Добірка наукової літератури з теми "Plant fibers Mechanical properties"
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся зі списками актуальних статей, книг, дисертацій, тез та інших наукових джерел на тему "Plant fibers Mechanical properties".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Статті в журналах з теми "Plant fibers Mechanical properties"
1
Guo, Xing Mei, and Yi Ping Qiu. "Hemp Fiber Reinforced Composites: Morphological and Mechanical Properties." Advanced Materials Research 332-334 (September 2011): 121–25. http://dx.doi.org/10.4028/www.scientific.net/amr.332-334.121.
Повний текст джерелаАнотація:
The use of natural plant fibers as reinforcing fillers in fiber-polymer composites has drawn much interest in recent years. Natural plant fibers as reinforcing fillers have several advantages over inorganic fillers such as glass fibers; they are abundant, readily available, renewable, inexpensive, biodegradable, of low density, and of high specific strength. Hemp fibers are one of the most attractive natural plant fibers for fiber-reinforced composites because of their exceptional specific stiffness. In this review, we summarize recent progress in developments of the hemp fiber reinforced composites such as hemp fiber reinforced unsaturated polyester (UPE), hemp fiber reinforced polypropylene (PP), hemp fiber reinforced epoxy composites, and so on, illustrate with examples how they work, and discuss their intrinsic fundamentals and optimization designs. We are expecting the review to pave the way for developing fiber-polymer composites with higher strength.
2
Ndoumou, Rémy Legrand, Damien Soulat, Ahmad Rashed Labanieh, Manuela Ferreira, Lucien Meva’a, and Jean Atangana Ateba. "Characterization of Tensile Properties of Cola lepidota Fibers." Fibers 10, no. 1 (January 12, 2022): 6. http://dx.doi.org/10.3390/fib10010006.
Повний текст джерелаАнотація:
Plant fibers are being increasingly explored for their use in engineering polymers and composites, and many works have described their properties, especially for flax and hemp fibers. Nevertheless, the availability of plant fibers varies according to the geographical location on the planet. This study presents the first work on the mechanical properties of a tropical fiber extracted from the bast of Cola lepidota (CL) plant. After a debarking step, CL fibers were extracted manually by wet-retting. The tensile properties are first identified experimentally at the fibers scale, and the analysis of the results shows the great influence of the cross-section parameters (diameter, intrinsic porosities) on these properties. Tensile properties of CL fibers are also predicted by the impregnated fiber bundle test (IFBT). At this scale of bundles, a hackling step, which reduces shives and contributes to the parallelization of the fibers within bundles, improves tensile properties predicted by IFBT. The comparison with the properties of plant fibers given in the literature shows that CL fibers have tensile properties in the same range as kenaf, flax or hemp fibers.
3
Zhong, Yucheng, Umeyr Kureemun, Le Quan Ngoc Tran, and Heow Pueh Lee. "Natural Plant Fiber Composites-Constituent Properties and Challenges in Numerical Modeling and Simulations." International Journal of Applied Mechanics 09, no. 04 (May 7, 2017): 1750045. http://dx.doi.org/10.1142/s1758825117500454.
Повний текст джерелаАнотація:
Natural fibers are extracted from natural resources such as stems of plants. In contrast to synthetic fibers (e.g., carbon fibers), natural fibers are from renewable resources and are eco-friendlier. Plant fibers are important members of natural fibers. Review papers discussing the microstructures, performances and applications of natural plant fiber composites are available in the literature. However, there are relatively fewer review reports focusing on the modeling of the mechanical properties of plant fiber composites. The microstructures and mechanical behavior of plant fiber composites are briefly introduced by highlighting their characteristics that need to be considered prior to modeling. Numerical works that have already been carried out are discussed and summarized. Unlike synthetic fibers, natural plant fiber composites have not received sufficient attention in terms of numerical simulations. Existing technical challenges in this subject are summarized to provide potential opportunities for future research.
4
Lv, Chun, Jie Liu, Guoliang Guo, and Yanming Zhang. "The Mechanical Properties of Plant Fiber-Reinforced Geopolymers: A Review." Polymers 14, no. 19 (October 2, 2022): 4134. http://dx.doi.org/10.3390/polym14194134.
Повний текст джерелаАнотація:
Both geopolymer and plant fiber (PF) meet the requirements of sustainable development. Geopolymers have the advantages of simple preparation process, conservation and environmental protection, high early strength, wide source of raw materials, and low cost. They have broad application prospects and are considered as the most potential cementitious materials to replace cement. However, due to the ceramic-like shape and brittleness of geopolymers, their flexural strength and tensile strength are poor, and they are sensitive to microcracks. In order to solve the brittleness problem of geopolymers, the toughness of composites can be improved by adding fibers. Adding fibers to geopolymers can limit the growth of cracks and enhance the ductility, toughness and tensile strength of geopolymers. PF is a good natural polymer material, with the advantages of low density, high aspect ratio. It is not only cheap, easy to obtain, abundant sources, but also can be repeatedly processed and biodegradable. PF has high strength and low hardness, which can improve the toughness of composites. Nowadays, the research and engineering application of plant fiber-reinforced geopolymers (PFRGs) are more and more extensive. In this paper, the recent studies on mechanical properties of PFRGs were reviewed. The characteristics of plant fibers and the composition, structure and properties of geopolymers were reviewed. The compatibility of geopolymer material and plant fiber and the degradation of fiber in the substrate were analyzed. From the perspective of the effect of plant fibers on the compression, tensile and bending properties of geopolymer, the reinforcing mechanism of plant fibers on geopolymer was analyzed. Meanwhile, the effect of PF pretreatment on the mechanical properties of the PFRGs was analyzed. Through the comprehensive analysis of PFFRGs, the limitations and recommendations of PFFRG are put forward.
5
Madsen, Bo, and E. Kristofer Gamstedt. "Wood versus Plant Fibers: Similarities and Differences in Composite Applications." Advances in Materials Science and Engineering 2013 (2013): 1–14. http://dx.doi.org/10.1155/2013/564346.
Повний текст джерелаАнотація:
The work on cellulose fiber composites is typically strictly divided into two separated research fields depending on the fiber origin, that is, from wood and from annual plants, representing the two different industries of forest and agriculture, respectively. The present paper evaluates in parallel wood fibers and plant fibers to highlight their similarities and differences regarding their use as reinforcement in composites and to enable mutual transfer of knowledge and technology between the two research fields. The paper gives an introduction to the morphology, chemistry, and ultrastructure of the fibers, the modeling of the mechanical properties of the fibers, the fiber preforms available for manufacturing of composites, the typical mechanical properties of the composites, the modeling of the mechanical properties with focus on composites having a random fiber orientation and a non-negligible porosity content, and finally, the moisture sensitivity of the composites. The performance of wood and plant fiber composites is compared to the synthetic glass and carbon fibers conventionally used for composites, and advantages and disadvantages of the different fibers are discussed.
6
Li, Yan, Yan Ping Hu, Chun Jing Hu, and Ye Hong Yu. "Microstructures and Mechanical Properties of Natural Fibers." Advanced Materials Research 33-37 (March 2008): 553–58. http://dx.doi.org/10.4028/www.scientific.net/amr.33-37.553.
Повний текст джерелаАнотація:
Natural fibers are excellent substitute materials for man made fibers in making fiber reinforced composites due to their high specific strength and modulus, low density, low price, easy availability in some countries, recyclable and degradable properties. They have raised great attentions among material scientists and engineers in the past decade. Many researches have been conducted to study the mechanical properties, especially interfacial properties of natural fiber reinforced composites. However, the properties, such as mechanical performances, moisture absorption behaviors, et. al of natural fibers themselves have been seldom investigated. Knowing the relationship between microstructures and properties of natural fibers are important for understanding the bulk properties of natural fiber composites and also good instructions for designing bio-mimic materials. In this study, four kinds of natural fibers which were extracted from different plant sources were investigated. The microstructures of these natural fibers were revealed with the aid of optical microscopy. Microstructure models were thereof set up and mechanical properties for the representative volume element were assumed. Fiber bundle fracture models together with probability statistics analysis were employed to calculate the mechanical properties of natural fibers. The results were compared with the experimental measurements. Different mechanical behaviors of natural fibers which were functioned differently in the nature were clearly explained by the above studies
7
SAOUSSEN, ZANNEN, ZOUARI RIADH, HASSEN MOHAMED BEN, JEANMICHEL LAURENCE, and MOLINA STEPHANE. "Design of high mechanical and thermal resistant composites using marine plant waste." Industria Textila 69, no. 06 (January 1, 2019): 446–50. http://dx.doi.org/10.35530/it.069.06.1515.
Повний текст джерелаАнотація:
We investigate the mechanical and thermal properties of a composite structure manufactured from polypropylene matrix reinforced with marine waste fibers, Posidonia oceanica. We show that this fiber largely available on Mediterranean coasts presents many advantages compared to other natural fibers conventionally used as reinforcement. In fact, Posidonia fiber is extracted easily with only mechanical action. Moreover, it enhances the mechanical properties of the whole composite without any need of compatibilizers due to its hydrophobicity. Finally, apart from the mechanical performances, we demonstrate that the incorporation of the fiber with high ratio does not degrade its thermal properties which are a specificity of thermally resistant fibers that could open a wide range of applications.
8
Patel, Mr Ashish Kumar. "Mechanical Properties of Luffa Cylindrica and Coconut Coir Reinforced Epoxy Hybrid Composite." International Journal for Research in Applied Science and Engineering Technology 9, no. 11 (November 30, 2021): 54–65. http://dx.doi.org/10.22214/ijraset.2021.38759.
Повний текст джерелаАнотація:
Abstract: In the current day scenario all the researchers and engineers are searching for a better and cheaper alternative for the current engineering materials. The project deals with the low cost, light weight and biodegradable composites and their use in the current industries. Substituting the legacy fiber reinforced composites with the low-cost natural plant- based fibers reinforced composites help us achieve comparative mechanical properties. India has a quite rich source of natural plant-based fibers which can be used for the production of natural fiber reinforced composites. In this project we used a combination of luffa fibers and coir fibers to produce an epoxy hybrid composite. The current project explores two different problems related to the natural fiber reinforced hybrid composite: 1) Study of mechanical properties of the hybrid thermosetting composite. 2) Study of possibilities of use of natural fiber reinforced epoxy hybrid composites in the different industries
9
Subramaniam, Balasubramani, Manickavasagam V. M, Paul Theophilus Rajakumar I, P. Anantha Christu Raj, Bharath V. G, J. Madhusudhanan, Amit Kumar Sharma, Pravin Patil, and Gizachew Balcha Assefa. "Investigation of Mechanical Properties of Sansevieria cylindrica Fiber/Polyester Composites." Advances in Materials Science and Engineering 2022 (February 28, 2022): 1–6. http://dx.doi.org/10.1155/2022/2180614.
Повний текст джерелаАнотація:
Natural fiber-reinforced composites are the most cost-effective and environmentally friendly alternative to industrial applications. Composite materials reinforced with Sansevieria cylindrica (SC) fibers were developed in this research work. These fibers were chosen for their outstanding mechanical qualities. Compression moulding was used to create composite materials. Each leaf on a Sansevieria cylindrica plant is 20 to 30 mm thick, with a height of 1000 to 2000 mm. The Sansevieria cylindrica (SC) fibers were used as chemically treated fibers and untreated fibers to produce the composites. The tensile strength, hardness, and impact strength of various fiber weight% of composites (20%, 30%, 40%, and 50%) were calculated. From the tested results, the maximum tensile strength achieved in 40 wt% of treated SC fiber composites is 85.7 MPa. The maximum hardness is found in 40 wt% of composites in both treated and untreated fiber composites. The 40 wt% of composites gives a better impact energy of 9.4 J/cm2.The SC fiber polyester composites have superior interfacial bonding and give maximal strength in treated SC fiber composites. The fiber treatment delivers greater strength than the untreated fiber, according to this study. The treated SC fibers have better strength and good bonding between the fiber and matrix to produce the composite materials.
10
Jariwala, Hitesh, and Piyush Jain. "A review on mechanical behavior of natural fiber reinforced polymer composites and its applications." Journal of Reinforced Plastics and Composites 38, no. 10 (February 7, 2019): 441–53. http://dx.doi.org/10.1177/0731684419828524.
Повний текст джерелаАнотація:
In the last decade, natural plant fibers (jute, sisal, coir, banana, hemp, kenaf, flax, etc.) are getting attention from many researchers and academicians to utilize it as an alternate reinforcement of synthetic fiber reinforced polymer composites. These fibers are becoming a great replacement of conventional fibers (such as glass, carbon, and aramid) due to their light weight, low cost, carbon neutrality, fairly good mechanical properties, high specific strength, and biodegradability characteristics. Some chemical treatments are required to enhance the fiber matrix interfacial strength and to minimize the moisture absorption by these fibers which would ultimately improve physico-mechanical properties of these fiber reinforced composites. This paper is a review on mechanical properties of the natural plant fiber reinforced polymer composites and various factors affecting the mechanical performance of it. The tribological behavior of natural fiber reinforced polymer composites and scanning electron microscope analysis are also discussed. Some mathematical models are mentioned which are useful to predict mechanical behavior of the composites. It is found that Halpin–Tsai equation is the most effective equation amongst others in predicting Young’s modulus for short-fiber reinforced composites with minimum error. The applications of natural plant fiber reinforced polymer composites in various engineering fields are discussed.
Дисертації з теми "Plant fibers Mechanical properties"
1
Han, Hongchang. "Study of agro-composite hemp/polypropylene : treatment of fibers, morphological and mechanical characterization." Thesis, Troyes, 2015. http://www.theses.fr/2015TROY0002/document.
Повний текст джерелаАнотація:
L’utilisation des fibres végétales dans les polymères composites suscite de nombreuses investigations. Avant de mélanger les fibres végétales dans le polymère, un traitement chimique peut être effectué permettant de réduire l’hydrophilicité des fibres et d’améliorer l'adhérence à l’interface fibre/matrice. Dans cette thèse, l'eau et l'alcali sont utilisés d'abord pour traiter les fibres de chanvre, puis trois agents silane : 3-(triméthoxysilyl)propyl méthacrylate (MPS), N-[3- (triméthoxysilyl)propyl] aniline (PAPS) et (3-Aminopropyl)-triéthoxysilane (APS), sont utilisés pour modifier plus ou moins la surface des fibres de chanvre. Ces fibres traitées ou modifiées sont ensuite mélangées avec le polypropylène (PP) pour la fabrication des composites. Les effets de ces différents traitements sur la structure, les composants et l’hydrophilicité des fibres, et les propriétés mécaniques de ces composites sont mis en évidence. Nous avons étudié ensuite l’effet de vieillissement sur leurs comportements mécaniques, notamment l'humidité, la température et le rayonnement ultraviolet. Les résultats ont montré que le traitement de fibres par l'eau et l’alcali a des effets considérables sur la structure de fibres, les propriétés mécaniques et la durabilité des composites renforcés. La modification par l'agent de silane a une influence moins importante sur la structure des fibres, pourtant son groupe fonctionnel a une influence significative sur les propriétés mécaniques et la résistance au vieillissement des composites renforcésUsing agro fiber as reinforcement of polymer com-posites attracts numerous investigations due to the good mechanical properties and environmental benefits. Prior to blend agro fiber with polymer, chemical treatment can be employed to treat agro fiber for the purpose of reducing the hydrophilicity of fiber and improving the interfacial adhesion fi-ber/polymer matrix. In this thesis, water and alkali are utilized to treat hemp fiber firstly and then three silane agent as 3-(Trimethoxysilyl)propyl methacry-late (MPS), N-[3-(Trimethoxysilyl)propyl]aniline (PAPS) and (3-Aminopropyl)-triethoxysilane (APS) are employed to modify the hemp fiber surface. These treated or modified fibers are blended respectively with polypropylene (PP) to fabricate the hemp fiber/PP composites. The effects of these different treatments on the structure, components and hydro-philicity of fiber, and the mechanical properties of the reinforced PP composites are studied. Moreover, the accelerated ageing experiments including humidity, temperature and ultraviolet of the reinforced PP composites are conducted. The results showed that the fiber treatment of water and alkali has a considerable effect on fiber structure, mechanical properties and durability of the reinforced compo-sites. The silane agent modification of fiber has less influence on the fiber structure but its functional group has great influence on the mechanical proper-ties and ageing resistance of the reinforced compo-sites
2
Yang, Haomiao. "Study of a unidirectional flax reinforcement for biobased composite." Thesis, Normandie, 2017. http://www.theses.fr/2017NORMC226/document.
Повний текст джерелаАнотація:
Dans cette thèse, un composite unidirectionnel à renfort lin (composite UD biosourcé) a été développé et élaboré par la technique de presse à chaud. Le comportement en traction des composites à renfort végétal montre en général deux domaines, mais un troisième domaine est identifié dans ce travail. Un modèle phénoménologique développé précédemment pour décrire le comportement en traction d'un composite à renfort en fils torsadés a été testé avec le composite UD biosourcé. Nous montrons que l'ajout d'un phénomène de consolidation au modèle précédent est nécessaire pour simuler correctement le troisième domaine. Un second modèle mécanique a été par ailleurs développé pour identifier expérimentalement les propriétés mécaniques effectives du renfort en lin lorsqu'il est piégé dans la matrice. La distribution statistique de l'orientation locale du renfort a été mesurée pour pouvoir prendre en compte l'orientation des fibres. Pour cela, la technique du tenseur de structure a été appliquée sur des images optiques du pli de lin. Par ailleurs, ce modèle permet d'étudier l'influence des porosités sur les propriétés mécaniques. Les deux modèles permettent d'effectuer des prévisions efficaces du comportement mécanique du composite de fibre de lin unidirectionnel. En complément des modèles de mécanique, le comportement en sorption du composite de lin UD a également été analysé. Le modèle de Langmuir et le modèle de Fick ont été appliqués sur nos composites UD. Les résultats montrent que la configuration unidirectionnelle du renfort de lin favorise la sorption d'eau des composites associés.Résumé en anglaisIn this Ph.D work, unidirectional flax fiber composite (UD biobased composite) has been designed and manufactured based on the hot platen press process. Plant fiber composites usually exhibit two regions under tensile load, but three regions have been identified in this work. A phenomenological model, previously developed to describe the tensile mechanical behavior of twisted plant yarn composites, has been tested with the UD biobased composite. We show that the addition of a strengthening phenomenon to the previous model is necessary to simulate correctly the third region. A second mechanical model has also been developed for experimental identification of the effective mechanical properties of flax reinforcement when embeded in matrix. A statistical distribution of local orientation of UD reinforcement was obtained allowing taking the fiber orientation into account. To that end, structure tensor method was applied to optical images of flax ply. Furthermore, this model allows the effect of porosity on mechanical properties to be studied. Both models provide effective forecast of the mechanical behavior of unidirectional flax fiber composite. Besides the mechanic models, sorption behavior of UD flax composite also has been analyzed. Langmuir's model and Fick's model were applied on our UD composite. The results show that the unidirectional configuration of the flax reinforcement promotes the water sorption from the associated composites
3
Wretfors, Christer. "Hemp fibre and reinforcements of wheat gluten plastics /." Alnarp : Dept. of Agriculture - Farming Systems, Technology and Product Quality, Swedish University of Agricultural Sciences, 2008. http://epsilon.slu.se/11236319.pdf.
Повний текст джерела
4
Borchani, Karama. "Développement d'un composite à base d'un polymère biodégradable et de fibres extraites de la plante d'Alfa." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSES010/document.
Повний текст джерелаАнотація:
Cette étude constitue une contribution à la recherche de nouveau matériau composite originaire des ressources naturelles végétales. Elle vise alors à l’exploitation des fibres naturelles extraites de la plante d’Alfa avec une matrice biopolymère thermoplastique de type Mater-Bi® afin d’élaborer des biocomposites. Trois types de fibres courtes extraites de la plante d’Alfa sont préparés ; non traitées et traitées par un traitement alcalin à 1 et 5%. Les diverses techniques utilisées pour la caractérisation des fibres ont révélé une augmentation de la rugosité, du taux de cellulose, de l’indice de cristallinité ainsi de la stabilité thermique après le traitement alcalin. Les matériaux composites sont préparés par extrusion bivis suivi d’une opération d’injection en faisant varier le pourcentage des fibres de 0 à 25%. Les analyses thermiques des biocomposites ont montré un accroissement significatif de la vitesse de cristallisation suite à l'incorporation des fibres d’Alfa ainsi une amélioration de la stabilité thermique pour les matériaux à base de fibres traitées. La résistance à la traction et le module de Young des biocomposites ont augmenté alors que la ténacité et l’allongement à la rupture ont diminué avec l'augmentation du taux de fibres. Les micrographies MEB des surfaces fracturées indiquent une bonne adhésion entre la matrice et les fibres d’Alfa traitées ou non. L’étude de la cinétique de cristallisation des différents biocomposites a prouvé le fort effet nucléant des fibres d’Alfa traitées ou nonThis study is a contribution to the search for new composite material from vegetable natural resources. It aims at the exploitation of natural fibers extracted from the Alfa plant with a bioplastic of the Mater-Bi® type in order to develop biocomposites. Three kinds of short fibers extracted from Alfa plant were prepared; untreated, 1% and 5% alkali treated. The various techniques used for fibers characterization showed an increase in the roughness, cellulose level, crystallinity index and thermal stability after the alkali treatment. The composite materials were prepared by twin screw extrusion flowed by an injection operation by varying the fiber contents of 0 to 25%. Thermal analysis showed significant increase of the crystallization rate with the incorporation of Alfa fibers and enhancement of thermal stability by alkali treatment. Modulus and tensile strength of biocomposites also improved whereas toughness and elongation at break decreased upon increasing the fibers fraction. Scanning electron microscopy (SEM) on fractured surfaces indicated good adhesion between the matrix and the treated or untreated Alfa fibers. The study of crystallization kinetics of biocomposites showed strong nucleating effect of treated or untreated Alfa fibers
5
Zhang, Xiaohui. "Manufacturing of hemp/PP composites and study of its residual stress and aging behavior." Thesis, Troyes, 2016. http://www.theses.fr/2016TROY0015/document.
Повний текст джерелаАнотація:
Depuis quelques années les matériaux composites à base de fibres naturelles sont de plus en plus utilisés pour les nouvelles performances qu’ils proposent. C’est surtout au niveau des fibres naturelles que de nouvelles propriétés sont proposées. Dans ce travail, nous nous sommes essentiellement intéressés aux fibres naturelles de chanvre. Ces fibres sont déjà fortement utilisées dans l’automobile et la construction. En Europe, ces fibres sont produites principalement en France et plus particulièrement dans l’Aube. Pour développer des agro-composites hautes performances, c’est sous la forme de fibres longues et de tissus que nous avons choisi d’orienter ce travail de thèse. Nous avons choisi la thermocompression pour élaborer des plaques avec des tissus de chanvre et une matrice en polypropylène (PP). Ce travail permet de voir l’influence des conditions d’élaboration sur le comportement mécaniques de ces agro-composites. Cette thèse permet aussi de voir l’effet du vieillissement aux UV et à l’Humidité sur les performances de ces matériaux. Enfin une analyse des contraintes résiduelles par la méthode du trou incrémental permet de voir leurs effets sur ces agro-matériauxIn recent years composite materials based on natural fibers are more and more used for their new performances. Natural fibers propose attractive environmental, mechanical and thermal properties.In this work, we are firstly interested in hemp fibers. These fibers are already used in the automotive and construction industry. In Europe, these fibers are produced mainly in France and especially in Aube. To develop agro-composites with high performances, we have focused this thesis on hemp woven. We chose to elaborate the plates with hemp woven and a polypropylene matrix (PP) by compression molding. This work allows us to see the influence of elaboration conditions on the mechanical behavior of these agro-composites. This thesis also allows us to see the effect of aging conditions UV and humidity on the performance of these materials. Finally an analysis of residual stresses determined by the hole drilling method is proposed to see their effects on the agro-materials
6
Betene, Ebanda Fabien. "Etude des propriétés mécaniques et thermiques du plâtre renforcé de fibres végétales tropicales." Thesis, Clermont-Ferrand 2, 2012. http://www.theses.fr/2012CLF22298/document.
Повний текст джерелаАнотація:
Le plâtre est un matériau de grande disponibilité et très connu pour ses qualités : il est favorable à la protection de l’environnement, assez malléable, de faible densité, aux propriétés fonctionnelles remarquables (coupe-feu, isolant thermique, régulateur de l’hygrométrie des enceintes), décoratif, ... Ce qui justifie l’intérêt accordé à ce matériau pour les constructions. Sa grande fragilité préoccupante est à l’origine des travaux de recherches dans le monde entier en vue de son renforcement. Les fibres de verre et de sisal sont les renforts les plus utilisés à ce jour. Le renforcement par des fibres végétales est de plus en plus recherché. La texture micro structurale poreuse du plâtre favorise son caractère d’isolant thermique. Les textures mises en œuvre jusqu’à présent sont limitées à des porosités comprises entre 30 et 55%. La réduction du coût de ce matériau pour une large utilisation est encore possible et souhaitée. Deux leviers sont exploités dans ce travail, notamment un allègement de la masse de plâtre pour augmenter le taux de porosité et un renforcement de la tenue mécanique par incorporation de fibres végétales produites localement. L’objectif de ce travail est d’évaluer les caractéristiques mécaniques, thermiques et hygrométriques d’un matériau constitué de plâtre pris, à grande porosité, renforcé d’une nouvelle fibre végétale : le Rhecktophyllum Camerunense (RC), une fibre des forêts humides équatoriales. La fibre de sisal, d’utilisation connue pour le renforcement du plâtre, sert de référence à des fins de comparaison. Une série d’expérimentations est menée à cet effet. Une caractérisation physico-chimique des constituants est effectuée, des essais mécaniques de traction et de flexion sont effectués sur les constituants et les matériaux composites plâtre/fibres résultants, la cinétique d’adsorption d’humidité par les constituants et le matériau fibreux est suivie. Le comportement thermique des matériaux plâtre et plâtre/fibres est aussi mesuré. Les fibres utilisées, le sisal et le RC, sont à fort taux de cellulose (entre 49 et 78,8%), la fibre de RC est tubulaire avec 35,5% de porosité. Le plâtre est gâché à l’eau déminéralisée à un rapport massique E/P égal à 1 à partir de la poudre de semihydrate β. Sa microstructure cristalline est constituée de cristaux de gypse sous forme d’aiguilles enchevêtrées avec des vides intercristallins. Sur le plan du comportement mécanique, les résultats obtenus révèlent que le plâtre se montre fragile et présente un module d’élasticité en traction de 1,72 GPa, une résistance à la traction de 0,86 MPa et un allongement à la rupture de 1,16%. En flexion trois points, son module d’élasticité est de 0,64 GPa et sa contrainte à la rupture, de 0,13 MPa. La fibre de sisal est raide et fragile. Son module d’élasticité est compris entre 9 et 21 GPa, elle admet un allongement à rupture de 3 à 7%. Par contre, la fibre de RC est assez ductile avec un module d’Young moyen de 0,7 GPa et un allongement à rupture de 24,2%. L’adhésion du plâtre sur les fibres est faible : il adhère plus sur le sisal que sur le RC. Le sisal renforce mieux le plâtre par une augmentation plus sensible du module d’élasticité de 42,5%, contre 16,3% pour le RC, ce dernier lui apportant plutôt une grande ductilité élastique. Les fibres de RC apportent le maximum de renforcement en traction au plâtre lorsqu’elles sont tissées en unidirectionnel et en flexion lorsqu’elles sont uniformément réparties dans le volume suivant la direction longitudinale de la structure. (...)The plaster is a material of high availability and very known for its qualities : it is favourable to the protection of the environment, quite malleable, of low density, its functional properties are remarkable (firewall, thermal insulation, regulator of the hygroscopy of enclosures), decorative, ... What justifies the interest attached to this material for constructions. Its great alarming brittleness is at the origin of the research tasks in the whole world for its strengthening. The glass fibers and sisal are the more used reinforcements to this day. The strengthening by plant fibers is more and more researched. The microstructure of the plaster is porous ; that promotes its heat insulation character. The textures implemented so far are limited to porosities ranging between 30 and 55%. The reduction of cost of this material for a wide use is still possible and desired. Two levers are exploited in this work, in particular a lightening of the plaster weight to increase the proportion of air voids and a reinforcement of the mechanical resistance with locally produced fibers. The objective of this work is to evaluate the mechanical, thermal and hygrometrical characteristics of a material made up of harden plaster, with high porosity, strengthened by a new plant fiber : the Rhecktophyllum Camerunense (RC), a fiber of humid equatorial forests. The sisal fiber, of known use for the strengthening of the plaster, serves as a reference for comparison purposes. A serie of experiments is conducted to this effect. A physicochemical characterization of constituents is performed. Mechanical tests of tensile and of bending are performed on the constituents and the resulting plaster/fiber composite materials. The kinetic adsorption of moisture by the constituents is followed. The thermal behaviour of plaster and plaster/fiber is also measured. The fibers used, sisal and RC are with high rates of cellulose (between 49 and 78.8% ), the fiber of RC is tubular with 35.5 % of porosity. The plaster is dissolved in demineralized water to a mass ratio W/P equals to 1 from the powder of semihydrate β. Its crystalline microstructure is composed of gypsum crystals in the form of needles tangled with the empty intercristallins. As far as the mechanical behavior is concerne, the result reveals that the plaster is weak, its Young’s modulus in tensile is 1.72 GPa, its tensile strength is 0.86 MPa and its elongation at break is 1.16 %. In three points bending test, its modulus of elasticity is 0.64 GPa and its constraint at break is 0.13 MPa. The sisal fiber is stiff and fragile. Its Young’s modulus is between 9 and 21 GPa, it admits an elongation at break of 3 to 7 %. On the other side, the fiber of RC is quite ductile : the means of Young’s module is 7 GPa and the elongation at break is 24.2 %. The adhesion of the plaster on the fiber surface is low : it adheres more on the sisal than on the RC. The sisal strengthened better the plaster with a sensitive increase of the Young’s modulus of 42.5 %, against 16.3 % for the RC. But the RC fiber gives rather high elastic ductility. The fibers of RC deliver maximum capacity in tensile to the plaster when they are woven into unidirectional. They offer high capacity in bending when they are uniformly distributed inside the volume according to the longitudinal direction of the structure. (...)
7
Seghini, Maria Carolina. "Mechanical Analysis and Fibre/Matrix Interface Optimization for Next Generation of Basalt-Plant Fibre Hybrid Composites." Electronic Thesis or Diss., Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2020. http://www.theses.fr/2020ESMA0003.
Повний текст джерелаАнотація:
La prise de conscience mondiale des enjeux environnementaux a conduit à l’émergence de composites«verts», dans lesquels les fibres naturelles sont amenées à remplacer les fibres synthétiques. Ces nouveaux matériaux offrent des alternatives écologiques aux composites synthétiques traditionnels mais sont difficilement utilisables pour des applications semi-structurales ou structurales. Une solution possible à ce problème est le développement des composites hybrides, en combinant ensemble fibres naturelles et synthétiques. Dans ce cadre, l'objectif de cette étude était de développer des composites hybrides à base de fibres de basalte et de lin. Les composites hybrides ont été élaborés par moulage par infusion sous vide avec une matrice époxy. À des fins de comparaison,des composites 100% à fibres de lin et100%à fibres de basalte ont également été produits. Une caractérisation mécanique quasi-statique et dynamique amontré que l'hybridation permet d’obtenir un composite avec des propriétés mécaniques intermédiaires comparées à celles des composites à fibres de lin ou de basalte. Cependant, l’analyse approfondie des dommages a montré la nécessité d'optimiser la qualité d'adhésion de l'interface fibre/matrice afin d'accroître les performances mécaniques des composites hybrides obtenus. Pour cette raison, différents traitements de modification de surface ont été développés et étudiés pour les fibres de lin et de basalte. Un traitement physique par plasma (Plasma Enhanced Chemical Vapor Deposition) a été appliqué aux fibres de lin et de basalte. Les fibres de lin ont également été soumises à deux traitements chimiques utilisant des espèces enzymatiques et du CO2supercritique. Les effets des traitements sur la stabilité thermique, la morphologie et les propriétés mécaniques des fibres de lin et de basalte ont été étudiés. L’adhérence fibre/matrice a été analysée en réalisant des tests de fragmentation sur des composites monofilamentaires. La qualité de l'adhésion entre les fibres et les matrices époxy et vinylester a été évaluée en termes de longueur critique de fragment, de longueur de décohésion interfaciale et de résistance au cisaillement interfacial. La micto-tomographie haute résolution a été utilisée pour analyser les mécanismes d'endommagement lors des tests de fragmentation. Pour les deux types de fibres, les meilleurs résultat sont été obtenus grâce au traitement par plasma. Ce traitement a consisté à déposer un revêtement homogène de tétravinylsilane à la surface des fibres de basalte et de lin, ce qui a permis une augmentation significative de l’adhérence fibre/matrice, ouvrant ainsi la voie à la prochaine génération de composites hybrides plus respectueux de l’environnement et utilisables pour des applications semi-structuralesGlobal awareness of environmental issues has resulted in the emergence of “green” composites, in which natural fibres are used to replace synthetic ones. However, in semi-or structural applications, it can be inconvenient to use composites based on natural fibres. A possible solution to this problem is the development of hybrid composite materials, combining together plies of natural and synthetic fibres. In this framework, the aim of this research project was to develop basalt-flax fibre hybrid composites with a view to obtaining more environmentally friendly composites for semi-structural applications. Hybrid composites were produced through vacuum infusion molding with epoxy matrix.For comparison purposes, 100% flax fibre composites and 100% basalt fibre composites were also manufactured. A quasi-static and dynamic mechanical characterization showed that the hybridization allows the production of a composite with intermediate mechanical performances compared to those possessed by flax and basalt composites. However, the damage analysis has revealed the need to optimize the fibre/matrix interface adhesion quality, in order to increase the mechanical properties of the resulting hybrid composites. For this reason, different surface modification treatments have been specifically designed and investigated for flax and basalt fibres. Flax and basalt fibres were treated by the physical process of Plasma Enhanced Chemical Vapor Deposition. Flax fibres were also subjected to two chemical treatments using enzymatic species and supercritical CO2. The effects of the surface modification treatments on the thermal stability, morphology and mechanical properties of flax and basalt fibres have been investigated. The degree and extent of fibre/matrix adhesion were analyzed by micromechanical fragmentation tests on monofilament composites. The adhesion quality between fibres and both epoxy and vinylester matrices has been assessed in terms of critical fragment length, debonding length and interfacial shear strength. High-resolution μ-CT has been used to support the analysis of the damage mechanisms during fragmentation tests. For both flax and basalt fibres, the best results were obtained after the plasma polymer deposition process. This process was able to produce a homogeneous tetravinylsilane coating on the surface of basalt and flax fibres, which resulted in a significant increase in the fibre/matrix adhesion, thus paving the way for the next generation of more environmentally friendly hybrid composites for semi-structural applications
8
Réquilé, Samuel. "De la plante aux biocomposites : caractérisation des interfaces multiples et étude des paramètres pertinents Exploring the link between flexural behaviour of hemp and flax stems and fiber stiffness Peeling experiments for hemp retting characterization targeting biocomposites Deeper insight into the moisture-induced hygroscopic and mechanical properties of hemp-reinforced biocomposites. Interfacial properties of hemp fiber/epoxy: effect of moisture sorption and induced hygroscopic stresses Propriétés hygroscopiques et mécaniques d'un biocomposite renforcé par des fibres de chanvre." Thesis, Lorient, 2019. http://www.theses.fr/2019LORIS529.
Повний текст джерелаАнотація:
Les préoccupations environnementales de l'industrie et les stratégies visant à développer un système économique plus durable suscitent un intérêt croissant pour la recherche dans le domaine des biocomposites. Le fort caractère polaire et hydrophile des fibres végétales entraîne, lors de leur utilisation comme renfort, une complexité de mise en œuvre et des limites en termes de transfert de charge à l’interface fibre/matrice. Ces verrous pour le développement des biocomposites sont les lignes directrices de ce travail de thèse s'inspirant de la présence des interfaces au sein des tiges de chanvre. L’évolution progressive de la microstructure et des propriétés mécaniques est cruciale pour l'intégrité et le fonctionnement de la tige à travers des régions de transition. Ces interfaces, potentiels maillons faibles de la structure, sont étudiées en appliquant un processus de rouissage impactant la microstructure interne et la cohésion tissulaire. Des tiges aux fibres élémentaires, l'étude du comportement mécanique des systèmes naturels est une source d’inspiration pour un transfert des principes fondamentaux des biocomposites. Visant à accroître la compréhension de l'effet de l'humidité présente dans l’environnement lors des utilisations composites, l’analyse des propriétés hygro-mécanique permet de mettre en évidence des performances optimales de composites unidirectionnels de part un effet bénéfique de la sorption d’eau. Des études à l'échelle microscopique ont permis d’attribuer une contribution importante du comportement hygroscopique aux performances de l'interface fibre/matrice par la création de contraintes résiduelles et de mécanismes d'adhésion capillaire. Généralement décrite comme un inconvénient, ce travail de recherche montre que la sensibilité à l'eau des fibres végétales ainsi que la sorption de vapeur d’eau dans un biocomposite pourraient favoriser le transfert de charge et être bénéfiques pour leurs performances mécaniquesIndustry environmental concerns and strategies to become part of a more sustainable economic system, leads to a growing interest in research on biocomposite. The strong polar and hydrophilic nature of plant fibers leads, when used as a reinforcement, to a complexity of biocomposite manufacturing and limits in terms of load transfer at the fiber/matrix interface. These major locks (fiber polarity and moisture sensitivity) for biocomposites development are the guidelines of this thesis work taking its inspiration in the design of hemp stem tissue interfaces. The multi-scale evolution of gradient microstructure and internal mechanics is crucial for the integrity and functioning of the stem through smooth transitions regions. These potential weak interfaces are investigated by applying a retting process that affect the stem internal microstructure and tissue cohesion. From the stems of agricultural crops to the hierarchical elementary fibers, studying the mechanical behavior of natural systems may serve as inspiration for a biomimetic transfer of the fundamental principles to fiber-reinforced composites. Aimed at increasing the understanding of the effect of moisture present during composite use, hygro-mechanical coupling highlights an optimum in hemp fibre-based unidirectional composites performances from a beneficial effect of moisture sorption. Deeper analysis at the micro-scale attributed a significant contribution of this hygroscopic behavior to fiber/matrix interface performances through the creation of residual stresses and capillary adhesion mechanisms. Generally described in the literature as a drawback, this research demonstrates that water sensitivity of plant fibers and moisture sorption in biocomposite could promote load transfer and be beneficial for their performance
9
Cho, Baik-Soon. "The in-plane shear properties of pultruded materials." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/21291.
Повний текст джерела
10
Sparnins, Edgars. "Mechanical properties of flax fibers and their composites." Doctoral thesis, Luleå, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26640.
Повний текст джерелаАнотація:
Flax fibers, along with a number of other natural fibers, are being considered as an environmentally friendlier alternative of synthetic fibers in fiber-reinforced polymer composites. A common feature of natural fibers is a much higher variability of mechanical properties. This necessitates study of the flax fiber strength distribution and efficient experimental methods for its determination. Elementary flax fibers of different gauge lengths are tested by single fiber tension in order to obtain the stress-strain response and strength and failure strain distributions. The applicability of single fiber fragmentation test for flax fiber failure strain and strength characterization is considered. It is shown that fiber fragmentation test can be used to determine the fiber length effect on mean fiber strength and limit strain. The effect of mechanical damage in the form of kink bands and of diameter variability on the strength of elementary flax fibers is considered. Stiffness and strength under uniaxial tension of flax fiber composites with thermoset and thermoplastic polymer matrices are studied. The applicability of rule of mixtures and orientational averaging based models, developed for short fiber composites, to flax reinforced polymers are evaluated. Both the quasi-static and time dependent mechanical properties of flax fiber/thermoplastic starch based composites are analyzed. The effect of temperature and relative humidity is investigated. It is found that microdamage accumulation in this type of composites is not significant. Results show that the composite elastic modulus and failure stress are linearly related to the maximum stress reached by the matrix in tensile tests. Simple material models are suggested to account for the observed nonlinear viscoelasticity and viscoplasticity.Godkänd; 2009; 20091029 (edgspa); DISPUTATION Ämnesområde: Polymera konstruktionsmaterial/Polymeric Composite Materials Opponent: Docent Kristofer Gamstedt, Kungliga Tekniska Högskolan, Stockholm Ordförande: Docent Roberts Joffe, Luleå tekniska universitet Tid: Onsdag den 9 december 2009, kl 10.00 Plats: E 231, Luleå tekniska universitet
Книги з теми "Plant fibers Mechanical properties"
1
Blewett, Jennifer Mary. Micromanipulation of plant cell mechanical properties. Birmingham: University of Birmingham, 2000.
Знайти повний текст джерела
2
Physical properties of plant and animal materials: Structure, physical characteristics, and mechanical properties. 2nd ed. New York: Gordon and Breach, 1986.
Знайти повний текст джерела
3
England), Textile Institute (Manchester, ed. Handbook of tensile properties of textile and technical fibres. Cambridge, UK: Woodhead Publishing in association with the Textile Institute, 2009.
Знайти повний текст джерела
4
Fourné, Franz. Synthetic fibers: Machines and equipment, manufacture, properties : handbook for plant engineering, machine design, and operation. Cincinnati, OH: Hanser/Gardner Publications, 1998.
Знайти повний текст джерела
5
Interface Engineering of Natural Fibre Composites for Maximum Performance. Oxford: Woodhead, 2011.
Знайти повний текст джерела
6
Feughelman, Max. Mechanical properties and structure of alpha-keratin fibres: Wool, human hair and related fibres. Sydney: UNSW Press, 1997.
Знайти повний текст джерела
7
Feughelman, Max. Mechanical properties and structure of alpha-keratin fibres: Wool, human hair, and related fibres. Sydney: UNSW Press, 1997.
Знайти повний текст джерела
8
Mechanical properties and structure of alpha-keratin fibres: Wool, human hair and related fibres. Sydney: UNSW Press, 1997.
Знайти повний текст джерела
9
Synthetic fibers: Machines and equipment, manufacture, properties : handbook for plant engineering, machine design, and operation. Munich: Hanser, 1999.
Знайти повний текст джерела
10
Persson, Sverker. Mechanics of cutting plant material. St. Joseph, Mich., USA: American Society of Agricultural Engineers, 1987.
Знайти повний текст джерелаЧастини книг з теми "Plant fibers Mechanical properties"
1
Li, Yan, and Qian Li. "Mechanical Properties of Plant Fiber Reinforced Composites." In Plant Fiber Reinforced Composites, 101–41. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-5162-6_5.
Повний текст джерела
2
Müssig, Jürg, Holger Fischer, Nina Graupner, and Axel Drieling. "Testing Methods for Measuring Physical and Mechanical Fibre Properties (Plant and Animal Fibres)." In Industrial Applications of Natural Fibres, 267–309. Chichester, UK: John Wiley & Sons, Ltd, 2010. http://dx.doi.org/10.1002/9780470660324.ch13.
Повний текст джерела
3
Le Guen, Marie-Joo, Roger H. Newman, Alan Fernyhough, Stefan J. Hill, and Mark P. Staiger. "Correlations Between the Physiochemical Characteristics of Plant Fibres and Their Mechanical Properties." In RILEM Bookseries, 35–47. Dordrecht: Springer Netherlands, 2016. http://dx.doi.org/10.1007/978-94-017-7515-1_3.
Повний текст джерела
4
Olehile, Kaelo, and Vuyo Terrence Hashe. "An Investigative Study on Production of a Composite Novel Plant Fibre: Mechanical Properties Comparison." In Lecture Notes in Mechanical Engineering, 573–82. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-1910-9_47.
Повний текст джерела
5
Cakmak, Hulya, and Ece Sogut. "Functional Biobased Composite Polymers for Food Packaging Applications." In Reactive and Functional Polymers Volume One, 95–136. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-43403-8_6.
Повний текст джерелаАнотація:
AbstractBiobased polymers are of great interest due to the release of tension on non-renewable petroleum-based polymers for environmental concerns. However, biobased polymers usually have poor mechanical and barrier properties when used as the main component of coatings and films, but they can be improved by adding nanoscale reinforcing agents (nanoparticles - NPs or fillers), thus forming nanocomposites. The nano-sized components have a larger surface area that favors the filler-matrix interactions and the resulting material yield. For example, natural fibers from renewable plants could be used to improve the mechanical strength of the biobased composites. In addition to the mechanical properties, the optical, thermal and barrier properties are mainly effective on the selection of type or the ratio of biobased components. Biobased nanocomposites are one of the best alternatives to conventional polymer composites due to their low density, transparency, better surface properties and biodegradability, even with low filler contents. In addition, these biomaterials are also incorporated into composite films as nano-sized bio-fillers for the reinforcement or as carriers of some bioactive compounds. Therefore, nanostructures may provide antimicrobial properties, oxygen scavenging ability, enzyme immobilization or act as a temperature or oxygen sensor. The promising result of biobased functional polymer nanocomposites is shelf life extension of foods, and continuous improvements will face the future challenges. This chapter will focus on biobased materials used in nanocomposite polymers with their functional properties for food packaging applications.
6
Alemyayehu, Samrawit, Yohannes Regassa, Bisrat Yoseph, and Hirpa G. Lemu. "Mechanical Properties Characterization of Water Hyacinth (“Emboch”) Plant for Use as Fiber Reinforced Polymer Composite." In Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering, 482–92. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-80618-7_33.
Повний текст джерела
7
Dresselhaus, Mildred S., Gene Dresselhaus, Ko Sugihara, Ian L. Spain, and Harris A. Goldberg. "Mechanical Properties." In Graphite Fibers and Filaments, 120–52. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-83379-3_6.
Повний текст джерела
8
Mitchell, T. A. "Methods Used in Monitoring and Controlling the Quality of Bread with Particular Reference to the Mechanical Dough Development Process." In Plant Fibers, 313–31. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-83349-6_17.
Повний текст джерела
9
Lee, C. H., A. Khalina, S. H. Lee, F. N. M. Padzil, and Z. M. A. Ainun. "Physical, Morphological, Structural, Thermal and Mechanical Properties of Pineapple Leaf Fibers." In Pineapple Leaf Fibers, 91–121. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-1416-6_6.
Повний текст джерела
10
Mukesh and S. S. Godara. "Comparative Study of Mechanical Properties of Natural Fibers." In Lecture Notes in Mechanical Engineering, 441–48. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-7779-6_38.
Повний текст джерелаТези доповідей конференцій з теми "Plant fibers Mechanical properties"
1
Nayeb Hashemi, Hamid, Gongdai Liu, Ashkan Vaziri, Masoud Olia, and Ranajay Ghosh. "Mechanical Properties of Biomimetic Leaf Composite." In ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-65503.
Повний текст джерелаАнотація:
In this paper, we mimic the venous morphology of a typical plant leaf into a fiber composite structure where the veins are replaced by stiff fibers and the rest of the leaf is idealized as an elastic perfectly plastic polymeric matrix. The variegated venations found in nature are idealized into three principal fibers — the central mid-fiber corresponding to the mid-rib, straight parallel secondary fibers attached to the mid-fiber representing the secondary veins and then another set of parallel fibers emanating from the secondary fibers mimicking the tertiary veins of a typical leaf. The tertiary fibers do not interconnect the secondary fibers in our present study. We carry out finite element (FE) based computational investigation of the mechanical properties such as Young’s moduli, Poisson’s ratio and yield stress under uniaxial loading of the resultant composite structures and study the effect of different fiber architectures. To this end, we use two broad types of architectures both having similar central main fiber but differing in either having only secondary fibers or additional tertiary fibers. The fiber and matrix volume fractions are kept constant and a comparative parametric study is carried out by varying the inclination of the secondary fibers. We find significant effect of fiber inclination on the overall mechanical properties of the composites with higher fiber angles transitioning the composite increasingly into a matrix-dominated response. We also find that in general, composites with only secondary fibers are stiffer with closed cell architecture of the secondary fibers. The closed cell architecture also arrested the yield stress decrease and Poisson’s ratio increase at higher fiber angles thereby mitigating the transition into the matrix dominated mode. The addition of tertiary fibers also had a pronounced effect in arresting this transition into the matrix dominated mode. However, it was found that indiscriminate addition of tertiary fibers may not provide desired additional stiffness for fixed volume fraction of constituents. In conclusion, introducing a leaf-mimicking topology in fiber architecture can provide significant additional degrees of tunability in design of these composite structures.
2
SINGHAL, ANSHUL, AMY LANGHORST, MIHAELA BANU, and ALAN TAUB. "EFFECT OF ENZYMATIC RETTING CONDITIONS ON THE DIAMETER AND MECHANICAL PROPERTIES OF FLAX FIBERS." In Proceedings for the American Society for Composites-Thirty Seventh Technical Conference. Destech Publications, Inc., 2022. http://dx.doi.org/10.12783/asc37/36478.
Повний текст джерелаАнотація:
The current industrial method of extracting natural plant fibers, originally intended for their textile use, can degrade the inherent mechanical properties, making them difficult to replace e-glass fibers for reinforcement in polymer composites. Microorganisms during the initial dew/field retting step of fiber extraction process not only degrades the fiber-stem interphase bond constituting primarily pectin and lignin, but also degrades the structural components of the fiber such as cellulose, resulting in non-uniform technical fibers with poor mechanical properties. Also, current single fiber testing standards used for mechanical properties characterization of these fibers are suitable for assessing homogenous and uniform fiber properties correctly, which is not the case in natural fibers. In this study, the flax stems were treated with Pectinase Ultra SPL enzyme targeted to degrade the pectin bonds between the fibers and plant stem, without affecting the structural component cellulose. In this study, the size of technical fibers hand extracted from dew and enzyme retted flax are compared. The hand extracted enzyme retted stem fibers showed more uniform, finer diameters resulting in better tensile properties when compared with dew/field retted stem fibers. The improved properties are related to the diameter effect in which as the area of these fibers is reduced, the reduction of defects during the fiber extraction.
3
Gund, Mahesh, and R. T. Vyavahare. "Finite Element Analysis of Ply Orientation Effect on Mechanical Properties of Hybrid Composite Material." In National Conference on Relevance of Engineering and Science for Environment and Society. AIJR Publisher, 2021. http://dx.doi.org/10.21467/proceedings.118.27.
Повний текст джерелаАнотація:
In recent years, composite material is used as an alternative material for materials like metal, wood, etc. due to low in weight, strength to weight ratio and stiffness properties. Natural fibers like coir fiber, palm fiber, jute fiber, banana plant fiber, etc have low cost, easy availability and less harmful to human body. Also, carbon fiber having various properties such as high strength to weight ratio, rigidity, good tensile strength, fatigue resistance, fire resistance/not flammable, high thermal conductivity. This research work aims to find out the mechanical properties of Carbon fiber, Coir fiber and Epoxy composite material with different ply orientations angles by using FEA software Ansys APDL R15.0.
4
Friedrich Munder and Christian Furll. "Effective Processing of Bast Fiber Plants and Mechanical Properties of the Fibers." In 2004, Ottawa, Canada August 1 - 4, 2004. St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2004. http://dx.doi.org/10.13031/2013.16960.
Повний текст джерела
5
SINGHAL, ANSHUL, AMY LANGHORST, ANKUSH BANSAL, MIHAELA BANU, and ALAN TAUB. "OPTIMIZATION OF RETTING AND EXTRACTION THROUGH CONSTITUTIVE MATERIAL MODELLING OF PLANT STEMS FOR VARIABILITY REDUCTION IN EXTRACTED NATURAL FIBERS." In Thirty-sixth Technical Conference. Destech Publications, Inc., 2021. http://dx.doi.org/10.12783/asc36/35867.
Повний текст джерелаАнотація:
Natural plant fibers compared to glass fibers can provide a cost effective, lightweight and carbon negative reinforcement for polymer composites. However, the current commercial fiber extraction process induces defects including middle lamellae weakening during retting and kink bands during mechanical working. This leads to high variability in mechanical properties, making these fibers less favorable for structural applications at industrial scale. The aim of current research is to reduce this variability by studying the underlying mechanisms of natural fiber extraction to minimize fiber damage occurring at various steps in the process. In this study, flax stems were retted using the conventional dew/field and lab scale controlled enzymatic retting. The hand decorticated fibers from both methods were compared and enzymatic retting showed promising results in producing fine and uniform fibers as compared to fibers extracted by dew retting. To establish the constitutive parameters of the fibers for Finite Element Modeling (FEM), single retted flax stems were compression tested using a Texture Analyzer. This data can serve as the basis for modeling the mechanical deformation of plant stems passing through breaking rollers which is the first step in extraction after retting. The goal is to optimize the roller design and process conditions required to extract fibers with minimal damage and variability.
6
Gnanasundar, V. "Mechanical Properties of Fiber Reinforced Concrete by using Sisal Fiber with M-Sand as Fine Aggregate." In Sustainable Materials and Smart Practices. Materials Research Forum LLC, 2022. http://dx.doi.org/10.21741/9781644901953-10.
Повний текст джерелаАнотація:
Abstract. Conventional concrete has a low tensile strength, constrained ductility and little protection from crack propagation. The inward miniaturized scale of cracks, prompting weak disappointment of concrete. Investigations have been carried out in many countries on various mechanical properties, physical performance and durability of cement-based matrices reinforced with naturally occurring fibers including sisal, coconut, jute, bamboo, and wood fibers. Raised natural mindfulness and an expanding worry with an unnatural weather change have invigorated the search for materials that can supplant traditional engineered fiber. Characteristic fiber, for example, sisal strands show up as one of the great options since they are accessible in sinewy structure and can be separated from plant leaves, stalk, and products of the soil at exceptionally low expenses. In this work, the impact of sisal strands on the quality of cement for M25 evaluation has been examined by shifting the level of filaments in concrete. Fiber substance were shifted by 0.05%, 0.10%, 0.15%, 0.20%, 0.25%, 0.30%, 0.35% and 0.40% by volume of cement. Cubes, Cylinder and Prism were cast to assess the Compressive, Split Tensile and Flexural Strength test. Every one of the samples was tested for a time of 28 days curing. The results of fiber reinforced concrete for 28 days curing with a varied percentage of fiber were studied and it has been found that there is significant strength improvement with addition of sisal fiber in concrete.
7
Remillat, C. "Elastic Properties of Composites Based on Tree Root Fibers." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-81031.
Повний текст джерелаАнотація:
The in plane mechanical properties of composites based on fibres which shape is that of a tree root has been investigated. The number of fibrils as well as the angle between them have been shown to influence significantly the effective properties of the composite. It can be shown that there is an optimal number of fibrils and an optimal angle for which the stiffness of the material is maximum
8
McClay, Jessica N., Peter Joyce, and Andrew N. Smith. "Determination of the Directional Dependent In-Plane Thermal Conductivity of K63B12 Pitch-Fiber/Epoxy Composite." In ASME 2004 International Mechanical Engineering Congress and Exposition. ASMEDC, 2004. http://dx.doi.org/10.1115/imece2004-60001.
Повний текст джерелаАнотація:
Measurements of the in-plane thermal conductivity and the directional dependence of Mitsubishi K63B12 pitch-fiber/Epoxy composite from Newport Composites are reported. This composite is being explored for use in the Avanced Seal Delivery System for effective thermal management. The thermal conductivity was measured using a steady state technique. The experimental results were then compared to a model of the thermal conductivity based on the direction of the fibers. These estimates are based on the properties of the constituent materials and volume of fibers in the sample. Therefore the density and the fiber volume fraction were experimentally measured. The thermal conductivity is clearly greatest in the direction of the fibers and decreases as the fibers are rotated off axis. In the case of pitch fiber composite materials, the contribution of the fibers to the thermal conductivity dominates. The experimental data clearly followed the correct trends; however, the measured values were 25% to 35% lower than predicted.
9
Hosseini, Nassibeh, Chad A. Ulven, Fardad Azarmi, Dean C. Webster, and Thomas J. Nelson. "Utilization of Flax Fibers and Glass Fibers in a Bio-Based Resin." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-39393.
Повний текст джерелаАнотація:
A novel highly functional plant oil-based polyols, Methoxylated Sucrose Soyate Polyols (MSSP), were cross-linked with isocyanate to formulate MSSP-based polyurethane (PU) thermosets. The degree of cure or conversion was studied using differential scanning calorimetry (DSC). Compression molding process was used to make composite panels out of MSSP-based polyurethane and flax fiber reinforcement of about 50 vol %. The MSSP-based PU resin reinforced with 50 vol % unidirectional E-glass fiber mats was tested as a reference. The composites were cured at 150°C for 60 minutes. Properties of the MSSP-based PU thermosets and its corresponding flax/glass-fiber reinforced thermoset composites were assessed by tensile strength and modulus, flexural strength and modulus, interlaminar shear strength (ILSS), nanoindentation test, and impact strength. Specific tensile modulus and strength of the flax fiber composites were found to compare with those of glass/MSSP-based PU. The glass/MSSP-based PU composite exhibited superior mechanical properties compared to both bio-based and petroleum-based composites used in previous studies. Compared to soybean oil based composites used in previous studies, bio-based composites based on MSSP showed 70 % and 101 % increase in flexural strength and modulus respectively, 102 % and 93 % increase in tensile strength and modulus respectively, and 56 % increase in ILSS. Compared to petroleum-based PU/glass composites used in previous studies, bio-based composites based on MSSP showed 60 % and 40 % increase in flexural strength and modulus respectively, 102 % and 78 % increase in tensile strength and modulus respectively, 50 % increase in ILSS. Higher mechanical properties in MSSP-based PU composites can be attributed to high functionality, rigid and compact chemical structures of MSSP oligomers in polyol resin.
10
LANGHORST, AMY, ANSHUL SINGHAL, DEBORAH MIELEWSKI, MIHAELA BANU, and ALAN TAUB. "NANOPARTICLE MODIFICATION OF NATURAL FIBERS FOR STRUCTURAL COMPOSITES." In Thirty-sixth Technical Conference. Destech Publications, Inc., 2021. http://dx.doi.org/10.12783/asc36/35868.
Повний текст джерелаАнотація:
Natural fibers are a lightweight, carbon negative alternative to synthetic reinforcing agents in polymer composites. However, natural fibers typically exhibit lower mechanical performance than glass fibers due to weak interfacial adhesion between plant cells in the fiber and damage to the fibers during extraction from a plant stem. However, improvement of natural fiber mechanical performance could enable their wide-scale incorporation in structural composite applications, significantly reducing composite weight and carbon footprint. This study seeks to develop a novel, cost-effective method to significantly improve natural fiber stiffness via repair of damage caused by extraction and/ or stiffening of the weak cellular interfaces within a natural fiber. Supercritical fluids have been shown to be capable of swelling and plasticizing amorphous polymers, increasing additive absorption. In this work. supercritical-carbon dioxide (scCO2) was used as a solvent to assist with infusion of nanoparticles into flax fibers at pressures ranging from 1200-4000psi. Fiber analysis with Plasma Focused Ion Beam-Scanning Electron Microscopy (PFIB-SEM) showed that nanoparticles were capable of penetrating and bridging openings between cells, suggesting the ability for nanoparticle treatment to assist with crack repair. Additionally, treated fibers contained uniform surface coatings of nanoparticles, potentially reducing fiber porosity and modifying interfacial properties when embedded in a polymer matrix. Overall, this method of nanoparticle reinforcement of natural fibers could enable development of high-performance lightweight, low-carbon footprint composites for transportation or industrial applications.
Звіти організацій з теми "Plant fibers Mechanical properties"
1
Petit, Sylvain, Joannie Chin, Amanda Forster, Michael Riley, and Kirk Rice. Effect of artificial perspiration and cleaning chemicals on mechanical and chemical properties of ballistic fibers. Gaithersburg, MD: National Institute of Standards and Technology, 2008. http://dx.doi.org/10.6028/nist.ir.7494.
Повний текст джерела
2
Singh, J. P., D. Singh, and R. A. Lowden. Effect of fiber coating on mechanical properties of Nicalon fibers and Nicalon-fiber/SiC matrix composites. Office of Scientific and Technical Information (OSTI), December 1993. http://dx.doi.org/10.2172/10116281.
Повний текст джерела
3
Ragalwar, Ketan, William Heard, Brett Williams, Dhanendra Kumar, and Ravi Ranade. On enhancing the mechanical behavior of ultra-high performance concrete through multi-scale fiber reinforcement. Engineer Research and Development Center (U.S.), September 2021. http://dx.doi.org/10.21079/11681/41940.
Повний текст джерелаАнотація:
Steel fibers are typically used in ultra-high performance concretes (UHPC) to impart flexural ductility and increase fracture toughness. However, the mechanical properties of the steel fibers are underutilized in UHPC, as evidenced by the fact that most of the steel fibers pull out of a UHPC matrix largely undamaged during tensile or flexural tests. This research aims to improve the bond between steel fibers and a UHPC matrix by using steel wool. The underlying mechanism for fiber-matrix bond improvement is the reinforcement of the matrix tunnel, surrounding the steel fibers, by steel wool. Single fiber pullout tests were performed to quantify the effect of steel wool content in UHPC on the fiber-matrix bond. Microscopic observations of pulled-out fibers were used to investigate the fiber-matrix interface. Compared to the control UHPC mixture with no steel wool, significant improvement in the flexural behavior was observed in the UHPC mixtures with steel wool. Thus, the addition of steel wool in steel fiber-reinforced UHPC provides multi-scale reinforcement that leads to significant improvement in fiber-matrix bond and mechanical properties of UHPC.
4
Sadek, Fahim, Travis Thonstad, Sorin Marcu, Jonathan M. Weigand, Timothy J. Barrett, Hai S. Lew, Long T. Phan, and Adam L. Pintar. Structural Performance of Nuclear Power Plant Concrete Structures Affected by Alkali-Silica Reaction (ASR) Task 1: Assessing In-Situ Mechanical Properties of ASR-Affected Concrete. National Institute of Standards and Technology, February 2021. http://dx.doi.org/10.6028/nist.tn.2121.
Повний текст джерела
5
Tzfira, Tzvi, Michael Elbaum, and Sharon Wolf. DNA transfer by Agrobacterium: a cooperative interaction of ssDNA, virulence proteins, and plant host factors. United States Department of Agriculture, December 2005. http://dx.doi.org/10.32747/2005.7695881.bard.
Повний текст джерелаАнотація:
Agrobacteriumtumefaciensmediates genetic transformation of plants. The possibility of exchanging the natural genes for other DNA has led to Agrobacterium’s emergence as the primary vector for genetic modification of plants. The similarity among eukaryotic mechanisms of nuclear import also suggests use of its active elements as media for non-viral genetic therapy in animals. These considerations motivate the present study of the process that carries DNA of bacterial origin into the host nucleus. The infective pathway of Agrobacterium involves excision of a single-stranded DNA molecule (T-strand) from the bacterial tumor-inducing plasmid. This transferred DNA (T-DNA) travels to the host cell cytoplasm along with two virulence proteins, VirD2 and VirE2, through a specific bacteriumplant channel(s). Little is known about the precise structure and composition of the resulting complex within the host cell and even less is known about the mechanism of its nuclear import and integration into the host cell genome. In the present proposal we combined the expertise of the US and Israeli labs and revealed many of the biophysical and biological properties of the genetic transformation process, thus enhancing our understanding of the processes leading to nuclear import and integration of the Agrobacterium T-DNA. Specifically, we sought to: I. Elucidate the interaction of the T-strand with its chaperones. II. Analyzing the three-dimensional structure of the T-complex and its chaperones in vitro. III. Analyze kinetics of T-complex formation and T-complex nuclear import. During the past three years we accomplished our goals and made the following major discoveries: (1) Resolved the VirE2-ssDNA three-dimensional structure. (2) Characterized VirE2-ssDNA assembly and aggregation, along with regulation by VirE1. (3) Studied VirE2-ssDNA nuclear import by electron tomography. (4) Showed that T-DNA integrates via double-stranded (ds) intermediates. (5) Identified that Arabidopsis Ku80 interacts with dsT-DNA intermediates and is essential for T-DNA integration. (6) Found a role of targeted proteolysis in T-DNA uncoating. Our research provide significant physical, molecular, and structural insights into the Tcomplex structure and composition, the effect of host receptors on its nuclear import, the mechanism of T-DNA nuclear import, proteolysis and integration in host cells. Understanding the mechanical and molecular basis for T-DNA nuclear import and integration is an essential key for the development of new strategies for genetic transformation of recalcitrant plant species. Thus, the knowledge gained in this study can potentially be applied to enhance the transformation process by interfering with key steps of the transformation process (i.e. nuclear import, proteolysis and integration). Finally, in addition to the study of Agrobacterium-host interaction, our research also revealed some fundamental insights into basic cellular mechanisms of nuclear import, targeted proteolysis, protein-DNA interactions and DNA repair.
6
Snyder, Victor A., Dani Or, Amos Hadas, and S. Assouline. Characterization of Post-Tillage Soil Fragmentation and Rejoining Affecting Soil Pore Space Evolution and Transport Properties. United States Department of Agriculture, April 2002. http://dx.doi.org/10.32747/2002.7580670.bard.
Повний текст джерелаАнотація:
Tillage modifies soil structure, altering conditions for plant growth and transport processes through the soil. However, the resulting loose structure is unstable and susceptible to collapse due to aggregate fragmentation during wetting and drying cycles, and coalescense of moist aggregates by internal capillary forces and external compactive stresses. Presently, limited understanding of these complex processes often leads to consideration of the soil plow layer as a static porous medium. With the purpose of filling some of this knowledge gap, the objectives of this Project were to: 1) Identify and quantify the major factors causing breakdown of primary soil fragments produced by tillage into smaller secondary fragments; 2) Identify and quantify the. physical processes involved in the coalescence of primary and secondary fragments and surfaces of weakness; 3) Measure temporal changes in pore-size distributions and hydraulic properties of reconstructed aggregate beds as a function of specified initial conditions and wetting/drying events; and 4) Construct a process-based model of post-tillage changes in soil structural and hydraulic properties of the plow layer and validate it against field experiments. A dynamic theory of capillary-driven plastic deformation of adjoining aggregates was developed, where instantaneous rate of change in geometry of aggregates and inter-aggregate pores was related to current geometry of the solid-gas-liquid system and measured soil rheological functions. The theory and supporting data showed that consolidation of aggregate beds is largely an event-driven process, restricted to a fairly narrow range of soil water contents where capillary suction is great enough to generate coalescence but where soil mechanical strength is still low enough to allow plastic deforn1ation of aggregates. The theory was also used to explain effects of transient external loading on compaction of aggregate beds. A stochastic forInalism was developed for modeling soil pore space evolution, based on the Fokker Planck equation (FPE). Analytical solutions for the FPE were developed, with parameters which can be measured empirically or related to the mechanistic aggregate deformation model. Pre-existing results from field experiments were used to illustrate how the FPE formalism can be applied to field data. Fragmentation of soil clods after tillage was observed to be an event-driven (as opposed to continuous) process that occurred only during wetting, and only as clods approached the saturation point. The major mechanism of fragmentation of large aggregates seemed to be differential soil swelling behind the wetting front. Aggregate "explosion" due to air entrapment seemed limited to small aggregates wetted simultaneously over their entire surface. Breakdown of large aggregates from 11 clay soils during successive wetting and drying cycles produced fragment size distributions which differed primarily by a scale factor l (essentially equivalent to the Van Bavel mean weight diameter), so that evolution of fragment size distributions could be modeled in terms of changes in l. For a given number of wetting and drying cycles, l decreased systematically with increasing plasticity index. When air-dry soil clods were slightly weakened by a single wetting event, and then allowed to "age" for six weeks at constant high water content, drop-shatter resistance in aged relative to non-aged clods was found to increase in proportion to plasticity index. This seemed consistent with the rheological model, which predicts faster plastic coalescence around small voids and sharp cracks (with resulting soil strengthening) in soils with low resistance to plastic yield and flow. A new theory of crack growth in "idealized" elastoplastic materials was formulated, with potential application to soil fracture phenomena. The theory was preliminarily (and successfully) tested using carbon steel, a ductile material which closely approximates ideal elastoplastic behavior, and for which the necessary fracture data existed in the literature.
7
Huang, Cihang, Yen-Fang Su, and Na Lu. Self-Healing Cementitious Composites (SHCC) with Ultrahigh Ductility for Pavement and Bridge Construction. Purdue University, 2021. http://dx.doi.org/10.5703/1288284317403.
Повний текст джерелаАнотація:
Cracks and their formations in concrete structures have been a common and long-lived problem, mainly due to the intrinsic brittleness of the concrete. Concrete structures, such as rigid pavement and bridge decks, are prone to deformations and deteriorations caused by shrinkage, temperature fluctuation, and traffic load, which can affect their service life. Rehabilitation of concrete structures is expensive and challenging—not only from maintenance viewpoints but also because they cannot be used for services during maintenance. It is critical to significantly improve the ductility of concrete to overcome such issues and to enable better infrastructure quality. To this end, the self-healing cementitious composites (SHCC) investigated in this work could be a promising solution to the aforementioned problems. In this project, the team has designed a series of cementitious composites to investigate their mechanical performances and self-healing abilities. Firstly, various types of fibers were investigated for improving ductility of the designed SHCC. To enhance the self-healing of SHCC, we proposed and examined that the combination of the internal curing method with SHCC mixture design can further improve self-healing performance. Three types of internal curing agents were used on the SHCC mixture design, and their self-healing efficiency was evaluated by multiple destructive and non-destructive tests. Results indicated a significant improvement in the self-healing capacity with the incorporation of internal curing agents such as zeolite and lightweight aggregate. To control the fiber distribution and workability of the SHCC, the mix design was further adjusted by controlling rheology using different types of viscosity modifiers. The team also explored the feasibility of the incorporation of colloidal nano-silica into the mix design of SHCC. Results suggest that optimum amounts of nano-silica have positive influence on self-healing efficiency and mechanical properties of the SHCC. Better hydration was also achieved by adding the nano-silica. The bonding strength of the SHCC with conventional concrete was also improved. At last, a standardized mixing procedure for the large scale SHCC was drafted and proposed.
8
STUDY ON MECHANICAL PROPERTIES OF STAINLESS STEEL PLATE SHEAR WALL STRENGTHENED BY CORRUGATED FRP. The Hong Kong Institute of Steel Construction, August 2022. http://dx.doi.org/10.18057/icass2020.p.305.
Повний текст джерелаАнотація:
In this paper, the mechanical properties of stainless steel plate shear walls reinforced with fiber reinforced polymer (FRP) of corrugated sections were studied. Two scaled FRP-stainless steel plate shear wall specimens were designed and subjected to the monotonic horizontal load. FRPs in the form of corrugated and flat sections were respectively used to reinforce the embedded steel plates of the steel plate shear wall. The test results show that the failure mode of flat FRP reinforced steel plate shear wall is mainly the peeling of the FRP, while the failure mode of corrugated FRP reinforced steel plate shear wall is mainly the tensile fracture of the FRP. The out-of-plane deformation of steel plate reinforced with corrugated FRP can be effectively restrained. The maximum bearing capacity of the two specimens is 97.96 kN and 106.32 kN respectively. The yield load of the specimen with corrugated FRP is increased by 16.5%, the ultimate bearing capacity is increased by 9.3% and the stiffness is increased by 68%.
9
Noise Absorption Behavior of Aluminum Honeycomb Composite. SAE International, September 2020. http://dx.doi.org/10.4271/2020-28-0453.
Повний текст джерелаАнотація:
Natural fibers are one of the major ways to improve environmental pollution. In this study experimental investigation and simulation of honeycomb filled with cotton fabric, wood dust and polyurethane were carried out. This study determines the potential use of cotton fabric, wood dust as good sound absorbers. Automotive industries are looking forward to materials that have good acoustic properties, lightweight, strong and economical. This study provides a better understanding of sound-absorbing material with other mechanical properties. With simulation and experimental results, validation of works provides a wider industrial application for the interior of automotive industries including marine, aviation, railway industry and many more.