Journal articles: 'Impregnated reinforcement'

1

Vlach, Tomáš, Lenka Laiblová, Jakub Řepka, Zuzana Jirkalová, and Petr Hájek. "EXPERIMENTAL VERIFICATION OF IMPREGNATED TEXTILE REINFORCEMENT SPLICING BY OVERLAPPING." Acta Polytechnica CTU Proceedings 22 (July 25, 2019): 128–32. http://dx.doi.org/10.14311/app.2019.22.0128.

Full text

Abstract:

This paper presents an experimental verification of impregnated textile reinforcement splicing by overlapping using tensile test of small textile reinforced concrete slabs before its using in the product. The specimen dimensions were designed 80×360mm and thickness approximately 18 mm. This specimen was reinforced using two pieces of impregnated flat technical fabric from carbon roving and epoxy resin. Two overlap lengths were designed using data from previous cohesion tensile tests and necessary anchoring length. The purpose of this experiment was experimental verification before flat reinforcement splicing by overlapping on the final product – furniture with textile reinforcement. This paper shows possible problems and complications in the anchoring of the textile reinforcements and in splicing by overlapping, the importance of the accuracy reinforcement position in the thin concrete cross-sectional area.

APA, Harvard, Vancouver, ISO, and other styles

2

Hegger, Josef, Christian Kulas, and Michael Horstmann. "Realization of TRC Façades with Impregnated AR-Glass Textiles." Key Engineering Materials 466 (January 2011): 121–30. http://dx.doi.org/10.4028/www.scientific.net/kem.466.121.

Full text

Abstract:

In the last 30 years, façade-panels made of steel-reinforced concrete have become less attractive for architects and clients. Due to the metallic reinforcement, the insufficient concrete covers of former design code generations and hence the material-dependent corrosion, many cases of damage occurred. Using technical textiles for a new composite material, Textile Reinforced Concrete (TRC), it is possible to produce concrete structures which are not vulnerable to corrosion. The presented ventilated large-sized façade elements and self-supporting sandwich panels exemplify the capability of TRC. In the paper, applied materials are characterized and the production process of tailor-made textile reinforcements as well as the load-bearing behavior of the members is described.

APA, Harvard, Vancouver, ISO, and other styles

3

Asgharzadeh, Amir, and Michael Raupach. "Tensile strength of carbon rovings impregnated with different materials under anodic polarization." MATEC Web of Conferences 199 (2018): 11015. http://dx.doi.org/10.1051/matecconf/201819911015.

Full text

Abstract:

Carbon textiles are used more and more as reinforcement in concrete structures. Due to their high durability the concrete covers can be extremely thin compared to traditional steel reinforced concrete, resulting in the possibility to build very thin elements with excellent performance. To improve the properties of the carbon textiles, the rovings are normally impregnated with different types of polymers. Additionally to the use as reinforcement, carbon textiles can also be used as anodes for cathodic protection. However, while first tests have shown, that impregnated carbon rovings are suitable to be used as CP-anodes, it is still not clear under which conditions the new types of anodes are stable or when they start to dissolve. This paper describes investigations on the influence of an anodic polarisation on the tensile strength of different types of impregnated carbon rovings.

APA, Harvard, Vancouver, ISO, and other styles

4

Ghazzawi, Yousof M., Andres F. Osorio, and Michael T. Heitzmann. "Fire performance of continuous glass fibre reinforced polycarbonate composites: The effect of fibre architecture on the fire properties of polycarbonate composites." Journal of Composite Materials 53, no. 12 (October 23, 2018): 1705–15. http://dx.doi.org/10.1177/0021998318808052.

Full text

Abstract:

The fire performance of polycarbonate resin and the role of glass fibre reinforcement in altering the fire performance was investigated. Three different fibre weaves with comparable surface density, plain, twill, and unidirectional glass fabrics, were used as reinforcements. E-glass fabrics were solution-impregnated with polycarbonate/dichloromethyl, laid up, and compression-moulded to consolidate the glass fibre reinforced polycarbonate composite. Cone calorimetry tests with an incident radiant flux of 35 kW/m2 were used to investigate the fire properties of polycarbonate resin and its composites. Results showed that glass fibre reinforcement improves polycarbonate performance by delaying its ignition, decreasing its heat release rate, and lowering the mass loss rate. The three fibre weave types exhibited similar time to ignition. However, unidirectional fibre had a 35% lower peak heat release rate followed when compared to plain and twill weave fibres.

APA, Harvard, Vancouver, ISO, and other styles

5

Obradovic, Vera, Dusica Stojanovic, Aleksandar Kojovic, Irena Zivkovic, Vesna Radojevic, Petar Uskokovic, and Radoslav Aleksic. "Aramid composites impregnated with different reinforcement: Nanofibers, nanoparticles and nanotubes." Zastita materijala 55, no. 4 (2014): 351–61. http://dx.doi.org/10.5937/zasmat1404351o.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Abida, Marwa, Florian Gehring, Jamel Mars, Alexandre Vivet, Fakhreddine Dammak, and Mohamed Haddar. "Effect of hygroscopy on non-impregnated quasi-unidirectional flax reinforcement behaviour." Industrial Crops and Products 128 (February 2019): 315–22. http://dx.doi.org/10.1016/j.indcrop.2018.11.008.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Vasileiou, G., C. Vakouftsis, N. Rogkas, S. Tsolakis, P. Zalimidis, and V. Spitas. "Design and construction of a continuous impregnation apparatus of woven fibres, using non-meshing double-sinusoidal toothed rollers." MATEC Web of Conferences 317 (2020): 01006. http://dx.doi.org/10.1051/matecconf/202031701006.

Full text

Abstract:

Resin-impregnated fibres are extensively used in a variety of industrial applications as is demonstrated in the literature. Resin-fibre impregnation techniques are used in order to create homogeneous macro – materials and to take full advantage of the mechanical properties of the fibrous reinforcement (i.e. carbon, glass, organic or ceramic fibres). However, achieving highly impregnated fibres is proven quite challenging especially in continuous production techniques that are required for large production rates. The main challenge lies in achieving complete impregnation of the tightly arranged fibres mainly referring to the formed yarns containing multiple fibres, sometimes even twisted. This results in partially impregnated materials containing cavities that tend to exhibit inferior mechanical properties compared to the theoretical calculations, which assume fully impregnated materials. These cavities often lead to crack generation, acting as stress concentration sites, resulting in complete failure of the material at macro-level. In this paper a novel technique for continuous production of fully impregnated woven fibres is presented using non – meshing, co – rotating rollers. A laboratory-scale apparatus is designed and described thoroughly in the context of this work. The method resembles pultrusion in the sense that a reinforcement plain fibre mesh (glass) is co–processed with the liquid resin through a pair of co–rotating toothed rollers to produce a continuously reinforced 3D tape. The surface of the rollers is produced from a double-sinusoidal toothed surface (rack) using the Theory of Gearing in three-dimensions, which imposes significant differential sliding of the fibres without differential tension and facilitates fibre wetting. The geometry of the rollers is calculated not to damage the unprocessed fibres, while facilitating local widespreading of the stranded fibres in the three – dimensional space leading to the resin being able to fully penetrate the reinforcing fibre material.

APA, Harvard, Vancouver, ISO, and other styles

8

Pidun, Kevin, and Thomas Gries. "Shaped Textile Reinforcement Elements for Concrete Components." Advanced Materials Research 747 (August 2013): 415–19. http://dx.doi.org/10.4028/www.scientific.net/amr.747.415.

Full text

Abstract:

By now the application of Textile Reinforced Concrete (TRC) for facade constructions can be considered as state of the art. Especially ventilated curtain walls made of TRC and sandwich elements made in combination of TRC-layers and foam cores recently are realized in pilot projects which are predominantly located in Aachen, Germany. The Life funded Insu-Shell façade of the Institute fuer Textiltechnik (ITA) of RWTH Aachen University gives an example of such a pilot project. Furthermore, a pedestrian bridge has been built in Albstadt, Germany. The enormous potential of TRC-applications is shown in these practical projects. All projects have been completed successfully and present good results in terms of the surface quality, the design freedom, the wall thinness and the ecological performance. A networked process chain was aimed at and approached and finally implemented. Apart from this, all these projects incorporating impregnated textile reinforcements reveal unanswered questions regarding production of shaped reinforcement elements, their ability to bear loads and their durability. Particularly the transformation of a 2D-warp-knit fabric to a reinforcement element (textile reinforcement cage) is a challenge, which needs to be addressed further. Since the beginning of 2012 a new transfer project called Shaped textile reinforcement elements for concrete components (T08) within the framework of the Collaborative Research Center 532 `Textile Reinforced Concrete - Development of a new technology` is funded. That challenge is to be solved in the T08 project in cooperation with Institutes from the RWTH Aachen University and industry partners led by the Institute of Structural Concrete of RWTH Aachen University.

APA, Harvard, Vancouver, ISO, and other styles

9

Hatta, Minori, Akikazu Shinya, Harunori Gomi, Pekka K. Vallittu, Eija Säilynoja, and Lippo V. J. Lassila. "Effect of Interpenetrating Polymer Network (IPN) Thermoplastic Resin on Flexural Strength of Fibre-Reinforced Composite and the Penetration of Bonding Resin into Semi-IPN FRC Post." Polymers 13, no. 18 (September 21, 2021): 3200. http://dx.doi.org/10.3390/polym13183200.

Full text

Abstract:

The purpose of this study was to evaluate the effects of interpenetrating polymer network (IPN) thermoplastic resin on the flexural strength of fibre-reinforced composite (FRC) with different IPN polymer compositions. The penetration of bonding resin into semi-IPN FRC posts was also evaluated. The IPN thermoplastic resin used was UDMA-MMA monomer with either PMMA (0.5%, 2%, 5%) or PMMA-copolymer (0.5%, 2%). A no added IPN polymer resin was also made. Mixed resin was impregnated to S- and E-glass fibre rovings. These resins and resin impregnated fibres were used for flexural strength (FS) test. To evaluate the penetration of bonding resin into semi-IPN post, SEM observation was done with various impregnation time and polymerization mehods (hand-light- and oven-cure). The result of FS was recorded from 111.7 MPa (no-IPN polymer/no-fibre-reinforcement) to 543.0 MPa (5% PMMA/S-glass FRC). ANOVA showed that there were significant differences between fibre-reinforcement and no-fibre-reinforcement (p < 0.01) both in S- and E-glass fibre groups, and between 0.5% PMMA and 5% PMMA in the S-glass FRC group. SEM micrographs showed that the penetration layers of bonding resin into hand-light cured semi-IPN posts were different according to impregnation time. Fibre reinforcement is effective to improve flexural strength. The depth of penetration layer of bonding resin into semi-IPN matrix resin was improved when a hand-light cure was used.

APA, Harvard, Vancouver, ISO, and other styles

10

Choi, Sung-Woong, Sung-Ha Kim, Mei-Xian Li, Jeong-Hyeon Yang, and Hyeong-Min Yoo. "Tow Deformation Behaviors in Resin-Impregnated Glass Fibers under Different Flow Rates." Applied Sciences 11, no. 8 (April 16, 2021): 3575. http://dx.doi.org/10.3390/app11083575.

Full text

Abstract:

With the rapid development of high-performance fibers such as carbon, enhanced glass fibers in structural applications, the use of fiber-reinforced composite (FRC) materials has also increased in many areas. Liquid composite molding (LCM) is a widely used manufacturing process in composite manufacturing; however, the rapid impregnation of resin in the reinforcing fibers during processing poses a significant issue. The optimization of resin impregnation is related to tow deformations in the reinforcing fibers. The present study therefore focuses on this tow deformation. The permeability behaviors in double-scale porous media were observed under different flow rates and viscosity conditions to examine the overall tendencies of structural changes in the reinforcement. The permeability results showed hysteresis with increasing and decreasing flow rate conditions of 50–800 mm3/s, indicating structural changes in the reinforcement. The tow behaviors of the double-scale porous media with respect to the thickness and flow rate were investigated in terms of the representative indices of the minor axis (tow thickness) and major axis. The minor axis and major axis of the tow showed decreasing and increasing trends of 2–5% and 2%, respectively, with minimum and maximum values at different positions along the reinforcement, affected by the different hydrodynamic entry lengths. Finally, the deformed tow behavior was observed microscopically to examine the behavior of the tow at different flow rates.

APA, Harvard, Vancouver, ISO, and other styles

11

Vidal-Sallé, Emmanuelle, and Francesco Massi. "Friction Measurement on Dry Fabric for Forming Simulation of Composite Reinforcement." Key Engineering Materials 504-506 (February 2012): 319–24. http://dx.doi.org/10.4028/www.scientific.net/kem.504-506.319.

Full text

Abstract:

Forming processes are highly influenced by all the interface conditions between the tooling and the workpieces. For thermo-mechanical processes like hot forging or cutting processes friction is widely studied for a long time but for composite parts, it is not the case because the problem is not so crucial: forming forces are generally weak enough to allow the part be realized with any forming device; surface quality is not highly affected by the friction conditions; for pre-impregnated fabrics, the viscous or even fluid matrix acts like a lubricant and avoids defects due to sticking between fibre reinforcement and metallic tools. Nevertheless, friction seems to have an important role when precise simulations are expected. Up to now, few studies have been focussed on friction during composite forming processes. The aim of the present study is to make a contribution on that topic for an experimental point of view using an high precision device able to measure small friction forces. The relative fibre orientations can be monitored in order to explore the whole range of geometrical configurations. The final goal is to develop an efficient tool for finite element simulations of dry and pre-impregnated fibre fabrics accounting for the main specificity of fabrics, that is to say their strong anisotropy.

APA, Harvard, Vancouver, ISO, and other styles

12

NISHI, Masato, Tetsushi KABURAGI, Masashi KUROSE, Tei HIRASHIMA, and Tetsusei KURASHIKI. "Forming simulation of thermoplastic pre-impregnated textile reinforcement by finite element method." Transactions of the JSME (in Japanese) 80, no. 820 (2014): SMM0354. http://dx.doi.org/10.1299/transjsme.2014smm0354.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Young, Wen-Bin, and Cheng-Wey Chiu. "Study on Compression Transfer Molding." Journal of Composite Materials 29, no. 16 (November 1995): 2180–91. http://dx.doi.org/10.1177/002199839502901605.

Full text

Abstract:

Resin transfer molding (RTM) finishes the resin impregnation and composite fabrication at the same time. It simplifies the process for composites fabrication and has the advantages of automation, low cost, and versatile design of fiber reinforcement. Therefore, the RTM process is widely used in the architecture, automotive, and aerospace industries. However, in the RTM process, resin must flow through the fiber reinforcement in the planar direction, which, in some cases such as fabrications of large panels, may need a long time for the mold filling. If the part dimension is too large or the fiber permeability is too low, the mold filling process may not be able to complete before the resin gels. Therefore, some modification for the RTM process is necessary in order to reduce the mold filling time. In the compression transfer molding, the mold opens a small gap for the resin to fill in between fiber mats and the mold, and then compresses the fiber reinforcement to be impregnated by the resin in the thickness direction. In this way, since resin is forced into the fiber reinforcements in the thickness direction, the damage of the fibers will be minimized. In addition, the mold filling time will be reduced due to the different flow path of the resin inside the mold. This study explored the possibility of using the compression transfer molding process and also identified the key parameters regarding the process.

APA, Harvard, Vancouver, ISO, and other styles

14

Bechtold, G., M. Sakaguchi, K. Friedrich, and H. Hamada. "Pultrusion of Micro-Braided GF/PA6 Yarn." Advanced Composites Letters 8, no. 6 (November 1999): 096369359900800. http://dx.doi.org/10.1177/096369359900800605.

Full text

Abstract:

The present paper reports about experimental investigations on a new type of thermoplastic intermediate material (TP-prepreg). Today, most processes for producing fibre reinforced composite parts with thermoplastic matrices require expensive prepregs like pre-impregnated tapes or hybrid yarns (commingled yarns or powder impregnated yarns). The microbraiding technique offers some advantages compared to existing prepregs: Microbraided yarns can be produced directly by the user by a microbraiding process requiring only glass rovings and polymer rovings, and at the same time, the user is free of any restrictions on fibre/matrix combinations or reinforcement fibre content. Glass Fibre/Polyamide 6 (Nylon 6) microbraided yarn was compared to commercially available GF/PA6 tape concerning the use in a pultrusion process. For mechanical characterisation, shear strength and bending strength were determined. The processing parameters such as preheating temperature, heated die temperature and pulling speed were varied.

APA, Harvard, Vancouver, ISO, and other styles

15

Akinci, Akin, Ahmet Güleç, and Fevzi Yilmaz. "The Applicability of GRP and NRP Composites in Rehabilitation of Unpressurized Pipes." Advanced Materials Research 83-86 (December 2009): 563–70. http://dx.doi.org/10.4028/www.scientific.net/amr.83-86.563.

Full text

Abstract:

Glass fiber reinforced polymer (GRP) and needle reinforced polymer (NRP) composites have been used to produce a new kind of thin cross section liner for rehabilitation of in ground sewer pipes. The liner made from resin impregnated glass fiber woven (or plastic needle felt) is in-placed and cured for the rehabilitation of deteriorated pipe. This technique is entitled as cured in place pipe (CIPP) and penetrating to all over the world. Among the renovation technologies, CIPP appears less expensive and more promising than other techniques. CIPP liners are made up of several reinforcement layers impregnated with various thermosetting resins such as epoxy, vinyl ester and unsaturated polyester. Different woven geometries can be used for the felt and tube. In this study, the experimental results obtained from cured composites are given. The mechanical characteristics of CIPP tubes manufactured with different materials were given. Specifically glass fiber and synthetic felt impregnated in thermosetting unsaturated polyester resin were investigated. Standard three point flexural tests were carried out on specimens cut out from the cured liners. Beside these three point flexural tests, abrasive and erosive wear tests were also performed on these samples.

APA, Harvard, Vancouver, ISO, and other styles

16

Micelli, Francesco, and Maria Antonietta Aiello. "Residual tensile strength of dry and impregnated reinforcement fibres after exposure to alkaline environments." Composites Part B: Engineering 159 (February 2019): 490–501. http://dx.doi.org/10.1016/j.compositesb.2017.03.005.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Schneider, Kai, Albert Michel, Marco Liebscher, Lucas Terreri, Simone Hempel, and Viktor Mechtcherine. "Mineral-impregnated carbon fibre reinforcement for high temperature resistance of thin-walled concrete structures." Cement and Concrete Composites 97 (March 2019): 68–77. http://dx.doi.org/10.1016/j.cemconcomp.2018.12.006.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Wolter, Nick, Vinicius Carrillo Beber, Anna Sandinge, Per Blomqvist, Frederik Goethals, Marc Van Hove, Elena Jubete, Bernd Mayer, and Katharina Koschek. "Carbon, Glass and Basalt Fiber Reinforced Polybenzoxazine: The Effects of Fiber Reinforcement on Mechanical, Fire, Smoke and Toxicity Properties." Polymers 12, no. 10 (October 15, 2020): 2379. http://dx.doi.org/10.3390/polym12102379.

Full text

Abstract:

Bisphenol F and aniline-based benzoxazine monomers were selected to fabricate basalt, glass and carbon fiber reinforced polybenzoxazine via vacuum infusion, respectively. The impacts of the type of fiber reinforcement on the resulting material properties of the fiber reinforced polymers (FRPs) were studied. FRPs exhibited a homogenous morphology with completely impregnated fibers and near-zero porosity. Carbon fiber reinforced polybenzoxazine showed the highest specific mechanical properties because of its low density and high modulus and strength. However, regarding the flammability, fire, smoke and toxicity properties, glass and basalt reinforced polybenzoxazine outperformed carbon fiber reinforced polybenzoxazine. This work offers a deeper understanding of how different types of fiber reinforcement affect polybenzoxazine-based FRPs and provides access to FRPs with inherently good fire, smoke and toxicity performance without the need for further flame retardant additives.

APA, Harvard, Vancouver, ISO, and other styles

19

Park, Jongho, Sungnam Hong, and Sun-Kyu Park. "Experimental Study on Flexural Behavior of TRM-Strengthened RC Beam: Various Types of Textile-Reinforced Mortar with Non-Impregnated Textile." Applied Sciences 9, no. 10 (May 15, 2019): 1981. http://dx.doi.org/10.3390/app9101981.

Full text

Abstract:

In this study, to compare strengthening efficiency and flexural behaviors of textile- reinforced mortar (TRM) according to various types of strengthening methods without the textile being impregnated, ten specimens were tested. The results showed that TRM was beneficial for uniform distribution of cracks and increased the strengthening efficiency and load-bearing capacity, as textile reinforcement ratio and textile lamination increased and the mesh size of the textile decreased and mechanical end anchorage applied. However, the strengthening effect was shown obviously until the yield load considering structural safety and serviceability.

APA, Harvard, Vancouver, ISO, and other styles

20

Mechtcherine, Viktor, Albert Michel, Marco Liebscher, Kai Schneider, and Christoph Großmann. "Mineral-impregnated carbon fiber composites as novel reinforcement for concrete construction: Material and automation perspectives." Automation in Construction 110 (February 2020): 103002. http://dx.doi.org/10.1016/j.autcon.2019.103002.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Rogov, Vitaly Evdokimovich, and Anna S. Chermoshentseva. "Perspective Composite Material Made of Volume Fabric - Experimental Tests." Materials Science Forum 1022 (February 2021): 152–58. http://dx.doi.org/10.4028/www.scientific.net/msf.1022.152.

Full text

Abstract:

In all industries, composite materials with a multilayer structure are widely used. Each layer of the composite material is a directional fiber impregnated with a binder polymer. Layered composite materials, possessing unique properties and high manufacturability, have a significant drawback - the presence of interlayer defects in material, which reduces the scope of their application. One of the perspective directions for reducing the process of interlayer fracture in composite materials is the use of bulk textile material, which is the reinforcement of the entire multilayer material. This article presents an overview of some researches that provide basic information about the creation of perspective composite material made of volume fabric and materials based on them. We provided open information about manufacturers of 3D fabric materials. We carried out experimental tests with composite materials, which showed that material with transverse threads is 30-35% stronger during end impact than a composite material without reinforcement.

APA, Harvard, Vancouver, ISO, and other styles

22

Mechtcherine, Viktor, Albert Michel, Marco Liebscher, and Tobias Schmeier. "Extrusion-Based Additive Manufacturing with Carbon Reinforced Concrete: Concept and Feasibility Study." Materials 13, no. 11 (June 4, 2020): 2568. http://dx.doi.org/10.3390/ma13112568.

Full text

Abstract:

Additive manufacturing with cement-based materials needs sound approaches for the direct, seamless integration of reinforcement into structural and non-structural elements during their fabrication. Mineral-impregnated Carbon-Fibre (MCF) composites represent a new type of non-corrosive reinforcement that offers great potential in this regard. MCF not only exhibits high performance with respect to its mechanical characteristics and durability, but it also can be processed and shaped easily in the fresh state and, what is more, automated. This article describes different concepts for the continuous, fully automated integration of MCF reinforcement into 3D concrete printing based on layered extrusion. Moreover, for one of the approaches presented and discussed, namely 3D concrete printing with MCF supply from a continuous, stationary impregnation line and deposition of MCF between concrete filaments, a feasibility study was performed using a gantry 3D printer. Small-scale walls were printed and eventually used for the production of specimens for mechanical testing. Three-point bend tests performed on two different beam geometries showed a significant enhancement of both flexural strength and, more especially, deformability of the specimens reinforced with MCF in comparison to the specimens made of plain concrete.

APA, Harvard, Vancouver, ISO, and other styles

23

Petersen, R. C. "Discontinuous Fiber-reinforced Composites above Critical Length." Journal of Dental Research 84, no. 4 (April 2005): 365–70. http://dx.doi.org/10.1177/154405910508400414.

Full text

Abstract:

Micromechanical physics of critical fiber length, describing a minimum filament distance for resin impregnation and stress transfer, has not yet been applied in dental science. As a test of the hypothesis that 9-micron-diameter, 3-mm-long quartz fibers would increase mechanical strength over particulate-filled composites, photocure-resin-pre-impregnated discontinuous reinforcement was incorporated at 35 wt% into 3M Corporation Z100, Kerr Corporation HerculiteXRV, and an experimental photocure paste with increased radiopaque particulate. Fully articulated four-point bend testing per ASTM C 1161-94 for advanced ceramics and Izod impact testing according to a modified unnotched ASTM D 256-00 specification were then performed. All photocure-fiber-reinforced composites demonstrated significant improvements over particulate-filled compounds (p < 0.001) for flexural strength, modulus, work of fracture, strain at maximum load, and Izod toughness, with one exception for the moduli of Z100 and the experimental reinforced paste. The results indicate that inclusion of pre-impregnated fibers above the critical aspect ratio yields major advancements regarding the mechanical properties tested.

APA, Harvard, Vancouver, ISO, and other styles

24

Neves, Rui, and Diogo Felicíssimo. "Control of Cracking in Textile Reinforced Concrete with Unresin Carbon Fibers." Materials 13, no. 14 (July 18, 2020): 3209. http://dx.doi.org/10.3390/ma13143209.

Full text

Abstract:

Textile reinforced concrete (TRC) is an emerging construction material with interesting potential concerning sustainability, providing corrosion-free and lightweight solutions. Ordinarily, fiber bundles, impregnated with resin, are used. In this research the performance of reinforcement with unresin fibers is investigated. Control of cracking is considered the key performance factor and is assessed through tensile testing. However, economic and environmental aspects are addressed as well. Then, four different mixes/matrices were considered, without the addition of special/expensive admixtures. TRC ties were subject to direct tension tests, with load and deformation monitoring to assess the influence of mechanical reinforcement ratio on the cracking, failure and toughness of these composites, as well as of the matrix properties on the maximum load. It was observed that at a macro-level TRC behaves like conventional reinforced concrete, concerning crack control. Based on the maximum loads attained at the different composites, it was found that this particular TRC is economically viable. It is suggested that matrix workability may influence the maximum load.

APA, Harvard, Vancouver, ISO, and other styles

25

Vlach, Tomáš, Lenka Laiblová, Michal Ženíšek, Jakub Řepka, and Petr Hájek. "Soft Insert for Support Modeling of Slightly Textile Reinforced Concrete." Key Engineering Materials 760 (January 2018): 158–63. http://dx.doi.org/10.4028/www.scientific.net/kem.760.158.

Full text

Abstract:

This paper presents a model of small experimental facade panel using four-point bending test. The facade panel with dimensions 100 x 360 mm and thickness approximately 18 mm was slightly reinforced using two layers of impregnated technical fabric from AR-glass roving. The amount of reinforcement in cross-sectional area of the concrete element is small and it is a reason of plastic joints initiation under the loading supports. The purpose of this experiment was validation of all used material parameters from the previous research in the program for nonlinear analysis of concrete and reinforced concrete Atena Engineering. For slightly reinforced concrete elements are monitored parameters better visible especially interaction between reinforcement and used concrete. The load transfer to the concrete element from the testing machine is typically modeled using some small steel plate. This paper shows the difference in results if we insert another flexible plate between the steel plate and the concrete element with a small defined stiffness.

APA, Harvard, Vancouver, ISO, and other styles

26

Bobrikov, L. P., V. A. Galich, and A. V. Sandalov. "Diagnosing the binder content in impregnated reinforcement material by using the results of contactless ultrasound inspection." Mechanics of Composite Materials 21, no. 5 (1986): 639–44. http://dx.doi.org/10.1007/bf00610575.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Endruweit, Andreas, Paul Glover, Kay Head, and Andrew C. Long. "Mapping of the fluid distribution in impregnated reinforcement textiles using Magnetic Resonance Imaging: Methods and issues." Composites Part A: Applied Science and Manufacturing 42, no. 3 (March 2011): 265–73. http://dx.doi.org/10.1016/j.compositesa.2010.11.012.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Endruweit, Andreas, Paul Glover, Kay Head, and Andrew C. Long. "Mapping of the fluid distribution in impregnated reinforcement textiles using Magnetic Resonance Imaging: Application and discussion." Composites Part A: Applied Science and Manufacturing 42, no. 10 (October 2011): 1369–79. http://dx.doi.org/10.1016/j.compositesa.2011.05.020.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Rempel, Sergej, and Christian Kulas. "Biegetragverhalten getränkter textiler Bewehrungselemente für Betonbauteile/Bending Bearing Behavior of impregnated textile reinforcement for concrete elements." Bauingenieur 90, no. 06 (2015): 248–51. http://dx.doi.org/10.37544/0005-6650-2015-06-40.

Full text

Abstract:

Der Trend in der heutigen Bauwirtschaft zeigt einen wachsenden Bedarf an hochleistungsfähigen Materialien mit hohen Zug- und Druckfestigkeiten. Ein innovatives Baumaterial, das die Wünsche der Architekten und Tragwerksplaner befriedigt, ist der Textilbeton (Textile-Reinforced-Concrete (TRC)). Die Kombination aus hochfestem Beton und der korrosionsbeständigen Bewehrung, die gleichzeitig mit einer hohen Zugfestigkeit überzeugt, ermöglicht extrem schlanke Bauteile. Die bereits realisierten Textilbeton-Anwendungen bekräftigen die Anwendbarkeit des neuen Verbundwerkstoffes. Die weitere Entwicklung der textilen Bewehrung erweitert die Möglichkeiten für tragende Bauteile. Ein wichtiger Schritt war die Imprägnierung der Textilien mit Styrol-Butadien und Epoxidharz. Die Tränkung ermöglicht einen hohen Zuwachs der Zugfestigkeiten. Zusätzlich wird die Dauerhaftigkeit, Handhabung und Temperaturstabilität der Bewehrung erhöht. Folglich steigen die Effektivität und die Wirtschaftlichkeit der texilbewehrten Bauteile.   Der Beitrag stellt das Biegetragverhalten von Platten sowie Doppel-T Balken vor, die mit getränkten Textilien bewehrt wurden. Des Weiteren wird ein Bemessungsmodell für das Biegetragverhalten vorgestellt.

APA, Harvard, Vancouver, ISO, and other styles

30

Goergen, C., D. May, and P. Mitschang. "Integration of rCF in resin transfer pressing process." Journal of Reinforced Plastics and Composites 39, no. 9-10 (February 23, 2020): 361–72. http://dx.doi.org/10.1177/0731684420906879.

Full text

Abstract:

A new composite manufacturing process, resin transfer pressing, is introduced in this paper. In this process, nonwoven fabrics made of recycled carbon fibers are oversaturated with thermoset resin, i.e. they contain excess resin. The oversaturated nonwoven fabrics are prefabricated and used as resin carrier in a press process, where they are placed in a heated mold together with a dry textile-based preform. During pressing, the resin is pressed out and transferred from the nonwoven into the non-impregnated preform and hence impregnates the whole reinforcement. This study examines the oversaturation of nonwoven fabrics, the resin transfer pressing laminate manufacturing and the surface quality of the laminates. The ability of a nonwoven fabric to be oversaturated with resin is defined by the saturation degree, which was determined as up to 12 for glass fiber nonwoven fabrics and up to 60 for recycled carbon fiber nonwoven fabrics. Different laminates are manufactured by resin transfer pressing, and the impregnation quality is evaluated. With an optimized stacking sequence, a pore content <1% was achieved. The use of recycled carbon fiber nonwovens in the resin transfer pressing process leads to a less wavy surface compared to a wet compression molding manufactured laminate, showing a decrease of waviness Wz25 of 11% minimum.

APA, Harvard, Vancouver, ISO, and other styles

31

Morales Cruz, Cynthia, and Michael Raupach. "Influence of the surface modification by sanding of carbon textile reinforcements on the bond and load-bearing behavior of textile reinforced concrete." MATEC Web of Conferences 289 (2019): 04006. http://dx.doi.org/10.1051/matecconf/201928904006.

Full text

Abstract:

In the context of the application of carbon Textile Reinforced Concrete (TRC) layers for the durable repair of building surfaces, uniaxial tensile tests on rectangular TRC samples were carried out to compare the bond and load-bearing behavior of an epoxy-impregnated carbon textile and its surface modified version. The aim of the surface modification, consisting of a subsequent coating with epoxy resin and sanding with quartz sand, is the improvement of the composite material regarding crack width reduction and an increase of the load-bearing capacity. A total of 15 series were examined and the parameters: reinforcement type, orientation and ratio were varied. In addition, long-term load tests were conducted. An optical 3D-video measuring system in combination with a DIC-software was used, which allowed the analysis of the process of crack formation during the entire testing time. With the surface modified reinforcement the formation of approx. 1.5 times the number of cracks with averagely 33 % smaller crack widths and up to 50 % smaller crack spacings were observed, regardless of the ratio of reinforcement. The residual behaviour of the series subjected to a permanent load of 1500 MPa over 1000 h showed no reduction of the tensile stress compared to short-term tests.

APA, Harvard, Vancouver, ISO, and other styles

32

Lecointe, Damien, Maxime Villière, Sawsane Nakouzi, Vincent Sobotka, Nicolas Boyard, Fabrice Schmidt, and D. Delaunay. "Experimental Determination and Modeling of Thermal Conductivity Tensor of Carbon/Epoxy Composite." Key Engineering Materials 504-506 (February 2012): 1091–96. http://dx.doi.org/10.4028/www.scientific.net/kem.504-506.1091.

Full text

Abstract:

In this study, the effective thermal conductivity tensor of carbon/epoxy laminates was investigated experimentally in the three states of a typical LCM-process: dry-reinforcement, raw and cured composite. Samples were made of twill-weave carbon fabric impregnated with epoxy resin. The transverse thermal conductivity was determined using a classical estimation algorithm, whereas a special testing apparatus was designed to estimate in-plane conductivity for different temperatures and different states of the composite. Experimental results were then compared to modified Charles & Wilson and Maxwell models. The comparison showed clearly that these models can be used to accurately and efficiently predict the effective thermal conductivities of woven-reinforced composites.

APA, Harvard, Vancouver, ISO, and other styles

33

Inyang, Adijat Omowumi, and Christopher Leonard Vaughan. "Functional Characteristics and Mechanical Performance of PCU Composites for Knee Meniscus Replacement." Materials 13, no. 8 (April 17, 2020): 1886. http://dx.doi.org/10.3390/ma13081886.

Full text

Abstract:

The potential use of fiber-reinforced based polycarbonate-urethanes (PCUs) as candidate meniscal substitutes was investigated in this study. Mechanical test pieces were designed and fabricated using a compression molding technique. Ultra-High Molecular Weight Polyethylene (UHMWPE) fibers were impregnated into PCU matrices, and their mechanical and microstructural properties evaluated. In particular, the tensile moduli of the PCUs were found unsuitable, since they were comparatively lower than that of the meniscus, and may not be able to replicate the inherent role of the meniscus effectively. However, the inclusion of fibers produced a substantial increment in the tensile modulus, to a value within a close range measured for meniscus tissues. Increments of up to 227% were calculated with a PCU fiber reinforcement composite. The embedded fibers in the PCU composites enhanced the fracture mechanisms by preventing the brittle failure and plastic deformation exhibited in fractured PCUs. The behavior of the composites in compression varied with respect to the PCU matrix materials. The mechanical characteristics demonstrated by the developed PCU composites suggest that fiber reinforcements have a considerable potential to duplicate the distinct and multifaceted biomechanical roles of the meniscus.

APA, Harvard, Vancouver, ISO, and other styles

34

Karthikeyan, S. "Influence of fibre loading and surface treatment on the impact strength of coir polyester composites." Archives of Materials Science and Engineering 1, no. 107 (January 3, 2021): 16–20. http://dx.doi.org/10.5604/01.3001.0014.8190.

Full text

Abstract:

Purpose: In this work, coir fibre with varying fibre content was selected as reinforcements to prepare polymer-based matrices and the problem of reduced fibre-matrix interfacial bond strength has been diluted by chemical treatment of coir fibres with alkali solution. Design/methodology/approach: The effect of fibre loading, solution concentration and soaking time on the impact strength of the composites were analyzed using statistical techniques. Response Surface Methodology (RSM) approach was used to model and optimize the impact properties of coir-polyester composites. Findings: The impact strength of coir fibre reinforced polyester composite depends mainly on the fabrication parameters such as fibre-polyester content, soaking time, concentration of soaking agent and adhesive interaction between the fibre and reinforcement. Research limitations/implications: The mechanical properties of any coir polyester composite depend on the nature bonding between the fibre and reinforcement. The presence of cellulose, lignin on the periphery of any natural fibre reduces the bonding strength of the composite. This limitation is overcome by fibre treatment over sodium hydroxide to have better impact properties. Practical implications: Now days, natural fibre reinforced composites are capable of replacing automotive parts, subjected to static loads such as engine Guard, light doom, name plate, tool box and front panels etc. These materials can withstand any static load due to its higher strength to weight ratios. Originality/value: The effect of fibre loading, solution concentration and soaking time on the impact strength of the composites were analyzed using statistical techniques. Response Surface Methodology (RSM) approach was used to model and optimize the impact properties of coir-polyester composites. The impact strength of NaOH impregnated coir fibre reinforced polyester composites was evaluated.

APA, Harvard, Vancouver, ISO, and other styles

35

Dvorkin, D., and A. Peled. "Effect of reinforcement with carbon fabrics impregnated with nanoparticles on the tensile behavior of cement-based composites." Cement and Concrete Research 85 (July 2016): 28–38. http://dx.doi.org/10.1016/j.cemconres.2016.03.008.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

Lin, Jia Horng, Ting Ting Li, Mei Chen Lin, Jan Yi Lin, and Ching Wen Lou. "Preliminary Study of Puncture-Resisting Needle-Punched 3D Composites with Varying Reinforcements." Applied Mechanics and Materials 749 (April 2015): 274–77. http://dx.doi.org/10.4028/www.scientific.net/amm.749.274.

Full text

Abstract:

Logistics industry becomes the mainstream with promotion of life quality. The selection of delivery type and aging is subjected to limitations of packaging materials. In order to protect from product’s damage, this study purposes to use recycled high-strength fibers, including high-strength PET fiber, and Kevlar fibers, and thermal bonding PET fiber as well as glass fabric forming needle-punched 3D composite. For comparison of varying reinforcement on mechanical property, thermal bonding and water polyurethane impregnation are used to reinforce the 3D composite which is composed of nonwoven fabrics and glass fabrics. Result shows that, mechanical property from water polyurethane impregnation displayed much higher than that from thermal bonding. Thermal bonding remarkably improved burst strength and static puncture resistance. Therefore, 3D composite impregnated with water polyurethane reaches higher puncture protection level.

APA, Harvard, Vancouver, ISO, and other styles

37

Reis Silva, Miguel, António M. Pereira, Nuno Alves, Gonçalo Mateus, Artur Mateus, and Cândida Malça. "Development of an Additive Manufacturing System for the Deposition of Thermoplastics Impregnated with Carbon Fibers." Journal of Manufacturing and Materials Processing 3, no. 2 (April 27, 2019): 35. http://dx.doi.org/10.3390/jmmp3020035.

Full text

Abstract:

This work presents an innovative system that allows the oriented deposition of continuous fibers or long fibers, pre-impregnated or not, in a thermoplastic matrix. This system is used in an integrated way with the filamentary fusion additive manufacturing technology and allows a localized and oriented reinforcement of polymer components for advanced engineering applications at a low cost. To demonstrate the capabilities of the developed system, composite components of thermoplastic matrix (polyamide) reinforced with pre-impregnated long carbon fiber (carbon + polyamide), 1 K and 3 K, were processed and their tensile and flexural strength evaluated. It was demonstrated that the tensile strength value depends on the density of carbon fibers present in the composite, and that with the passage of 2 to 4 layers of fibers, an increase in breaking strength was obtained of about 366% and 325% for the 3 K and 1 K yarns, respectively. The increase of the fiber yarn diameter leads to higher values of tensile strength of the composite. The obtained standard deviation reveals that the deposition process gives rise to components with anisotropic mechanical properties and the need to optimize the processing parameters, especially those that lead to an increase in adhesion between deposited layers.

APA, Harvard, Vancouver, ISO, and other styles

38

Obradović, Vera, Dušica B. Stojanović, Radmila Jančić - Heinemann, Irena Živković, Vesna Radojević, Petar S. Uskoković, and Radoslav Aleksić. "Ballistic Properties of Hybrid Thermoplastic Composites with Silica Nanoparticles." Journal of Engineered Fibers and Fabrics 9, no. 4 (December 2014): 155892501400900. http://dx.doi.org/10.1177/155892501400900412.

Full text

Abstract:

Multi-axial aramid fabrics have a wide range of applications in the construction of composite structures for body armor. Nanoparticles, which include nanosilica, are one of the most common nanofillers for these structures. The particles of nanosilica possess nanometer dimensions with high specific surface area. Silane coupling agents are mostly used for modifying nanosilica surface in order to prevent silica agglomeration. Incorporation of nanosilica treated with silane adhesion promoter, in the matrix part of the hybrid composite form, leads to increased resistance to the bullet shock impact. In this study, the resistance to penetration of a shot bullet was tested for four samples of the aramid fabric composite forms. All fabrics were coated with γ-aminopropyl triethoxysilane (AMEO silane)/ethanol solution. Two samples were impregnated with poly (vinyl butyral) (PVB)/ethanol solution, while the other two were impregnated with the same solution, but with the addition of the 30 wt.% AMEO silane modified silica nanoparticles as reinforcement. The samples were both hard and flexible options. The bullet-shooting test was applied to all the composites by two different bullet types. The structural design of the samples improved the ballistic resistance after the bullets were shot. Some ballistic image analyses for print and penetration depth of the samples were performed using Image Pro-Plus software.

APA, Harvard, Vancouver, ISO, and other styles

39

El Naggar, Shady M., Mohamed I. Seif El Nasr, Hassan M. Sakr, Sherihan M. Eissa, Asmaa N. Elboraey, and Amani R. Moussa. "Effect of Denture Base Reinforcement Using Light Cured E- Glass Fibers on the Level of Salivary Immunoglobulin A." Open Access Macedonian Journal of Medical Sciences 6, no. 11 (November 8, 2018): 2168–72. http://dx.doi.org/10.3889/oamjms.2018.419.

Full text

Abstract:

BACKGROUND: A gap still exists between in vitro and clinical studies concerning the biocompatibility of the material in the oral environment and their potential to cause immunological undesirable side effects. The uses of glass fibres to improve the mechanical properties of acrylic resin denture base polymers are well documented in vitro. AIM: The present study aimed to evaluate the effect of denture base reinforcement using light-cured E- glass fibres mesh on the level of salivary immunoglobulin A (S-IgA) in patients wearing complete dentures. MATERIAL AND METHODS: Fourteen completely edentulous patients, in need of complete dentures, participated in the study. The patients were divided into two groups (n = 7) according to the treatment protocol. In the first group, patients received conventional heat-cured acrylic resin dentures. In the second group, the mandibular dentures were reinforced using light cured resin impregnated E glass fibres mesh. In both groups, salivary samples were collected using passive drool technique. The level IgA was assessed by enzyme-linked immunosorbent assay (ELISA) technique at different time intervals. Statistical analysis was carried out using one-way ANOVA followed by Tukey`s post-hoc test and independent t-test. The significant level was set at P ≤ 0.05. RESULTS: Acrylic resin dentures and reinforced ones demonstrated an increase in the mean values of IgA level at the end of the follow-up intervals. And this increase was statistically significant (P ≤ 0.05). Although, the reinforced dentures revealed higher mean values, there was no statistically significant difference between the two groups (P > 0.05) CONCLUSIONS: Within the limitations of the present study, the following could be concluded: (1) the insertion of complete dentures induced changes in the level of IgA; and (2) denture base reinforcement using light cured resin impregnated E-glass fibres mesh had a similar effect to that of heat cured acrylic resin on the level of IgA.

APA, Harvard, Vancouver, ISO, and other styles

40

Gheorghe, Vasile, Florin Teodorescu-Draghicescu, and Dora Raluca Ionescu. "Failure of an Advanced Five Layers RT800 Composite." Applied Mechanics and Materials 760 (May 2015): 299–304. http://dx.doi.org/10.4028/www.scientific.net/amm.760.299.

Full text

Abstract:

This paper presents mechanical properties of five layers RT800 glass mat laminate impregnated with polyester resin and subjected to three-point bending tests until break. The RT800 glass mat used as reinforcement presents randomly disposed short glass fibers with 845 g/m2specific weight. From the cured plate, twenty specimens have been cut and placed on a three-point bending device and tested using a materials testing machine with servo hydraulic command. The specimens have been carried out at Compozite Ltd Brasov and the experimental tests have been accomplished at SC INAR SA Brasov and Transilvania University of Brasov. Outstanding mechanical properties of this kind of material have been found in which the specimens have suffered delamination mainly in their median part.

APA, Harvard, Vancouver, ISO, and other styles

41

Liu, Liang Sen, Ye Xiong Qi, and Jia Lu Li. "Bending Properties of Four-Layer Biaxial Weft Knitted Fabric Reinforced Composite Materials." Applied Mechanics and Materials 182-183 (June 2012): 89–92. http://dx.doi.org/10.4028/www.scientific.net/amm.182-183.89.

Full text

Abstract:

In this paper, a kind of composite laminates whose reinforcement is four-layer biaxial weft knitted (FBWK)fabric made of carbon fiber as inserted yarns has been made. The composite laminates have been impregnated with epoxy resin via resin transfer molding (RTM) technique. The samples of the experiments have been made from the composite laminates. The bending properties of the FBWK fabric reinforced composite materials with different fiber volume fraction have been investigated. The results show that the bending strength of this kind of composites increases with the fiber volume fraction increasing. The bending strength of FBWK reinforced composites with fiber volume fraction of 52% can reach 695.86 MPa. And the relationship between bending load and deflection is obviously linear.

APA, Harvard, Vancouver, ISO, and other styles

42

Chtourou, Halim, Jean-Philippe Massie-Martel, Norayr Gurnagul, and Michelle Ricard. "Paper twines in the pultrusion process – Pilot production and flexural characterization of sandwich rods." Journal of Composite Materials 53, no. 21 (November 12, 2018): 3005–19. http://dx.doi.org/10.1177/0021998318811520.

Full text

Abstract:

This paper describes the possibility of the use of paper twines as core reinforcement in thermoset pultruded sandwich composites. Paper twines and glass fiber rovings were co-impregnated with polyester resin and co-pultruded to form sandwich rods. Pultruded sandwich rods were up to 26% lighter with regard to typical monolithic glass fiber reinforced polyester rods. The specific flexural strength and Young's modulus of the sandwich rods were up to 25% higher than those of monolithic glass fiber/polyester commercial rods. Thanks to its light weight and its availability as a continuous twine, paper twines may be used with great flexibility in pultrusion of sandwich structures. This may lead to up to 20–30% weight reduction and cost saving without losing flexural performance.

APA, Harvard, Vancouver, ISO, and other styles

43

Zhang, Peng, Huaishuai Shang, Dongshuai Hou, Siyao Guo, and Tiejun Zhao. "The Effect of Water Repellent Surface Impregnation on Durability of Cement-Based Materials." Advances in Materials Science and Engineering 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/8260103.

Full text

Abstract:

In many cases, service life of reinforced concrete structures is severely limited by chloride penetration until the steel reinforcement or by carbonation of the covercrete. Water repellent treatment on the surfaces of cement-based materials has often been considered to protect concrete from these deteriorations. In this paper, three types of water repellent agents have been applied on the surface of concrete specimens. Penetration profiles of silicon resin in treated concrete have been determined by FT-IR spectroscopy. Water capillary suction, chloride penetration, carbonation, and reinforcement corrosion in both surface impregnated and untreated specimens have been measured. Results indicate that surface impregnation reduced the coefficient of capillary suction of concrete substantially. An efficient chloride barrier can be established by deep impregnation. Water repellent surface impregnation by silanes also can make the process of carbonation action slow. In addition, it also has been concluded that surface impregnation can provide effective corrosion protection to reinforcing steel in concrete with migrating chloride. The improvement of durability and extension of service life for reinforced concrete structures, therefore, can be expected through the applications of appropriate water repellent surface impregnation.

APA, Harvard, Vancouver, ISO, and other styles

44

KANIE, Takahito, Hiroyuki ARIKAWA, Koichi FUJII, and Seiji BAN. "Light-curing Reinforcement for Denture Base Resin Using a Glass Fiber Cloth Pre-impregnated with Various Urethane Oligomers." Dental Materials Journal 23, no. 3 (2004): 291–96. http://dx.doi.org/10.4012/dmj.23.291.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Margossian, Alexane, François Dumont, and Uwe Beier. "Validation of Macroscopic Forming Simulations of a Unidirectional Pre-Impregnated Material through Optical Measurements." Key Engineering Materials 554-557 (June 2013): 465–71. http://dx.doi.org/10.4028/www.scientific.net/kem.554-557.465.

Full text

Abstract:

Presenting interesting aspects such as a high strength-to-weight ratio, Carbon Fibre Reinforced Plastic components are frequently used in the aerospace industry. The forming step, which conforms the reinforcement to a specific geometry, is a sensitive phase of the manufacturing process. In order to detect the occurrence of defects prior to any trial, forming methods are often simulated via finite element software. The presented work will detail the simulation validation of a double curved helicopter frame forming out of a unidirectional carbon fibre pre-impregnated material (M21E, Hexcel®). The finite element model was based on an explicit approach at a macroscopic level and developed via the commercially available software Visual-Crash PAM (ESI®) [1]. The validation was carried out on six different preforms. Measurements of the top layers were performed by an enhanced version of a 4D measuring system, originally developed for non-woven fabric [2], able to make reproducible photographic and height measurements (Fig. 1). Experimental results were then compared to simulated ones. Due to material specificities, the photo quality reached for non-crimp fabrics could not be achieved [2]. After hardware and software modifications, measurements and analyses were eventually successfully completed. The validation of the simulation reached an accuracy of 1° to 3° depending on the geometrical features of the preform (Fig. 2).

APA, Harvard, Vancouver, ISO, and other styles

46

Hobzova, Radka, Jakub Hrib, Jakub Sirc, Evgeny Karpushkin, Jiri Michalek, Olga Janouskova, and Paul Gatenholm. "Embedding of Bacterial Cellulose Nanofibers within PHEMA Hydrogel Matrices: Tunable Stiffness Composites with Potential for Biomedical Applications." Journal of Nanomaterials 2018 (2018): 1–11. http://dx.doi.org/10.1155/2018/5217095.

Full text

Abstract:

Bacterial cellulose (BC) and poly(2-hydroxyethyl methacrylate) (PHEMA) hydrogels are both considered as biocompatible materials with potential use in various biomedical applications including cartilage, cardiovascular stent, and soft tissue engineering. In this work, the “ever-wet” process based on in situ UV radical polymerization of HEMA monomer in BC nanofibrous structure impregnated with HEMA was used, and a series of BC-PHEMA composites was prepared. The composite structures were characterized by ATR FT-IR spectroscopy, WAXD, SEM, and TEM techniques. The strategy of using densified BC material of various cellulose fiber contents was applied to improve mechanical properties. The mechanical properties were tested under tensile, dynamic shear, and relaxation modes. The final composites contained 1 to 20 wt% of BC; the effect of the reinforcement degree on morphology, swelling capacity, and mechanical properties was investigated. The biocompatibility test of BC-PHEMA composites was performed using mouse mesenchymal stem cells.

APA, Harvard, Vancouver, ISO, and other styles

47

Goutianos, S., and T. Peijs. "The Optimisation of Flax Fibre Yarns for the Development of High-Performance Natural Fibre Composites." Advanced Composites Letters 12, no. 6 (November 2003): 096369350301200. http://dx.doi.org/10.1177/096369350301200602.

Full text

Abstract:

Currently most developments in the area of natural fibre reinforced composites have focused on random discontinuous fibre composite systems. The development of continuous fibre reinforced composites is, however, essential for manufacturing materials, which can be used in load-bearing/structural applications. The main problem in this case is the optimisation of the yarn to be used to manufacture the textile reinforcement. Low twisted yarns display a very low strength when tested dry in air and therefore they can not be used in processes such as pultrusion or textile manufacturing routes. On the other hand, by increasing the level of twist, a degradation of the mechanical properties is observed in impregnated yarns (e.g. unidirectional composites) similar to off-axis composites. Additionally, a high level of twist decreases the permeability of the yarns. This problem is addressed in the current work using yarns based on both long and short flax fibres.

APA, Harvard, Vancouver, ISO, and other styles

48

Morii, Tohru, Jan Ivens, and Ignaas Verpoest. "Interfacial Effects on the Mechanical Properties of Glass/Phenolic Composites." Advanced Composites Letters 8, no. 6 (November 1999): 096369359900800. http://dx.doi.org/10.1177/096369359900800604.

Full text

Abstract:

The effect of interface on the mechanical properties of glass fibre/phenolic composites is discussed in this paper. Standard and silane modified resins are used as matrix, and a yarn and two kinds of rovings with different sizing are used as reinforcement. The effect of fibre on wetting is evaluated, and it is shown that sizing specially developed for phenolic resin is quite effective to improve resin impregnation into the fibre bundle. The mechanical properties are evaluated by using the resin impregnated unidirectional fibre bundle composite specimens. The effects of resin and fibre on strength and crack propagation are evaluated by the lateral compression test. The type of the fibre affected the dispersion of fibres in the matrix resin, and the roving developed for phenolic resin gave the best dispersion of the fibre. This led the high mechanical properties and high resistance to the crack initiation.

APA, Harvard, Vancouver, ISO, and other styles

49

Li, Ting-Ting, Xixi Cen, Haokai Peng, Haitao Ren, Lianhe Han, Ching-Wen Lou, and Jia-Horng Lin. "Rheological response and quasi-static stab resistance of STF/MWCNTs-impregnated aramid fabrics with different textures." Journal of Industrial Textiles 50, no. 3 (February 18, 2019): 380–97. http://dx.doi.org/10.1177/1528083719830144.

Full text

Abstract:

Terrorist attacks occur constantly, which subsequently arouses awareness of self-protection. In order to alleviate the harm caused by sharp objects of knives and daggers, a design of flexible stab-resistant materials that are impregnated with the shear thickening fluid (STF)/multi-walled carbon nanotubes (MWCNTs) system and different texture of fabrics is presented. STF/MWCNTs are composed of polyethylene glycol (PEG 200) as the dispersion medium and silica (SiO2) of 12 nm and 75 nm as disperse phase as well as MWCNTs as supplementary reinforcement, in expectation to provide the aramid fabrics with high strengths, low critical shear rate, and a short thickening response time. The textures of aramid fabrics—plain (P), twill (T), satin (S), or basket (B) weave—are saturated in the STF/MWCNTs system. The synergetic influences of silica size and texture on tensile strength, quasi-static knife, and spike stab resistances of the STF/MWCNTs-impregnated aramid fabrics are examined. Results show that the plain aramid fabric immersed in the STF/MWCNTs system containing 12 nm SiO2(SM12) exhibit the maximum tensile strength and quasi-static knife stab resistance, 14.7 MPa and 8.9 MPa, respectively, which is 1.15 and 1.43 times higher than pure aramid fabrics. Moreover, the basket-weave aramid fabric immersed in the STF/MWCNTs system containing 12 nm SiO2have the maximum quasi-static spike stab resistance of 17.12 MPa compared to other textures of fabrics, which is 1.05 times higher than those immersed in the 75 nm SiO2STF/MWCNTs (SM75) system and 1.33 times higher than that of pure basket aramid fabrics.

APA, Harvard, Vancouver, ISO, and other styles

50

Moskvichev, Egor V., and Alexey Yu Larichkin. "Experimental study of the functional and mechanical properties of shape memory polymer composites for a reflector of the space antenna." Industrial laboratory. Diagnostics of materials 86, no. 1 (January 30, 2020): 51–56. http://dx.doi.org/10.26896/1028-6861-2020-86-1-51-56.

Full text

Abstract:

Experimental study of the shape memory polymer composite is carried out as a part of scientific and technological work aimed at development of the new promising reflectors for space antenna. The studied material consists of three-layered carbon biaxial fabric St 12073 impregnated with a polyurethane-based Diaplex MP5510 polymer matrix. This material is intended for manufacturing a frame used in the construction of a precise composite reflector of space antenna. When opening the reflector to the transport position, the rim activated by heating recovers a previously specified shape thus increasing the rigidity of the reflector at the periphery and enhancing the accuracy of the reflecting surface. To study the functional and mechanical properties of the rim material in manufacturing and operating conditions, experimental tests were carried out on the samples with different schemes of reinforcement: [03], [0/±60] and [0/±45]. The main goal of the study is to determine the degree and rate of the shape recovery, reinforcement angles, deformation rate and exposure time in the strained state. The developed test program included several stages. At the first stages, tests were carried out for fixing and restoring the shape upon three-point bending of flat samples at a strain rate of 1, 5, and 10 mm/sec and exposure of the specimens in deformed state for 24, 48, and 96 h. According to the results the material with the reinforcement angles [03] was accepted as optimal for the rim design, as it has maximal shape recovery parameters. For the selected material at the final stage of the study, the elastic modulus and tensile strength were determined at operating temperatures –50, +20, and +60°C. The tests showed that the studied polymer composite material has the desired shape memory properties and is promising for the rim manufacturing provided the heat insulation during operation.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Impregnated reinforcement'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles