Dynamic mechanical analysis(dma)

1. Dynamic mechanical analysis(DMA)

2. Introduction
DMA is an important technique used to
measure the mechanical and viscoelastic
properties of materials such as thermoplastics,
thermosets, elastomers, ceramics and metals.
In DMA, the sample is subjected to a periodic
stress in one of several different modes of
deformation (bending, tension, shear and
compression).
Modulus as a function of time or temperature
is measured and provides information on phase
transitions.

3. Natural
viscoelastic

4. Dynamic mechanical analysis(DMA) measures the mechanical
properties of viscoelastic materials as a function of temperature
of frequency when the materials are deformed under the action
of a periodic force or displacement
The wing of an air plane undergoing a quality test.
Most modern constructional component are in fact subject to a
wide rang of stresses at different frequencies.

5. The idealized DMA
curve such as we
would be obtained
from the
measurement of an
amorphous thermal
plastic polymer
The elastic modulus
is measured by
pascal, megapascal,
or gigapascal

6. The concept of storage
and loss modulus can be
illustrated by considering
what happens when a
tennis ball bounces on the
ground.
On impact the ball
undergoes deformation,
and does not bounds back
up to the height which it
was dropped

7. DMA: MCR
702
MultiDrive

8. Schematic
diagrams of
the different
DMA
measurement
mode.
The mode is
determined
by the shape
and nature
and the
information
required .

9. • The DMA can be either stress or strain
controlled: strain- controlled analyzers move
the probe a certain distance and measure the
stress applied; strain-controlled analyzers
provide a constant deformation of the
sample.
• DMA analyzers can also apply stress or strain
in two manners
• axial and torsional deformation applies a
linear force to the sample and is typically
used for solid and semisolid materials to test
flex, tensile strength, and compression. Axial
instrument should not be used for fluid
samples with viscosities below 500 Pa-s.

10. Torsional analyzer applies
force in a twisting motion;
this type of analysis is used
for liquids and polymer
melts but can also be
applied to solids. Torsional
analyzers cannot handle
materials with high
modulus

11. DMA
measurement
can be
performed as
a function of
Different applications associated with each
parameter

12. This diagram shows
the temperature scan
of a polylactide or
PLA .
The sample was
measured in the
tension mode .
So we used young's
module E

13. Measurements at low
frequencies can be
quit time-consuming.
Besides this, at the
end of the scale, very
high frequencies
can’t be directly
measured.
So the question .
What is the solution?

14. Master curve construction
The aim is to be able to make
production in frequency ranges
that are not readily accessible to
direct measurement. One makes
use of the fact that at high
frequencies, a material behaves
the same as at low temperatures .
This is known as the time
temperature superposition
principle or TTS .

15. Master curve construction
The aim is to be able to make
production in frequency
ranges that are not readily
accessible to direct
measurement. One makes
use of the fact that at high
frequencies, a material
behaves the same as at low
temperatures .
This is known as the time
temperature superposition
principle or TTS .
Master curve can be quickly
constructed using the DMA, due
to the excellent temperature
stability and accuracy of the
instrument, as well as the high
frequencies that can be reached.
This allows information to be
gained about the dynamic
behavior and the molecular
structure and cross-linking of
materials

16. As summary
Why we use
DMA?

18. Advantages and Disadvantages of Dynamic Mechanical Analysis
Advantages Disadvantages
Accurate Analysis Results Difficult to Track Back the Actual
Problems
Identifies Problem in the
Runtime
Very Difficult Task for Developers
May Find Problems that Static
Analysis Can’t Find
May Provide a False Sense of
Security that Everything is Being
Addressed
Validation of Static Code Analysis
Findings
Analysis is Only as Good as the
Tests you Write and implement

19.  Measurement of the glass
transition temperature of
polymers
 Varying the composition of
monomers
 Effectively evaluate the
miscibility of polymers
 To characterize the glass
transition temperature of a
material

20. Prepared by :
Manar Abduljabbar Humadi &
Murtada Hamid