Rigid cross-linked PVC foams with high shear properties: The relationship between mechanical properties and chemical structure of the matrix

2014 ◽  
Vol 97 ◽  
pp. 74-80 ◽  
Author(s):  
Zhiwei Jiang ◽  
Kun Yao ◽  
Zhonghui Du ◽  
Jian Xue ◽  
Tao Tang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Chemical Structure ◽  
High Shear ◽  
Shear Properties ◽  
The Matrix ◽  
The Relationship

scholarly journals Study on σ Phase in Fe–Al–Cr Alloys

Metals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 1092 ◽  
Author(s):  
Jintao Wang ◽  
Shouping Liu ◽  
Xiaoyu Han
Keyword(s):  
Mechanical Properties ◽  
Grain Boundaries ◽  
Grain Growth ◽  
Thermodynamic Calculation ◽  
Second Phase ◽  
Σ Phase ◽  
Austenitic Transformation ◽  
The Matrix ◽  
The Relationship

In this paper, a method of using the second phase to control the grain growth in Fe–Al–Cr alloys was proposed, in order to obtain better mechanical properties. In Fe–Al–Cr alloys, austenitic transformation occurs by adding austenitizing elements, leading to the formation of the second phase and segregation at the grain boundaries, which hinders grain growth. FeCr(σ) phase was obtained in the Fe–Al–Cr alloys, which had grains of several microns and was coherent and coplanar with the matrix (Fe2AlCr). The nucleation of σ phase in Fe–Al–Cr alloy was controlled by the ratio of nickel to chromium. When the Ni/Cr (eq) ratio of alloys was more than 0.19, σ phase could nucleate in Fe–Al–Cr alloy. The relationship between austenitizing and nucleation of FeCr(σ) phase was given by thermodynamic calculation.

Comparison of Shear, Compressive and Tensile Characteristics of Cast Irons

1973 ◽  
Vol 15 (1) ◽  
pp. 53-60 ◽  
Author(s):  
R. D. Adams ◽  
M. A. O. Fox
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Design Criteria ◽  
Matrix Structure ◽  
Proof Stress ◽  
Cast Irons ◽  
The Matrix ◽  
The Relationship ◽  
Graphite Inclusions ◽  
Strength And Ductility

Cast irons were produced with variations in the quantity and shape of the free graphite inclusions and in the matrix structure to investigate the relationship between the shear, compressive and tensile mechanical properties. Differences were observed which may have a significant effect on design criteria for cast irons. For example, the ratio of shear to tensile strengths decreased from about 1·25 to 0·577 and the ratio of 0·1 per cent proof stress in compression to that in tension decreased from approximately 2 to 11 as the tensile strength (and ductility) were increased.

scholarly journals Investigation of Mechanical Properties of Low-Density Polyethylene with Copper Nanoparticles

2021 ◽  
Vol 15 ◽  
pp. 181-188
Author(s):  
M. V. Klychnikova ◽  
Kyaw Ye Ko
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Filler Content ◽  
Physical And Mechanical Properties ◽  
Ex Situ ◽  
Flow State ◽  
In Situ Preparation ◽  
The Matrix ◽  
The Relationship

In this work, it is shown that the method of the in situ preparation of Cu/LLDPE by combining the formation of a composite and a nanodispersed phase in the viscous-flow state of a polymer makes it possible to achieve a uniform distribution of nanoparticles in the matrix and effectively regulate their mechanical and functional properties. The optimal concentration of Cu nanofiller was found to be 2-5%, allowing to achieve the best mechanical properties. Comparative analysis of the physical and mechanical properties of Cu/LLDPE nanocomposites obtained by various methods shows that the deformation and strength characteristics of the 3CuLLDPE nanocomposite obtained by the in situ method are improved in comparison with the properties of the 3CuLLDPE nanocomposite, prepared by ex situ method. The relationship between the filler content and the modulus of elasticity/tensile strength has been determined. With an increase in the filler content, the elastic modulus increases by 10-20%, and the tensile strength decreases by 30%. Elongation at break for samples with nanofiller content up to 3 wt. % higher than unfilled polymer

Rheology, Mechanical Performance and Penetrability through Flax Nonwoven Fabrics of Lime Pastes

2022 ◽  
Author(s):  
Ali Rakhsh Mahpour ◽  
Monica Ardanuy ◽  
Heura Ventura ◽  
Joan Ramon Rosell ◽  
Josep Claramunt
Keyword(s):  
Mechanical Properties ◽  
Mechanical Performance ◽  
Construction Materials ◽  
Short Fibers ◽  
Plant Fibers ◽  
Nonwoven Fabrics ◽  
The Matrix ◽  
Negative Effect ◽  
Long Fibers ◽  
The Relationship

The use of plant fibers as a reinforcement for fragile matrices could be an option to improve the sustainability of the construction materials. These reinforcements can be in different forms as short fibers, long fibers or woven or nonwoven fabrics. The mechanical performance of the composites is significantly related to the adhesion between the matrix and the fibers. In the case of nonwoven reinforcement, to get good adhesion, the penetration of the paste is a key point. That is why this study addresses the relationship between rheology, penetration through the nonwoven fabrics and the mechanical properties of various lime pastes with different contents of water and metakaolin (MK). The effect of the binder’s grinding is also evaluated. The results indicate that MK pastes with higher w/b ratios penetrate better into nonwovens, Grinding has a negative effect on penetrability despite improving the mechanical properties of the pastes.

scholarly journals Effect of Polypyrrole on the Electrical, Dielectric and Mechanical Properties of Waterborne Epoxy Coatings

2020 ◽  
Vol 30 (1) ◽  
pp. 11
Author(s):  
Thu Thuy Thai ◽  
Thuy Duong Nguyen ◽  
Thi Thu Trang Nguyen ◽  
Gia Vu Pham ◽  
Dai Lam Tran ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Chemical Structure ◽  
Volume Resistivity ◽  
Chemical Oxidation ◽  
Epoxy System ◽  
Conducting Composite ◽  
Chemical Oxidation Polymerization ◽  
Waterborne Epoxy ◽  
The Matrix ◽  
Dielectric And Mechanical Properties

In this context, conducting composite based on waterborne epoxy system and polypyrrole (PPy) was investigated. The polypyrrole was synthesized by chemical oxidation polymerization. Its morphology and chemical structure were confirmed by using field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR). Then, PPy was well-dispersed in the epoxy coating and had a good compatibility with the matrix. The effects of PPy on dielectric, electrical and mechanical properties of epoxy/PPy composites was examined. The dielectric constant and electrical conductivity of the coatings increased with addition of PPy fillers. Over to 15 wt. % of PPy loading, the volume resistivity of samples slightly decreased from 6.7 × 1010 to 1.5 × 1010 Ω cm. In contrast, the presence of PPy diminished both impact and abrasion resistance of the epoxy/PPy composites, down to 160 kg cm and 10.2 L/mil, respectively, but they stayed acceptable for the coatings. The results reveal that the epoxy containing polypyrrole is suitable for various electrical and dielectric applications.

scholarly journals Finding Minimal Optimal Indent Separation for Polystyrene via Instrumental Nanoindentation and FEA Method

2020 ◽  
Vol 10 (12) ◽  
pp. 4262
Author(s):  
Chulin Jiang ◽  
Michael Davis ◽  
Jurgita Zekonyte
Keyword(s):  
Mechanical Properties ◽  
Indentation Depth ◽  
Optimal Separation ◽  
Maximum Indentation Depth ◽  
Submicron Scale ◽  
The Matrix ◽  
Different Depths ◽  
Set Up ◽  
The Relationship ◽  
Non Destructive

Nanoindentation became a standard non-destructive technique to measure mechanical properties at the submicron scale of various materials. A set of empirical rules were established to guarantee the validity of the results. One of those rules is the separation between individual indents that should be 20–30 times maximum indentation depth. This paper investigates the influence of the distance between indents on the accuracy of mechanical properties for polystyrene with a view to determine minimum optimal separation that is needed to measure various material properties. A series of different depths with three different orientations was considered through both the experimental and finite element method to explore the relationship between the distance and indentation depth. Both methods demonstrated that hardness and modulus values for polystyrene keep stable with the distance approximately 15 times the maximum indentation depth for the matrix type set up, and nominal separation of 10 is enough when indents are executed in a single row or column.

Sunlight exposure: the effects on the performance of paragliding fabric

2018 ◽  
Vol 69 (05) ◽  
pp. 381-389
Author(s):  
MENGÜÇ GAMZE SÜPÜREN ◽  
TEMEL EMRAH ◽  
BOZDOĞAN FARUK
Keyword(s):  
Mechanical Properties ◽  
Aging Process ◽  
Air Permeability ◽  
Sunlight Exposure ◽  
Test Results ◽  
Coating Materials ◽  
Strength Tests ◽  
Before And After ◽  
The Relationship ◽  
Dark Blue

This study was designed to explore the relationship between sunlight exposure and the mechanical properties of paragliding fabrics which have different colors, densities, yarn counts, and coating materials. This study exposed 5 different colors of paragliding fabrics (red, turquoise, dark blue, orange, and white) to intense sunlight for 150 hours during the summer from 9:00 a.m. to 3:00 p.m. for 5 days a week for 5 weeks. Before and after the UV radiation aging process, the air permeability, tensile strength, tear strength, and bursting strength tests were performed. Test results were also evaluated using statistical methods. According to the results, the fading of the turquoise fabric was found to be the highest among the studied fabrics. It was determined that there is a significant decrease in the mechanical properties of the fabrics after sunlight exposure. After aging, the fabrics become considerably weaker in the case of mechanical properties due to the degradation in both the dyestuff and macromolecular structure of the fiber

Morphology and Mechanical Properties of Polyethylene Terephthalate/Ethylene Propylene Diene Monomer (PET/EPDM) in the Presence of Nanoclay

2020 ◽  
Vol 57 (3) ◽  
pp. 249-259
Author(s):  
Baifen Liu ◽  
Mohammad Mirjalili ◽  
Peiman Valipour ◽  
Sajad Porzal ◽  
shirin Nourbakhsh
Keyword(s):  
Mechanical Properties ◽  
Impact Strength ◽  
Thermal Destruction ◽  
Processing Temperature ◽  
Tem Analysis ◽  
Maximum Stiffness ◽  
Cloisite 30B ◽  
Nano Clay ◽  
The Matrix ◽  
Sample Maximum

This research deals with the mechanical properties, microstructure, and interrelations of triple nanocomposite based on PET/EPDM/Nanoclay. These properties were examined in different percentages of PET/EPDM blend with compatibilizer (Styrene-Ethylene/Butylene-Styrene)-G-(Maleic anhydrate) (SEBS-g-MAH). Results showed that the addition of 15% SEBS-g-MAH improved the toughness and impact strength of this nanocomposite. SEM micrographs indicated the most stable fuzzy microstructure in a 50/50 mixture of scattered phases of EPDM/SEBS-g-MAH. The effects of percentages of 1, 3, 5, 7 nanoclay Cloisite 30B (C30B) on the improvement of the properties were evaluated. With the addition of nano clay, the toughness and impact strength was reduced. Thermal destruction of nanoclay in processing temperature led to the decreasing dispersion of clay plates in the matrix and a reduction in the distances of nano clay plates in the composite compared to pure nano clay. XRD and TEM analysis was used to demonstrate the results. By adding 1% of nanoclay to the optimal sample, maximum stiffness, and Impact strength, among other nanocomposites, was achieved.

Soil and Stream Water Chemistry During Spring Snowmelt

1992 ◽  
Vol 23 (1) ◽  
pp. 13-26 ◽  
Author(s):  
W. H. Hendershot ◽  
L. Mendes ◽  
H. Lalande ◽  
F. Courchesne ◽  
S. Savoie
Keyword(s):  
Stream Water ◽  
Base Cations ◽  
Stream Chemistry ◽  
Stream Water Chemistry ◽  
The Matrix ◽  
Adsorption Desorption ◽  
The Relationship ◽  
Best Fit ◽  
Spring Snowmelt ◽  
Over Time

In order to determine how water flowpath controls stream chemistry, we studied both soil and stream water during spring snowmelt, 1985. Soil solution concentrations of base cations were relatively constant over time indicating that cation exchange was controlling cation concentrations. Similarly SO4 adsorption-desorption or precipitation-dissolution reactions with the matrix were controlling its concentrations. On the other hand, NO3 appeared to be controlled by uptake by plants or microorganisms or by denitrification since their concentrations in the soil fell abruptly as snowmelt proceeded. Dissolved Al and pH varied vertically in the soil profile and their pattern in the stream indicated clearly the importance of water flowpath on stream chemistry. Although Al increased as pH decreased, the relationship does not appear to be controlled by gibbsite. The best fit of calculated dissolved inorganic Al was obtained using AlOHSO4 with a solubility less than that of pure crystalline jurbanite.

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