Designing a New Dynamic Mechanical Analysis (DMA) System for Testing Viscoelastic Materials at High Frequencies

The aim of this study is to design a new dynamic mechanical analysis (DMA) measurement system that can operate for shear tests at frequencies as high as 10 kHz with strain amplitudes sufficient for viscoelastic materials operating in high-frequency deformation applications, such as tire rubbers. The available DMA systems in market cannot effectively operate for accurate and direct measurement of viscoelastic material properties for applications dealing with high-frequency deformation of materials. Due to this, the available DMA systems are used for indirect measurements at low frequencies and low temperatures, followed by using time-temperature superposition principle to predict the properties at high frequencies. The goal of this study is to make the range of the test broad enough to eliminate the use of the time-temperature superposition principle in the determination of properties of viscoelastic materials. Direct measurement of viscoelastic material properties and increasing the accuracy of results are the main motivations to design a new DMA system. For this purpose, the state-of-the-art technologies to achieve high frequencies and strain amplitudes as well as instrumentation and control of the system are studied. The design process is presented in this paper.

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Univariate and Multivariate Gauge Repeatability and Reproducibility Analysis on the High Frequency Dynamic Mechanical Analysis (DMA) Measurement System

Volume 2B: Advanced Manufacturing ◽

10.1115/imece2019-10986 ◽

2019 ◽

Author(s):

Roja Esmaeeli ◽

Haniph Aliniagerdroudbari ◽

Seyed Reza Hashemi ◽

Hammad Al-Shammari ◽

Muapper Alhadri ◽

...

Keyword(s):

Mechanical Properties ◽

Dynamic Mechanical Analysis ◽

Analysis Of Variance ◽

Measurement System ◽

High Frequency ◽

Mechanical Analysis ◽

Viscoelastic Materials ◽

High Frequencies ◽

Dynamic Mechanical ◽

Repeatability And Reproducibility

Abstract The quality of the collected data from a measurement system affects eventual decision making process. Therefore, the reliability of any measurement system is an important factor to be studied. Gauge repeatability and reproducibility (Gauge R&R) is the standard method to evaluate the measurement system and assess the adequacy of variation in the measurement data. Gauge R&R is a statistical tool which evaluates two main characteristics of the measurement system: repeatability and reproducibility. The Dynamic Mechanical Analysis (DMA) is a common measurement system for studying the dynamic mechanical properties of viscoelastic materials such as polymers. The newly developed High Frequency Dynamic Mechanical Analysis (HFDMA) is able to directly run the simple shear test at high frequencies without changing the specimen temperature. The complex shear modulus and damping factor of the viscoelastic materials are reported by the HFDMA system. In this study the uni-variable Gauge R&R study based on Analysis of Variance (ANOVA) is done on each measured characteristic of the HFDMA measurement system. The source of variations for each characteristic is distinguished. Then the multivariate Gauge R&R based on the Multivariate Analysis of Variance (MANOVA) is done and the percentage of multivariate Gauge R&R for the measurement with the multiple variables is reported. The results indicate that the HFDMA measurements are both repeatable and reproducible. Thus, the new HFDMA can be used as a measurement system to measure the mechanical properties of viscoelastic materials at high frequencies.

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Linear viscoelasticity of an acrylate IPN, analysis and micromechanics modeling

Soft Matter ◽

10.1039/d1sm00808k ◽

2021 ◽

Author(s):

Julie Diani ◽

Eleonore Strauch-hausser

Keyword(s):

Linear Viscoelasticity ◽

Superposition Principle ◽

Polymer Network ◽

Mechanical Analysis ◽

Frequency Sweep ◽

Temperature Superposition ◽

Time Temperature Superposition ◽

Time Temperature Superposition Principle ◽

Micromechanics Modeling ◽

Made In

An amorphous acrylate interpenetrated polymer network (IPN) was made in lab and tested by dynamic mechanical analysis. Using frequency sweep tests, it was shown that the time-temperature superposition principle applies...

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Integration of Atomistic Simulation with Experiment Using Time−Temperature Superposition for a Cross-Linked Epoxy Network

10.26434/chemrxiv.8326172 ◽

2019 ◽

Author(s):

Ketan Khare ◽

Frederick R. Phelan Jr.

Keyword(s):

Master Curve ◽

Glassy State ◽

Superposition Principle ◽

Quantitative Comparison ◽

Time Shift ◽

Data Sets ◽

Epoxy Network ◽

Temperature Superposition ◽

Time Temperature Superposition ◽

Time Temperature Superposition Principle

<a></a><a>Quantitative comparison of atomistic simulations with experiment for glass-forming materials is made difficult by the vast mismatch between computationally and experimentally accessible timescales. Recently, we presented results for an epoxy network showing that the computation of specific volume vs. temperature as a function of cooling rate in conjunction with the time–temperature superposition principle (TTSP) enables direct quantitative comparison of simulation with experiment. Here, we follow-up and present results for the translational dynamics of the same material over a temperature range from the rubbery to the glassy state. Using TTSP, we obtain results for translational dynamics out to 10<sup>9</sup> s in TTSP reduced time – a macroscopic timescale. Further, we show that the mean squared displacement (MSD) trends of the network atoms can be collapsed onto a master curve at a reference temperature. The computational master curve is compared with the experimental master curve of the creep compliance for the same network using literature data. We find that the temporal features of the two data sets can be quantitatively compared providing an integrated view relating molecular level dynamics to the macroscopic thermophysical measurement. The time-shift factors needed for the superposition also show excellent agreement with experiment further establishing the veracity of the approach</a>.

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