DMS

Categories

DMS
Dynamic Mechanical Spectrometer

The Dynamic Mechanical Analyzer measures the viscoelastic properties of a sample as a function of frequency, time temperature, stress, strain and the environment.
All parameters are chosen by the user to provide the desired information of the molecular structure of the specimen.
The combined benenfits of the spring support system, high resolution LVDT, heavy-duty stiffness of the instrument and the force range of up to 18 N will provide accurate information on very thin films as well as on stiff, thick, reinforced polymers. Different deformation modes allow measurements in the range from 103 to 1012 Pa.

Synthetic Oscillation Mode
In this mode multiples of the basic frequency are overlaid and the results calculated using the Fourier transformation. The advantages are evident. Samples can be measured at up to five frequencies at high data collecting rates with higher heating rates. This technique allows the frequency multiplexing even on samples which undergo drastic softening in a very narrow temperature range.

Fourier Transform (FT)
The EXSTAR DMS uses the Fourier Transform approach to analyze the strain signal with the highest possible resolution. This allows precise phase angle measurements at low levels with very small deformation amplitudes. This greatly enhances the measurement range for stiff and very soft samples all with one instrument.

Thermal Expansion Correction Function

During measurements in the wide temperature range (-150 to 600°C) samples undergo thermal expansion, shrinkage and creep. The highly accurate step motor automatically compensates the dimensional changes and makes sure the applied force is always the desired one, pre-tension is correct and the LVDT stays in its measurement range. This patented technique (USA Patents 4967601, 5046367, 5154085, 5182950) guarantees highly accurate and reliable data.

Wide Measurement Range

All deformation modes are available including dual and single cantilever bending, shear and film shear, three point bending for stiff samples and tension for thin film and single fibres with diameters down to a couple of µm. The sophisticated auto tension mode reduces the pretension during softening.

Advanced DMS Software

The advanced software package includes geometry depending subtraction, generation of master curves and calculation of activation energy as standard.
The unique Test Mode function makes it easy for the operator to determine the best suited sample geometry and to choose the best deformation mode for his sample.

Multiple Deformation Modes

As standard the DMS 6000 comes with the 20 mm dual cantilever bending and the tension head. To be able to measure samples with different characteristics a variety of optional heads are available. This ranges from dual and single cantilever with different active lengths, 3 point bending, shear and film shear, to tension and compression. This allows characterization of all sample shapes from single fibres to stiff bulk samples.

Download PDF completo