness of the elastomer sample before and after storage. It provides information on the resilience of elastomers after long thermal strains and is of importance for the assessment of rubber gaskets, for instance.
As an example, the figure below shows the compression set of a soot filled elastomer at an aging temperature of 110 °C. The aging took place under normal air atmosphere as well as nitrogen atmosphere. The compression set increases faster during aging under air atmosphere than under nitrogen atmosphere.