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 Preparation of Long Sisal Fiber-Reinforced Polylactic Acid Biocomposites with Highly Improved Mechanical Performance

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1124
Author(s):  
Zhifang Liang ◽  
Hongwu Wu ◽  
Ruipu Liu ◽  
Caiquan Wu
Keyword(s):  
Mechanical Properties ◽  
Polylactic Acid ◽  
Mechanical Performance ◽  
Tensile Elongation ◽  
Sisal Fiber ◽  
Fiber Reinforced ◽  
Impact Performance ◽  
The Matrix ◽  
Blending Process ◽  
Extension Direction

Green biodegradable plastics have come into focus as an alternative to restricted plastic products. In this paper, continuous long sisal fiber (SF)/polylactic acid (PLA) premixes were prepared by an extrusion-rolling blending process, and then unidirectional continuous long sisal fiber-reinforced PLA composites (LSFCs) were prepared by compression molding to explore the effect of long fiber on the mechanical properties of sisal fiber-reinforced composites. As a comparison, random short sisal fiber-reinforced PLA composites (SSFCs) were prepared by open milling and molding. The experimental results show that continuous long sisal fiber/PLA premixes could be successfully obtained from this pre-blending process. It was found that the presence of long sisal fibers could greatly improve the tensile strength of LSFC material along the fiber extension direction and slightly increase its tensile elongation. Continuous long fibers in LSFCs could greatly participate in supporting the load applied to the composite material. However, when comparing the mechanical properties of the two composite materials, the poor compatibility between the fiber and the matrix made fiber’s reinforcement effect not well reflected in SSFCs. Similarly, the flexural performance and impact performance of LSFCs had been improved considerably versus SSFCs.

Microstructure and Mechanical Performance of AZ31-1.7 Wt.% Si Alloy Processed by Cyclic Channel Die Compression

2010 ◽  
Vol 667-669 ◽  
pp. 457-461
Author(s):  
Wei Guo ◽  
Qu Dong Wang ◽  
Man Ping Liu ◽  
Tao Peng ◽  
Xin Tao Liu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Tensile Strength ◽  
Mechanical Performance ◽  
Chinese Script ◽  
Cast State ◽  
Microstructure And Mechanical Properties ◽  
Mean Grain Size ◽  
The Matrix ◽  
The Mean

Cyclic channel die compression (CCDC) of AZ31-1.7 wt.% Si alloy was performed up to 5 passes at 623 K in order to investigate the microstructure and mechanical properties of compressed alloys. The results show that multi-pass CCDC is very effective to refine the matrix grain and Mg2Si phases. After the alloy is processed for 5 passes, the mean grain size decreases from 300 μm of as-cast to 8 μm. Both dendritic and Chinese script type Mg2Si phases break into small polygonal pieces and distribute uniformly in the matrix. The tensile strength increases prominently from 118 MPa to 216 MPa, whereas the hardness of alloy deformed 5 passes only increase by 8.4% compared with as-cast state.

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.

Manufacturing Techniques and Mechanical Properties of Recycle High-Strength PET Compound Nonwoven

2012 ◽  
Vol 627 ◽  
pp. 321-324 ◽  
Author(s):  
Ching Wen Lou ◽  
An Pang Chen ◽  
Jan Yi Lin ◽  
Mei Chen Lin ◽  
Jin Mao Chen ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
High Strength ◽  
Polyester Fiber ◽  
Chemical Fiber ◽  
Machine Direction ◽  
Cross Direction ◽  
Nonwoven Fabrics ◽  
The Matrix ◽  
Manufacturing Techniques

The high-strength polyester fiber is a kind of chemical fiber that is rapidly developed and widely applied. With development of technology, the demands for polyester fiber are becoming more and more. Furthermore, the high-strength polyester fiber, used to reinforce the matrix, has higher modulus and strength than commercial polyester fiber. In this research, the 15D polyester fiber, the low melting polyester and the high-strength polyester fiber were used to manufacture the high-strength PET compound nonwoven fabrics by nonwoven processing. Afterwards, the mechanical properties of the PET compound nonwoven was measured both at cross direction and machine direction.

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.

Mechanical Properties of Densified Untwisted Carbon Nanotube Yarn / Epoxy Composites

2015 ◽  
Author(s):  
Risa Yoshizaki ◽  
Kim Tae Sung ◽  
Atsushi Hosoi ◽  
Hiroyuki Kawada
Keyword(s):  
Mechanical Properties ◽  
Volume Fraction ◽  
Polymer Matrix Composites ◽  
High Strength ◽  
Matrix Composites ◽  
Specific Strength ◽  
The Matrix ◽  
Cnt Arrays ◽  
Strength And Stiffness ◽  
Long Fibers

Carbon nanotubes (CNTs) have very high specific strength and stiffness. The excellent properties make it possible to enhance the mechanical properties of polymer matrix composites. However, it is difficult to use CNTs as the reinforcement of long fibers because of the limitation of CNT growth. In recent years, a method to spin yarns from CNT forests has developed. We have succeeded in manufacturing the unidirectional composites reinforced with the densified untwisted CNT yarns. The untwisted CNT yarns have been manufactured by drawing CNTs through a die from vertically aligned CNT arrays. In this study, the densified untwisted CNT yarns with a polymer treatment were fabricated. The tensile strength and the elastic modulus of the yarns were improved significantly by the treatment, and they were 1.9 GPa and 140 GPa, respectively. Moreover, the polymer treatment prevented the CNT yarns from swelling due to impregnation of the matrix resin. Finally, the high strength CNT yarn composites which have higher volume fraction than a conventional method were successfully fabricated.

scholarly journals Mechanical properties of concrete for radioactive waste repositories

2019 ◽  
Vol 282 ◽  
pp. 02104
Author(s):  
Dana Koňáková ◽  
Eva Vejmelková ◽  
Vojtěch Pommer ◽  
Lenka Scheinherrová ◽  
Petr Konvalinka ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Radioactive Waste ◽  
Lower Percentage ◽  
Mechanical Parameters ◽  
Suitable Material ◽  
Concrete Mixtures ◽  
The Matrix ◽  
Negative Effect ◽  
Radioactive Waste Repositories ◽  
Waste Repositories

Concrete casing for radioactive repositories have to meet many strict requirements. One of the most important is a radiation protection and a radionuclide inhabitation. Bentonite, with a great sorption capacity, seems to be a suitable material for this purpose. Therefore, the main aim of this study was to assess an impact of the bentonite utilization as a component in concrete mixtures. For this reason, basic physical properties and mechanical parameters of concretes containing different amount of bentonite were determined. Bentonite applications led to the open porosity growth, while the matrix densities were not influenced. Regarding the mechanical parameters, the compressive strengths as well as the flexural strengths were significantly deteriorated by the bentonite application. Despite the presented negative effect, the obtained results seems to prove a possible applicability of a lower percentage of bentonite in concrete structures not as a cement replacement, but just as a component.

A study on some properties of thin biocomposites made from unbeaten wood and non-wood pulps

2012 ◽  
Vol 19 (3) ◽  
pp. 287-293
Author(s):  
Arif Karademir ◽  
Hulya Varlibas ◽  
Selim Karahan
Keyword(s):  
Short Fibers ◽  
Chemical Additives ◽  
Fine Content ◽  
Plant Fibers ◽  
Tensile Index ◽  
Density Values ◽  
Formation Method ◽  
Wood Pulps ◽  
Long Fibers ◽  
Sheet Sample

AbstractA number of thin biomaterials were prepared via a wet formation method from seven different unbeaten plant fibers without using any chemical additives. It is noted that sheets made with short fibers (Flax-B: 0.32 mm and Straw-UB: 0.36 mm) and high fine content (Flax-B: 9.77% and Straw-UB: 10.64%) showed higher tensile index values (Flax-B: 27 Nm/g and Straw-UB: 25 Nm/g) than those made from long fibers. Despite having the longest fibers (1.11 mm) in studied samples, the tensile index values of sheet sample made from Pine-S-UB was just 12 Nm/g, which is just half of short-fibered (0.36 mm) straw sheets. Air permeability of sheets made from Pine-S-UB and Straw-UB were 5322 and 917 ml/min, respectively. Densities of the same sheets in the same order were 493 and 539 kg/m3. It is concluded that long cellulose fibers actually produce bulky materials with limited interfiber contacting areas, while short ones give biocomposites with higher density values indicating a firmly compacted internal structure in the case of utilizing plant fibers without beating and refining. Results would be usable when producing biocomposites from plant fibers via wet formation followed by various resins and polymer moldings.

scholarly journals Investigation of Weight Fraction and Alkaline Treatment on Catechu Linnaeus/Hibiscus cannabinus/Sansevieria Ehrenbergii Plant Fibers-Reinforced Epoxy Hybrid Composites

2022 ◽  
Vol 2022 ◽  
pp. 1-9
Author(s):  
R. Rangaraj ◽  
S. Sathish ◽  
T. L. D. Mansadevi ◽  
R. Supriya ◽  
Raviteja Surakasi ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Impact Strength ◽  
Hybrid Composites ◽  
Weight Fraction ◽  
Alkaline Treatment ◽  
Fiber Composites ◽  
Hibiscus Cannabinus ◽  
Plant Fibers ◽  
The Matrix ◽  
Treated Fiber

The aim of the present work is to develop novel hybrid composites using areca, kenaf, and snake grass fibers as reinforcement and epoxy as the matrix. The areca, kenaf, and snake grass fibers were extracted from Catechu Linnaeus, Hibiscus cannabinus, and Sansevieria Ehrenbergii plants, respectively, and treated with 5% NaOH to improve the interfacial adhesion between the hydrophilic fiber and the hydrophobic matrix. Hybrid composites were developed by the compression molding technique and formulated based on the weight fraction of fibers. Tensile, flexural, and impact strength and hardness samples were prepared as per ASTM D 3039, ASTM D 790, ASTM D 256, and ASTM D 2240, respectively. The effects of alkaline treatment on developed hybrid composites were investigated. The developed hybrid composites with 20% wt. snake grass and 10% wt. areca fiber present interesting mechanical properties with a tensile strength of 58 MPa, flexural strength of 124 MPa, impact strength of 5.24 kJ/m2, and hardness of 88. The results indicate that maximum mechanical properties were obtained for alkaline-treated fiber composites with 20% wt. snake grass fiber compared to untreated fiber composites owing to better adhesion between the treated fiber and the matrix. The effect of alkaline treatment was analyzed by Fourier transform infrared. The fractured surfaces of tested samples were analyzed by scanning electron microscopy.

Static and Dynamic Mechanical Performance of Carbon Fiber Reinforced Polyethersulfone Composites

2019 ◽  
Vol 895 ◽  
pp. 265-271 ◽  
Author(s):  
B. Harshavardhan ◽  
R. Ravishankar ◽  
Bheemappa Suresha ◽  
S. Srinivas
Keyword(s):  
Mechanical Properties ◽  
Carbon Fiber ◽  
Mechanical Performance ◽  
Mechanical Test ◽  
Dynamic Environment ◽  
Flexural Properties ◽  
Static Properties ◽  
Dynamic Mechanical ◽  
The Matrix ◽  
Static Mechanical

This study has been carried out to demonstrate the effect of short carbon fiber (SCF) loading on static and dynamic mechanical performance of polyethersulfone (PES) composites. Different combinations of SCF/PES composites were prepared by extrusion followed by injection molding. The static mechanical properties such as hardness, tensile and flexural properties of PES based composites were analyzed following ISO standards. As engineering materials, the polymer composites with high modulus as well as excellent damping properties are of great interest in aerospace and automotive industries for severe dynamic environment. Furthermore, in addition to static properties of composites, dynamic mechanical behaviour of PES based composites was evaluated. Mechanical test results showed that increasing the SCF wt. % in the composites increases the hardness, tensile and flexural properties. Furthermore, the optimal SCF loading was found to be 30 wt. % for significantly improving the overall composite mechanical performance. Upon the reinforcing of SCFs, an improvement in the storage modulus was found. Based on the fractographic analysis, orientation and aligned structure of carbon fibers, good bonding of fibers within the matrix and better fiber-matrix interaction were the primary reasons leading to the improvement of mechanical properties. The optimized composite (PES with 30 wt. % of SCF) could be used in automotive components like frames, flap covers and gears of printing machinery.

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