TA Instruments invites you to experience the in Dynamic Mechanical Analyzers, the Discovery DMA 850. Building on technologies of the selling DMA, improvements in every aspect of DMA performance deliver the accurate and reproducible measurement of mechanical properties over a wide temperature range. It’s never been easier to get DMA data!
Stiff, Frictionless Air Bearing Support
The non-contact drive motor transmits force directly to a rectangular air bearing slide. The slide is guided by eight porous carbon air bearings. Pressurized gas forms a frictionless surface that permits the slide to “float.” The slide connects directly to the drive shaft and sample clamp for 25 mm of frictionless displacement. The rectangular shape of the drive shaft completely eliminates off-axis motion.
Wide Range, High Resolution Optical Encoder
Based on diffraction patterns of light through gratings, optical encoders provide resolution over very wide ranges compared to LVDT’s used in competitive devices. Due to the 0.1 nanometer resolution of the optical encoder, very small amplitudes can be measured. Enhanced optical encoder sensitivity, combined with refined motor controls, results in displacements up to 100× smaller than previous drive technology, including control of displacements as small as 5 nm.
Responsive Direct Drive Motor
The DMA 850’s non-contact motor applies both dynamic and static deformation over the full 25 mm range of motion, providing control in all modes and clamp positions.The motor is constructed of high-performance lightweight composites that axial and torsional stiffness while system inertia.Sophisticated control electronics enable the fast motor control over the wide continuous range of force, from 0.1 mN to 18 N. This enables the system to capture a broad spectrum of material properties with the high level of sensitivity and accuracy. These precision controls also provide vast improvements in transient response, including a step-displacement response of 50 ms, as well as a 100× improvement in stress-control accuracy.
Optimized Mechanics
The critical drive components of the DMA 850 are mounted within a high-stiffness aluminum casting that is rigidly mounted to an FEA-optimized instrument frame. Competitive systems based on moveable, hanging, or soft-mounted frames are constrained in their effective frequency-range by the combination of sample stiffness and system resonance.
Temperature-Controlled Transducer
The transducer is temperature-controlled to eliminate drift associated with temperature changes from the sample or laboratory environment. The result is the stable platform for mechanical characterization of materials even under extreme conditions. The DMA 850 is thecommercial DMA instrument to feature a temperature-controlled force and displacement transducer.
Auto-Ranging
Because the modulus of a material can change by several orders of magnitude in a narrow range of time or temperature, the selection of programming parameters can make or break an experiment. If the deformation chosen is too large there could be excessive sample creep. If it is too small, force sensitivity suffers. The all new intelligent Auto-Ranging feature takes the guess work out of selection of starting conditions and ensures force and displacement are automatically maintained within reasonable user defined limits. Program the experiment and walk-away with the peace of mind that you will get great data the every time.
Direct Strain
Faster electronics, all new digital signal processor (DSP) controls, and an enhanced drive system allow for an all-new type of strain control in the DMA 850. DirectStrain is real-time strain control for faster and more accurate measurements of challenging samples and test conditions, such as rapidly changing materials or soft specimens at high frequencies. DirectStrain guarantees consistent data collection even during transitions on quickly changing samples and a 50× improvement in strain accuracy over conventional DMA technology.