scholarly journals A Review on Natural Fiber-Reinforced Geopolymer and Cement-Based Composites

Materials ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 4603
Author(s):  
Marfa Camargo ◽  
Eyerusalem Adefrs Taye ◽  
Judith Roether ◽  
Daniel Tilahun Redda ◽  
Aldo Boccaccini
Keyword(s):  
New Technologies ◽  
Moisture Absorption ◽  
Natural Fiber ◽  
Natural Fibers ◽  
Industrial Applications ◽  
Synthetic Fiber ◽  
Matrix Interface ◽  
The Matrix ◽  
Fiber Matrix Interface ◽  
Fiber Matrix

The use of ecological materials for building and industrial applications contributes to minimizing the environmental impact of new technologies. In this context, the cement and geopolymer sectors are considering natural fibers as sustainable reinforcement for developing composites. Natural fibers are renewable, biodegradable, and non-toxic, and they exhibit attractive mechanical properties in comparison with their synthetic fiber counterparts. However, their hydrophilic character makes them vulnerable to high volumes of moisture absorption, thus conferring poor wetting with the matrix and weakening the fiber–matrix interface. Therefore, modification and functionalization strategies for natural fibers to tailor interface properties and to improve the durability and mechanical behavior of cement and geopolymer-based composites become highly important. This paper presents a review of the physical, chemical and biological pre-treatments that have been performed on natural fibers, their results and effects on the fiber–matrix interface of cement and geopolymer composites. In addition, the degradation mechanisms of natural fibers used in such composites are discussed. This review finalizes with concluding remarks and recommendations to be addressed through further in-depth studies in the field.

scholarly journals Critical Review of the Parameters Affecting the Effectiveness of Moisture Absorption Treatments Used for Natural Composites

2019 ◽  
Vol 3 (1) ◽  
pp. 27 ◽  
Author(s):  
Ahmad Al-Maharma ◽  
Naser Al-Huniti
Keyword(s):  
Moisture Absorption ◽  
Natural Fiber ◽  
Natural Fibers ◽  
Complete Discussion ◽  
Natural Composites ◽  
Review Study ◽  
Fiber Matrix ◽  
Physical Treatments ◽  
The Cost ◽  
High Degree

Natural composites can be fabricated through reinforcing either synthetic or bio-based polymers with hydrophilic natural fibers. Ultimate moisture absorption resistance at the fiber–matrix interface can be achieved when hydrophilic natural fibers are used to reinforce biopolymers due to the high degree of compatibility between them. However, the cost of biopolymers is several times higher than that of their synthetic counterparts, which hinders their dissemination in various industries. In order to produce economically feasible natural composites, synthetic resins are frequently reinforced with hydrophilic fibers, which increases the incompatibility issues such as the creation of voids and delamination at fiber–matrix interfaces. Therefore, applying chemical and/or physical treatments to eliminate the aforementioned drawbacks is of primary importance. However, it is demonstrated through this review study that these treatments do not guarantee a sufficient improvement of the moisture absorption properties of natural composites, and the moisture treatments should be applied under the consideration of the following parameters: (i) type of hosting matrix; (ii) type of natural fiber; (iii) loading of natural fiber; (iv) the hybridization of natural fibers with mineral/synthetic counterparts; (v) implantation of nanofillers. Complete discussion about each of these parameters is developed through this study.

Prediction of the Fiber-Matrix Interface Failure due to Longitudinal Tensile Loading Using Finite Element Methods

1994 ◽  
Vol 365 ◽  
Author(s):  
Hassan Mahfuz ◽  
A.K.M. Ahsan Mian ◽  
Uday K. Vaidya ◽  
Timothy Brown ◽  
Shaik Jeelani
Keyword(s):  
Local Stress ◽  
Tensile Loading ◽  
Mechanical Tests ◽  
Matrix Interface ◽  
Interface Failure ◽  
Strain Behavior ◽  
The Matrix ◽  
Fiber Matrix Interface ◽  
Fiber Matrix ◽  
Composite Response

ABSTRACTA 3D-unit cell for 0/90 laminated composites has been developed to predict the composite behavior under longitudinal tensile loading condition. 3D contact element has been used to model the fiber matrix interface. Two interface conditions, namely, infinitely strong and weakly bonded, are considered in the analysis. Both large displacement and plastic strain behavior for the matrix are considered to account for the geometric and material non-linearities. Investigations were carried out at three temperatures to compare the composite response obtained from mechanical tests at those temperatures. Stress-strain behavior and the local stress distributions at the fiber as well as at the matrix are presented, and their effects on the failure of the interface are discussed in the paper. The material under investigation was SiCf/Si3N4.

Fabrication and Testing of Abaca Fibre Reinforced Epoxy Composites for Automotive Applications

2013 ◽  
Vol 718-720 ◽  
pp. 63-68 ◽  
Author(s):  
Raja R. Niranjan ◽  
S. Junaid Kokan ◽  
R. Sathya Narayanan ◽  
S. Rajesh ◽  
V.M. Manickavasagam ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Natural Fiber ◽  
Fibre Composite ◽  
Fiber Composite ◽  
Salt Water ◽  
Natural Fibers ◽  
Natural Fibre ◽  
Industrial Applications ◽  
Vertical Orientation ◽  
The Matrix

The natural fibre composite materials are nowadays playing a vital role in replacing the conventional and synthetic materials for industrial applications. This paper proposes a natural fiber composite made of Abaca fibre as reinforcing agent with Epoxy resin as the matrix, manufactured using Hand Lay-up method. Glass Fiber Reinforced Plastics (woven rovings) are used to improve the surface finish and impart more strength and stiffness to natural fibers. In this work, the fibers are arranged in alternative layers of abaca in horizontal and vertical orientation. The mechanical properties of the composite are determined by testing the samples for tensile and flexural strength. It is observed that the tensile strength of the composite material is dependent on the strength of the natural fiber and also on the interfacial adhesion between the reinforcement and the matrix. The composite is developed for automobile dashboard/mudguard application. It may also be extended to biomedical, electronics and sports goods manufacturing. It can also be used in marine products due to excellent resistance of abaca to salt water damage since the tensile strength when it is wet.

scholarly journals Multiscale Characterization of Nanoengineered Fiber-Reinforced Composites: Effect of Carbon Nanotubes on the Out-of-Plane Mechanical Behavior

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Carlos Medina ◽  
Eduardo Fernandez ◽  
Alexis Salas ◽  
Fernando Naya ◽  
Jon Molina-Aldereguía ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Fracture Toughness ◽  
Shear Strength ◽  
Mechanical Behavior ◽  
Matrix Interface ◽  
Short Beam ◽  
The Matrix ◽  
Fiber Matrix Interface ◽  
Fiber Matrix

The mechanical properties of the matrix and the fiber/matrix interface have a relevant influence over the mechanical properties of a composite. In this work, a glass fiber-reinforced composite is manufactured using a carbon nanotubes (CNTs) doped epoxy matrix. The influence of the CNTs on the material mechanical behavior is evaluated on the resin, on the fiber/matrix interface, and on the composite. On resin, the incorporation of CNTs increased the hardness by 6% and decreased the fracture toughness by 17%. On the fiber/matrix interface, the interfacial shear strength (IFSS) increased by 22% for the nanoengineered composite (nFRC). The influence of the CNTs on the composite behavior was evaluated by through-thickness compression, short beam flexural, and intraply fracture tests. The compressive strength increased by 6% for the nFRC, attributed to the rise of the matrix hardness and the fiber/matrix IFSS. In contrast, the interlaminar shear strength (ILSS) obtained from the short beam tests was reduced by 8% for the nFRC; this is attributed to the detriment of the matrix fracture toughness. The intraply fracture test showed no significant influence of the CNTs on the fracture energy; however, the failure mode changed from brittle to ductile in the presence of the CNTs.

Fiber-Matrix Bonding in Boron-Reinforced Aluminum Composites

1969 ◽  
Vol 27 ◽  
pp. 32-33
Author(s):  
I. Corvin ◽  
H. Morrow ◽  
O. Johari ◽  
N. Parikh
Keyword(s):  
Aluminum Matrix ◽  
Surface Characteristics ◽  
Aluminum Matrix Composites ◽  
Matrix Composites ◽  
Matrix Interface ◽  
Boron Fiber ◽  
The Matrix ◽  
Fiber Matrix Interface ◽  
Fiber Matrix

A significant amount of research has been done in the past few years in the development of suitable composite materials in general and on boron fiber-aluminum matrix composites in particular. The mechanical properties of the composite depend on the structures and strengths of the matrix and fibers; on the amount, distribution, and surface characteristics of the fibers; and on the quality of the bond at the fiber-matrix interface. The results presented here illustrate the application of the SEM in studying the structure of the fiber-matrix interface and the fracture features of boron and aluminum.

Measuring Interface Strength in Single Fiber Composites: The Effect of Stress Concentrations

2000 ◽  
Vol 629 ◽  
Author(s):  
G. A. Holmes ◽  
R. C. Peterson
Keyword(s):  
Fragment Length ◽  
Interface Strength ◽  
Matrix Interface ◽  
Stress Concentrations ◽  
New Model ◽  
Testing Rate ◽  
Mechanics Model ◽  
The Matrix ◽  
Fiber Matrix Interface ◽  
Fiber Matrix

ABSTRACTFiber-matrix interface strength is known to be a critical factor in controlling the long-term performance of structural composites. This parameter is often obtained by using the average fragment length data generated from the single-fiber fragmentation test (SFFT). The interfacial shear strength is then determined by using this data in a micro-mechanics model that describes the shear-stress transfer process between the matrix and the fiber. Recently, a non-linear viscoelastic micro-mechanics model was developed to more accurately account for the matrix material properties. This new model indicates that the interface strength is dependent on the testing rate. Experimentally, it has been shown that the final fragment length distribution in some systems is dependent on the testing rate. However, data analysis using the new model indicates that the distribution change with testing rate is promoted by the presence of high stress concentrations at the end of the fiber fragments. From the model, these stress concentrations were found to exist at very low strain values. Experimentally, the fragment distributions obtained from specimens tested by different testing rates were found to be significantly different at strain values well below the strain values required to complete the test. These results are consistent with the research of Jahankhani and Galiotis and finite element calculations performed by Carrara and McGarry. These authors concluded that stress concentrations can promote failure of the fiber-matrix interface on the molecular level. Our results support this conclusion. In addition, our research results suggest that altering the SFFT testing rate can lower the magnitude of these stress concentrations and minimize failure of the fiber-matrix interface.

Review of Natural Fiber Reinforced Elastomer Composites

2018 ◽  
Author(s):  
Pantea Kooshki ◽  
Tsz-Ho Kwok
Keyword(s):  
Mechanical Properties ◽  
Natural Fiber ◽  
Low Cost ◽  
Natural Fibers ◽  
Fiber Surface ◽  
Specific Strength ◽  
Elastomeric Matrix ◽  
The Matrix ◽  
Fiber Matrix ◽  
Physical Treatments

This paper is a review on mechanical characteristics of natural fibers reinforced elastomers (both thermoplastics and thermosets). Increasing environmental concerns and reduction of petroleum resources attracts researchers attention to new green eco-friendly materials. To solve these environmental related issues, cellulosic fibers are used as reinforcement in composite materials. These days natural fibers are at the center of attention as a replacement for synthetic fibers like glass, carbon, and aramid fibers due to their low cost, satisfactory mechanical properties, high specific strength, renewable resources usage and biodegradability. The hydrophilic property of natural fibers decreases their compatibility with the elastomeric matrix during composite fabrication leading to the poor fiber-matrix adhesion. This causes low mechanical properties which is one of the disadvantages of green composites. Many researches have been done modifying fiber surface to enhance interfacial adhesion between filler particles and elastomeric matrix, as well as their dispersion in the matrix, which can significantly affect mechanical properties of the composites. Different chemical and physical treatments are applied to improve fiber/matrix interlocking.

Applications of Bio-Composites in Industrial Products

2001 ◽  
Vol 702 ◽  
Author(s):  
Prabhu Kandachar ◽  
Rik Brouwer
Keyword(s):  
Biodegradable Polymers ◽  
Moisture Absorption ◽  
Natural Fiber ◽  
Natural Fibers ◽  
Fiber Composites ◽  
Point Of View ◽  
Synthetic Fiber ◽  
Attractive Alternative ◽  
Natural Fiber Composites ◽  
Synthetic Fibers

ABSTRACTAvailable as agricultural resources in many countries, natural fibers, such as flax, hemp, kenaf, exhibit mechanical properties comparable to those of synthetic fibers like glass. But they are lighter, biodegradable, and are often claimed to be less expensive. Composites with these natural fibers have the potential to be attractive alternative to synthetic fiber composites. The natural fibers, however, exhibit more scatter in their properties, are thermally less stable and are sensitive to moisture absorption. The choice of matrix to reinforce with these fibers therefore becomes critical.Currently, synthetic non-biodegradable polymers, such as polypropylene, polyester, etc., are being explored as matrix materials, for applications in sectors like automobiles and buildings. Biodegradable polymers, if made available in sufficient quantities at affordable prices, pave way for bio-composites in future. With both matrix and fibers being biodegradable, bio-composites become attractive candidates from the environment point of view.Extensive and reliable property data on natural fiber composites and/or on bio-composites, are still lacking, making product design with these materials rather tedious. Once the database is available, design & manufacture of products with natural fiber composites and biocomposites offer several opportunities and challenges.

Effect of Microvoids on Anomalous Moisture Absorption of Quartz/BMI Composite Laminates

2014 ◽  
Author(s):  
Keith R. Hurdelbrink ◽  
Gorkem E. Guloglu ◽  
Jacob P. Anderson ◽  
Landon R. Grace ◽  
Zahed Siddique ◽  
...  
Keyword(s):  
Fiber Volume Fraction ◽  
Moisture Absorption ◽  
Volume Fraction ◽  
Model Parameters ◽  
Absorption Model ◽  
Matrix Interface ◽  
Fiber Volume ◽  
One Dimensional ◽  
Fiber Matrix Interface ◽  
Fiber Matrix

The focus of this paper was to investigate the effects of microvoid content in quartz/BMI laminates on both short and long-term moisture absorption dynamics. The moisture absorption characteristics for the laminates were experimentally obtained by water immersion tests at 25°C of three-ply quartz/BMI samples that contain voids, ranging from 8.6% to 13.7% by volume. The void levels were obtained by conditioning the prepreg at different moisture levels for 48 hours in an environmental chamber before curing in a hot press. The curing process was carried out at 69 kPa, which leads to a more uniform fiber volume fraction for the laminates. Having a constant fiber volume fraction ensures the same amount of fiber-matrix interface present in all the test samples, therefore eliminating the effect of fiber-matrix interface as an experimental variable. It is shown that the presence of microvoids leads to an increased non-Fickian absorption behavior. Hence, the anomalous, non-Fickian absorption parameters are obtained by using a one-dimensional absorption model that accounts for both bound and unbound free water within the laminate. It is shown that the microvoids act as storage sites for moisture which can be described by the one-dimensional, non-Fickian absorption model. Finally, possible relationships between the four absorption model parameters and the process-induced microvoid content are discussed.

Sign in / Sign up

Export Citation Format

Share Document