TA Instruments RSA-G2, Руководство пользователя

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DYN AMIC MECHANICAL AN ALYSIS I TESTING MODES & APPLICATIONS
Temperature Sweeps
In this test, a step and hold temperature profile is applied. At each temperature step.
the sample is held at temperature for a defined amount of time to ensure temperature
uniformity in the material. The material response is then measured at one or multiple
frequencies at a strain within the LVR.
The top figure shows results of a temperature sweep on a pressure sensitive adhesive
over a temperature range of 40°C to 80 °e. At each 10°C step in the sweep. the sample
was scanned over a frequency range of 0.1 to 100 Hz. The storage modulus is plotted
as a function of frequency for each 10 °C step. This is the method of choice for Time­
Temperature Superposition studies as all the frequency-dependent data are collected at
the same temperature.
Soak
lime ,
Oscillatory
Measurement
Time
Time-temperature superposition (TIS) is used to extend the frequency range by running a
series of frequency sweeps over a wide range of temperatures. The bottom figure shows a
master curve constructed at a reference temperature of 25 °e for a sample of Acrylonitrile­
butydiene-styrene (ABS).ln this example the original frequency range of two decades was
extended to 14 decades.
Testing Modes and Applications
20
103
Temperature/Frequency Sweep on PSA
Temperature Range: 40°C to 80 °e
Temperature Step: lOoe
Shear Sandwich
10-1
100 101
Frequency
(Hz)
TIS on ABS at a Reference Temperature of
25°C
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1011
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Extended Sweep
ITS
Extended
Range
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Range Range
102
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108
10-3 10-1
101
103
105 107
Frequency
(Hz)
1011
10-1
10-2