DMA Test

1Specimen

Bar

Fiber volume fraction %

Span mm

Width mm

Thickness mm

Clamp

Three-point bending

2Test

Hold a fixed strain for a few minutes at each temperature, then step the temperature up and repeat.

Strain %

Hold per step min

From °C

To °C

Step °C

Reference °C

Temperature °C

Stress MPa

Load for min

Then unload for min

Temperatures °C

From Hz

To Hz

From °C

To °C

Frequencies

0.1 Hz 1 Hz 10 Hz

3About the modelEquations and sources

Dynamic mechanical analysis

How stiffness depends on time and temperature

A polymer is not simply elastic: under a fixed strain its stress slowly relaxes, and under a fixed load it slowly creeps. A DMA bends a small bar, here in three-point bending, and measures this behavior while it controls the temperature. Near the glass transition the resin changes from glassy to rubbery and its stiffness drops by about a hundred times.

Four tests show the same material from different sides: stress relaxation, creep and recovery, a frequency sweep and a temperature ramp. All four come from one model of fully cured 3501-6 epoxy.

Choose a bar and a test, then select Run DMA test.

How stiffness depends on time and temperature

Readings

What to notice