Measuring of the Retention of Sealing Force
The test for stress relaxation in compression compared to the compression set test does not assess the recovery behaviour after relaxation but the retention of sealing force at constant deformation. Instrument-based it is considerably more complex to conduct than a compression set test and is less suitable for finished part tests.
Standard: ISO 3384
The advantage is the continual assessment of material behaviour under the influence of temperature. With the gained results existing calculation models for the representation of the relaxation behaviour can be checked. Moreover the performance potential of sealing materials can be shown.