Viscoelasticity

Illustrated explanation

Compare set, relaxation, creep and viscoelastic response

4Viscoelasticity
Compare set, relaxation, creep and viscoelastic responseCallout 1: Compression set. Callout 2: Stress relaxation. Callout 3: Creep. Callout 4: Viscoelastic recovery. The controlled condition determines what is measured. Compression set is assessed after release; relaxation holds deformation; creep holds load; viscoelasticity includes time-dependent recovery. Current term: Viscoelasticity, callout 4. 1FreeHeldReleasedCompression set 2TimeForceFixed deformationStress relaxation 3TimeDeformationFixed loadCreep 4TimeDeformationLoad, hold, releaseViscoelastic recovery
  1. Compression set

    After the load is released and the specified recovery period passes, remaining deformation is the set. It is not retained sealing force.

  2. Stress relaxation

    At constant deformation, the measured force decreases over time. Compare tests with the same specimen and exposure conditions.

  3. Creep

    With a sustained load, deformation can grow over time. The loading condition differs from a relaxation test.

  4. ViscoelasticityThis term

    The response combines elasticity and time dependence. Recovery rate and loading history matter for polymers and elastomers.

The controlled condition determines what is measured. Compression set is assessed after release; relaxation holds deformation; creep holds load; viscoelasticity includes time-dependent recovery.

Qualitative curves and sections without measured values or predictions. Test temperature, specimen, exposure and timing must be equivalent before comparing materials.