Dynamic Mechanical Analysis


Significance and Test Method

Elastomers are viscoelastic materials and combine viscous and elastic properties. The dynamic mechanical properties of such materials are influenced, among other things, by the type and intensity of the load, the frequency of the load and the temperature of use.

In the dynamic-mechanical analysis DMA, sometimes also called dynamic-mechanical thermal analysis, DTMA, we qualitatively and quantitatively determine these dynamic-mechanical properties under various conditions.

Significance for Application Technology

By means of the DMA, it is possible to determine numerous material properties. The complex data and characteristic curves of the DMA are an important basis for FEA calculations that map the dynamic recovery behaviour of elastomeric components over an entire temperature range and under changing pressure. This is particularly helpful in order to assess the application limits of a seal at low temperatures.

The DMA Testing

The determination of dynamic mechanical properties of viscoelastic materials is defined in several standards. Among them are ISO 6721 and numerous ASTM standards, for example ASTM D 4065, ASTM D 4440 or ASTM D 5279.

In the Dynamic Mechanical Analysis we determine the following quantities quantitatively and qualitatively and as a function of temperature:

  • the visco-elastic behaviour or the damping properties (= tan delta) at different, defined deformations and frequencies
  • the loss or storage modulus of the materials at different, defined deformations and frequencies
  • the flow and relaxation behaviour of elastomers.

The test specimens undergo tensile, compressive or flexural loading while force, displacement, amplitudes, frequencies, dynamics or temperature are changed as required. The measured variables and parameters of DMA are extremely diverse and variable, making this analysis very flexible to use.

The tolerance ranges of all measured variables are very tight. The possible temperature of the measurements ranges from 100 °C to 600 °C.

Der untersuchte Standard FKM hat einen TR10 Wert von -16 C.

Almost none!

No standardised test specimens are necessary for a DMA. We can measure on almost all elastomer specimens, regardless of whether it is a finished part, a test plate or a damaged part. Only the compression or bending mode requires plane-parallel specimens, which we usually make from test plates or prefabricated parts. In tensile mode we use common, but slightly shortened, tensile specimens (e.g. S3, S3A…).

Der untersuchte Tieftemperatur FKM hat einen TR10 Wert von -30 °C.


More information on dynamic mechanical analysis DMA can be found in our examples and technical reports:

In this report, the authors Bernd Sprenger, Dipl.-Ing. Bernhard Richter and Dipl.-Ing. (FH) Ulrich Blobner present the three most important methods of physical analytics for elastomers. They explain the methods of thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA).