DYNAMIC MECHANICAL ANALYSIS

The UD series was developed to meet the requirements of dynamic applications even in cyclic applications with a high number of cycles and a short stroke. The actuators are designed to operate either alone on structures or on production lines for quality control. Not just simple electrodynamic actuators, but true electrical machines for any type of application where high performance is required.

Brochure

DMA TEST SYSTEMS

Dynamic mechanical analysis (DMA) is a widely used technique to characterize the properties of a material as a function of temperature, time, frequency, stress, atmosphere, or a combination of these parameters.
By applying a small deformation to a sample in a cyclic manner, it is possible to study the material’s response to stress, temperature, frequency, and other values. The sample can be subjected to controlled stress or controlled strain. In DMA, the viscoelastic property of the material is studied by applying a sinusoidal force (stress σ) and measuring the resulting displacement. For a perfectly elastic solid, the resulting strain and stress will be perfectly in phase.

For a purely viscous fluid, there will be a 90-degree phase shift of the deformation to the stress. Viscoelastic
Viscoelastic polymers have intermediate characteristics for which some phase shifts will occur during DMA testing.

Typical challenges in DMA testing are:

The difficulty of accurately measuring movement and force at high frequencies.
The ability to accurately measure the phase lag between the applied displacement and the resultant force.
Frequency variations in excitation, stress, strain and temperature.
Ensure correct PID tuning and control stability and accuracy even though sample behaviour may sometimes change by orders of magnitude during testing
Combine and synchronise mechanical and temperature excitations to the specimen ensuring that the specimen temperature is uniform.

Actuators for DMA tests