Evaluation of Microdamage, Healing, and Heat Dissipation of Asphalt Mixtures, Using a Dynamic Mechanical Analyzer

2001 ◽  
Vol 1767 (1) ◽  
pp. 60-66 ◽  
Author(s):  
Yong-Rak Kim ◽  
Dallas N. Little ◽  
Robert L. Lytton
Keyword(s):  
Heat Dissipation ◽  
Asphalt Mixtures ◽  
Dynamic Mechanical Analyzer ◽  
Dynamic Mechanical ◽  
Microdamage Healing

scholarly journals Multiscale Characterization of E-Glass/Epoxy Composite Exposed to Extreme Environmental Conditions

2021 ◽  
Vol 5 (3) ◽  
pp. 80
Author(s):  
George Youssef ◽  
Scott Newacheck ◽  
Nha Uyen Huynh ◽  
Carlos Gamez
Keyword(s):  
Power Distribution ◽  
Epoxy Composite ◽  
Fire Retardant ◽  
Sandwich Composite ◽  
Dynamic Mechanical Analyzer ◽  
Fire Event ◽  
Balsa Wood ◽  
X Ray ◽  
Dynamic Mechanical ◽  
Composite Skins

Fiber-reinforced polymer matrix composites continue to attract scientific and industrial interest since they offer superior strength-, stiffness-, and toughness-to-weight ratios. The research herein characterizes two sets of E-Glass/Epoxy composite skins: stressed and unstressed. The stressed samples were previously installed in an underground power distribution vault and were exposed to fire while the unstressed composite skins were newly fabricated and never-deployed samples. The mechanical, morphological, and elemental composition of the samples were methodically studied using a dynamic mechanical analyzer, a scanning electron microscope (SEM), and an x-ray diffractometer, respectively. Sandwich composite panels consisting of E-glass/Epoxy skin and balsa wood core were originally received, and the balsa wood was removed before any further investigations. Skin-only specimens with dimensions of ~12.5 mm wide, ~70 mm long, and ~6 mm thick were tested in a Dynamic Mechanical Analyzer in a dual-cantilever beam configuration at 5 Hz and 10 Hz from room temperature to 210 °C. Micrographic analysis using the SEM indicated a slight change in morphology due to the fire event but confirmed the effectiveness of the fire-retardant agents in quickly suppressing the fire. Accompanying Fourier transform infrared and energy dispersive X-ray spectroscopy studies corroborated the mechanical and morphological results. Finally, X-ray diffraction showed that the fire event consumed the surface level fire-retardant and the structural attributes of the E-Glass/Epoxy remained mainly intact. The results suggest the panels can continue field deployment, even after short fire incident.

Thermal characterization of carbon nanoparticle infused GFRP using dynamic mechanical analyzer

2019 ◽  
Vol 6 (10) ◽  
pp. 105317 ◽  
Author(s):  
R Karthicksundar ◽  
Balaji Rajendran ◽  
P K Dinesh Kumar ◽  
S Devaganesh
Keyword(s):  
Thermal Characterization ◽  
Dynamic Mechanical Analyzer ◽  
Carbon Nanoparticle ◽  
Dynamic Mechanical

Thermal Shrinkage Behavior of Battery Separator

2018 ◽  
Author(s):  
Shutian Yan ◽  
Jie Deng ◽  
Chulheung Bae ◽  
Xinran Xiao
Keyword(s):  
Thermal Expansion ◽  
Elevated Temperatures ◽  
Coefficient Of Thermal Expansion ◽  
Porous Membrane ◽  
Thermal Shrinkage ◽  
Dynamic Mechanical Analyzer ◽  
Free Standing ◽  
Dynamic Mechanical ◽  
Battery Separator ◽  
Shrinkage Behavior

Battery separators are thin, porous membrane of 20∼30 microns thickness. Polymer separators display a significant amount of shrinkage at elevated temperatures. It is difficult to quantitatively characterize the large shrinkage behavior with a free standing separator sample. This paper examines the use of a dynamic mechanical analyzer under tensile mode in measuring the coefficient of thermal expansion (CTE) of three commonly used separators.

Microstructures and Damping Capacity of Mg-6Zn-0.5Zr Alloy

2012 ◽  
Vol 557-559 ◽  
pp. 1624-1628 ◽  
Author(s):  
Xian Lan Liu ◽  
Chu Ming Liu ◽  
Wen Yu Zhang ◽  
Jian Hua Luo ◽  
Su Min Zeng
Keyword(s):  
Strain Amplitude ◽  
Critical Strain ◽  
Damping Capacity ◽  
Damping Properties ◽  
Dynamic Mechanical Analyzer ◽  
Dynamic Mechanical ◽  
Experimental Strain ◽  
Damping Peak ◽  
Peak Value

The dynamic mechanical analyzer (DMA) was applied to investigate the damping properties of Mg-6Zn-0.6Zr alloys. The results show that the as-cast Mg-6Zn-0.6Zr alloy exhibits higher strain amplitude independent damping performance than that of as-homogenized. The strain amplitude dependent damping of the as-homogenized has the best damping performance with the strain amplitude from 3×10-5 to 6×10-4, and the as-extruded is the lowest. When the strain amplitude exceeded 6×10-4, the as-extruded has the best damping capacity all the time within the experimental strain amplitude, and all the alloys reach the high damping capacity. Two critical strain amplitude points were detected in the alloy as-extruded and as-homogenized. The damping peak value is 0.0192 with the strain amplitude of 1.5×10-3 presented in the alloy as-extruded.

Dynamic Viscoelastic Properties of Rice Kernels Studied by Dynamic Mechanical Analyzer

2007 ◽  
Vol 3 (2) ◽  
Author(s):  
Ke-cheng Chen ◽  
Dong Li ◽  
Li-jun Wang ◽  
Necati Özkan ◽  
Xiao Dong Chen ◽  
...  
Keyword(s):  
Glass Transition ◽  
Viscoelastic Properties ◽  
Loss Modulus ◽  
Brown Rice ◽  
Aluminum Foil ◽  
Moisture Loss ◽  
Dynamic Mechanical Analyzer ◽  
Rice Varieties ◽  
Razor Blade ◽  
Dynamic Mechanical

Dynamic viscoelastic properties of brown rice kernels were investigated using a dynamic mechanical analyzer (DMA). In order to meet the sample requirements for the DMA and prevent moisture loss of rice kernels during the DMA measurements, necessary precautions were taken. To prevent moisture loss of rice kernels during the DMA measurements at temperatures ranging from room temperature to 120 degrees centigrade, rice kernels were wrapped with a thin layer of sealing film. Then the wrapped rice kernels were additionally covered with an aluminum foil. Two ends of the wrapped brown rice kernels were cut with a razor blade; subsequently both ends of the cut rice kernels were filed using fine sandpaper to produce near cylindrical rice kernels with parallel ends. The storage modulus of the rice kernels decreased with increasing temperature and moisture content. The loss modulus and the tan delta (loss factor) of the rice kernels as a function of temperature showed clear peaks, which are associated with the glass transition of rice kernels. Two rice varieties had been investigated, and the results showed that the dynamic viscoelastic properties of these rice samples were not significantly different. The glass transition temperatures for the long-grain rice kernels with the moisture contents of 17.4, 13.8, and 10.9 wt.% were determined as 45, 58, and 66 degrees centigrade, respectively.

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