Dynamic Mechanical Spectroscopy is an offresonance method working with forced oscillations. The specimens to be tested are first given a static load. Then sinusoidal mechanical excitations in a frequency range of 0.01 Hz to 100 Hz are superimposed.
In the case of pure elastic materials (e.g. stainless steel spring), the sample response to a constant dynamic deformation is always in phase δ = 0°) with the external excitation. Viscous materials show a time-delayed response to an external excitation.
In this case a phase shift of 90° can be observed (δ = 90°). Most materials demonstrate a mixture of elastic and viscous behaviour. Consequently the phase shift between sample excitation and response is of great interest.
Areas of application are dynamic mechanical thermal analysis as well as dynamic material testing.
Further fields of application are:
- Dynamic component testing
- Analysis of viscoelastic material properties
- Dynamic fatigue testing
- Relaxation and retardation (creep testing)
Predictive testing - according to a study of BAYER AG in Leverkusen/Germany
The development of new tires with improved properties (e.g. optimised rolling resistance) is a main target of the research departments in the tire industry. The test result will indicate the uniformly energy loss within the tire. The test procedure is able to simulate the energy loss determined with the drum test with a specially designed pulse repetition sample test mode, using the dynamic testing equipment EPLEXOR®. Above test can be carried out by using only the compound. At this early state the manufacture of a prototype is not necessary.
|Temperature:||-150 to 500 °C|
|Frequency range||0,01 Hz - 100 Hz|
|Force transducer:||150N, 2500N|
|Amplitude:||up to +/- 5mm|
|static strain:||up to 35mm|
|samples holder:||tension, compression, double shear, flexometer|