Sample records for reinforced composite material

  1. Nanostructured composite reinforced material

    Seals, Roland D [Oak Ridge, TN; Ripley, Edward B [Knoxville, TN; Ludtka, Gerard M [Oak Ridge, TN


    A family of materials wherein nanostructures and/or nanotubes are incorporated into a multi-component material arrangement, such as a metallic or ceramic alloy or composite/aggregate, producing a new material or metallic/ceramic alloy. The new material has significantly increased strength, up to several thousands of times normal and perhaps substantially more, as well as significantly decreased weight. The new materials may be manufactured into a component where the nanostructure or nanostructure reinforcement is incorporated into the bulk and/or matrix material, or as a coating where the nanostructure or nanostructure reinforcement is incorporated into the coating or surface of a "normal" substrate material. The nanostructures are incorporated into the material structure either randomly or aligned, within grains, or along or across grain boundaries.

  2. Processes for fabricating composite reinforced material

    Seals, Roland D.; Ripley, Edward B.; Ludtka, Gerard M.


    A family of materials wherein nanostructures and/or nanotubes are incorporated into a multi-component material arrangement, such as a metallic or ceramic alloy or composite/aggregate, producing a new material or metallic/ceramic alloy. The new material has significantly increased strength, up to several thousands of times normal and perhaps substantially more, as well as significantly decreased weight. The new materials may be manufactured into a component where the nanostructure or nanostructure reinforcement is incorporated into the bulk and/or matrix material, or as a coating where the nanostructure or nanostructure reinforcement is incorporated into the coating or surface of a "normal" substrate material. The nanostructures are incorporated into the material structure either randomly or aligned, within grains, or along or across grain boundaries.

  3. Hybrid fiber reinforcement and crack formation in Cementitious Composite Materials

    Pereira, E.B.; Fischer, Gregor; Barros, J.A.O.


    reinforcement systems. The research described in this paper shows that the multi-scale conception of cracking and the use of hybrid fiber reinforcements do not necessarily result in an improved tensile behavior of the composite. Particular material design requirements may nevertheless justify the use of hybrid......- to the macroscale. In this study, the performance of different fiber reinforced cementitious composites is assessed in terms of their tensile stress-crack opening behavior. The results obtained from this investigation allow a direct quantitative comparison of the behavior obtained from the different fiber...

  4. Fiber-reinforced composites materials, manufacturing, and design

    Mallick, P K


    The newly expanded and revised edition of Fiber-Reinforced Composites: Materials, Manufacturing, and Design presents the most up-to-date resource available on state-of-the-art composite materials. This book is unique in that it not only offers a current analysis of mechanics and properties, but also examines the latest advances in test methods, applications, manufacturing processes, and design aspects involving composites. This third edition presents thorough coverage of newly developed materials including nanocomposites. It also adds more emphasis on underlying theories, practical methods, and problem-solving skills employed in real-world applications of composite materials. Each chapter contains new examples drawn from diverse applications and additional problems to reinforce the practical relevance of key concepts. New in The Third Edition: Contains new sections on material substitution, cost analysis, nano- and natural fibers, fiber architecture, and carbon-carbon composites Provides a new chapter on poly...

  5. Friction Stir Processing of Particle Reinforced Composite Materials

    Daniel Solomon


    Full Text Available The objective of this article is to provide a review of friction stir processing (FSP technology and its application for microstructure modification of particle reinforced composite materials. The main focus of FSP was on aluminum based alloys and composites. Recently, many researchers have investigated this technology for treating other alloys and materials including stainless steels, magnesium, titanium, and copper. It is shown that FSP technology is very effective in microstructure modification of reinforced metal matrix composite materials. FSP has also been used in the processing and structure modification of polymeric composite materials. Compared with other manufacturing processes, friction stir processing has the advantage of reducing distortion and defects in materials. The layout of this paper is as follows. The friction stir processing technology will be presented first. Then, the application of this technology in manufacturing and structure modification of particle reinforced composite materials will be introduced. Future application of friction stir processing in energy field, for example, for vanadium alloy and composites will be discussed. Finally, the challenges for improving friction stir processing technology will be mentioned.

  6. Hybrid fiber reinforcement and crack formation in Cementitious Composite Materials

    Pereira, E.B.; Fischer, Gregor; Barros, J.A.O.


    reinforcement systems. The research described in this paper shows that the multi-scale conception of cracking and the use of hybrid fiber reinforcements do not necessarily result in an improved tensile behavior of the composite. Particular material design requirements may nevertheless justify the use of hybrid......The use of different types of fibers simultaneously for reinforcing cementitious matrices is motivated by the concept of a multi-scale nature of the crack propagation process. Fibers with different geometrical and mechanical properties are used to bridge cracks of different sizes from the micro......- to the macroscale. In this study, the performance of different fiber reinforced cementitious composites is assessed in terms of their tensile stress-crack opening behavior. The results obtained from this investigation allow a direct quantitative comparison of the behavior obtained from the different fiber...



    A composite panel having front and back faces, the panel comprising facing reinforcement, backing reinforcement and matrix material binding to the facing and backing reinforcements, the facing and backing reinforcements each independently comprising one or more reinforcing sheets, the facing...... by matrix material, the facing and backing reinforcements being interconnected to resist out-of-plane relative movement. The reinforced composite panel is useful as a barrier element for shielding structures, equipment and personnel from blast and/or ballistic impact damage....



    A composite panel having front and back faces, the panel comprising facing reinforcement, backing reinforcement and matrix material binding to the facing and backing reinforcements, the facing and backing reinforcements each independently comprising one or more reinforcing sheets, the facing rein...... by matrix material, the facing and backing reinforcements being interconnected to resist out-of-plane relative movement. The reinforced composite panel is useful as a barrier element for shielding structures, equipment and personnel from blast and/or ballistic impact damage....

  9. Tensile & impact behaviour of natural fibre-reinforced composite materials

    Tobias, B.C. [Victoria Univ. of Technology, Footscray (Australia). Dept. of Mechanical Engineering


    Short abaca fiber reinforced composite materials are fabricated and investigated for short term performance. Abaca plants which grow in abundance in Asia contain fibers that are inexpensive but underutilized. This study attempts to utilize the abaca fibers for composite material structure as a possible alternative to timber products in building applications. The composite material is fabricated using the hand lay-up method under varying fiber length and fiber volume fraction. The fibers are impregnated with a mixture of resins which cures at room temperature. A fabricating facility is designed to accommodate fabrication of lamina. Tensile and impact properties are determined in relation to the length and volume fraction of the fiber. For a given fiber length, the tensile and impact strength increase as the volume fraction increases up to a limiting value. And for a given fiber volume fraction, the tensile strength increases but the impact strength decreases as the fiber length increases. This behavior of abaca fiber-reinforced composite lamina will help in optimizing the design parameter in random composite panels.

  10. Natural Kenaf Fiber Reinforced Composites as Engineered Structural Materials

    Dittenber, David B.

    The objective of this work was to provide a comprehensive evaluation of natural fiber reinforced polymer (NFRP)'s ability to act as a structural material. As a chemical treatment, aligned kenaf fibers were treated with sodium hydroxide (alkalization) in different concentrations and durations and then manufactured into kenaf fiber / vinyl ester composite plates. Single fiber tensile properties and composite flexural properties, both in dry and saturated environments, were assessed. Based on ASTM standard testing, a comparison of flexural, tensile, compressive, and shear mechanical properties was also made between an untreated kenaf fiber reinforced composite, a chemically treated kenaf fiber reinforced composite, a glass fiber reinforced composite, and oriented strand board (OSB). The mechanical properties were evaluated for dry samples, samples immersed in water for 50 hours, and samples immersed in water until saturation (~2700 hours). Since NFRPs are more vulnerable to environmental effects than synthetic fiber composites, a series of weathering and environmental tests were conducted on the kenaf fiber composites. The environmental conditions studied include real-time outdoor weathering, elevated temperatures, immersion in different pH solutions, and UV exposure. In all of these tests, degradation was found to be more pronounced in the NFRPs than in the glass FRPs; however, in nearly every case the degradation was less than 50% of the flexural strength or stiffness. Using a method of overlapping and meshing discontinuous fiber ends, large mats of fiber bundles were manufactured into composite facesheets for structural insulated panels (SIPs). The polyisocyanurate foam cores proved to be poorly matched to the strength and stiffness of the NFRP facesheets, leading to premature core shear or delamination failures in both flexure and compressive testing. The NFRPs were found to match well with the theoretical stiffness prediction methods of classical lamination

  11. Microhardness of resin composite materials light-cured through fiber reinforced composite.

    Fennis, W.M.M.; Ray, N.J.; Creugers, N.H.J.; Kreulen, C.M.


    OBJECTIVES: To compare polymerization efficiency of resin composite basing materials when light-cured through resin composite and fiber reinforced composite (FRC) by testing microhardness. METHODS: Simulated indirect restorations were prepared by application of resin composite (Clearfil AP-X) or FRC

  12. Microhardness of resin composite materials light-cured through fiber reinforced composite.

    Fennis, W.M.M.; Ray, N.J.; Creugers, N.H.J.; Kreulen, C.M.


    OBJECTIVES: To compare polymerization efficiency of resin composite basing materials when light-cured through resin composite and fiber reinforced composite (FRC) by testing microhardness. METHODS: Simulated indirect restorations were prepared by application of resin composite (Clearfil AP-X) or FRC



    According to the recent development trend and need of the friction brake material, the flake reinforced friction brake material has been made out by adjusting the recipe and techniques. The two-dimensional flake vermiculite is selected as the reinforced stuffing of the material; the modified resin is used as the basal bed of the material. The tests manifest that the properties of mechanics are high, the friction coefficients are suitable and stable,and especially in high temperatures the wear is low. It is an excellent friction brake material.

  14. Behavior of Fiber-Reinforced Smart Soft Composite Actuators According to Material Composition

    Han, Min-Woo; Kim, Hyung-Il; Song, Sung-Hyuk; Ahn, Sung-Hoon [Seoul Nat’l Univ., Seoul (Korea, Republic of)


    Fiber-reinforced polymer composites, which are made by combining a continuous fiber that acts as reinforcement and a homogeneous polymeric material that acts as a host, are engineering materials with high strength and stiffness and a lightweight structure. In this study, a shape memory alloy(SMA) reinforced composite actuator is presented. This actuator is used to generate large deformations in single lightweight structures and can be used in applications requiring a high degree of adaptability to various external conditions. The proposed actuator consists of numerous individual laminas of the glass-fiber fabric that are embedded in a polymeric matrix. To characterize its deformation behavior, the composition of the actuator was changed by changing the matrix material and the number of the glass-fiber fabric layers. In addition, current of various magnitudes were applied to each actuator to study the effect of the heating of SMA wires on applying current.

  15. Development of Ceramic Fibers for Reinforcement in Composite Materials

    Gates, L. E.; Lent, W. E.; Teague, W. T.


    the. testing apparatus for single fiber tensile strength increased the precision. of tests conducted on nine fibers. The highest mean tensile strength, a value of 295,000 pounds per square inch, was obtained with R-141 fibers. Treatment of R-74 fibers with anhydrous Linde A-1100 silane finish improved its mean fiber tensile strength by 25 percent. The lapse of time after fiber formation had no measurable effect on tensile strength. A static heating test conducted with various high melting fibers indicated that Fiberfrax and R-108 underwent no significant changes in bulk volume or resiliency on exposure to 2750 degrees Fahrenheit (1510 degrees Centigrade) in an oxidizing atmosphere. For fiber-resin composition fabrication, ten fiber materials were selected on the bases of high fiber yield, fusion temperature, and type of composition. Fiberfrax, a commercial ceramic fiber, was included for comparison. A new, more effective method of removing pellets from blown fibers was developed. The de-pelletized fibers were treated with a silane finish and felted into ten-inch diameter felts prior to resin impregnation. Composites containing 30 percent by weight of CTL 91-LD phenolic resin were molded under high pressure from the impregnated felts and post-cured to achieve optimum properties. Flexural strength, flexural modules of elasticity, and punch shear strength tests were conducted on the composite specimens. The highest average flexural strength obtained was 19,958 pounds per square inch with the R-74-fiber-resin composite. This compares very favorably with the military specification of 13,000 pounds per square inch flexural strength for randomly oriented fiber reinforced composites. The highest punch shear strength (11,509 pounds per square inch) was obtained with the R-89 fiber-resin composite. The effects of anhydrous fiber finishes on composite strength were not clearly indicated. Plasma arc tests at a heat flux of 550 British Thermal Units per square foot per second on

  16. Fabrication and properties of graphene reinforced silicon nitride composite materials

    Yang, Yaping; Li, Bin, E-mail:; Zhang, Changrui; Wang, Siqing; Liu, Kun; Yang, Bei


    Silicon nitride (Si{sub 3}N{sub 4}) ceramic composites reinforced with graphene platelets (GPLs) were prepared by hot pressed sintering and pressureless sintering respectively. Adequate intermixing of the GPLs and the ceramic powders was achieved in nmethyl-pyrrolidone (NMP) under ultrasonic vibration followed by ball-milling. The microstructure and phases of the Si{sub 3}N{sub 4} ceramic composites were investigated by Field Emission Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD). The effects of GPLs on the composites' mechanical properties were analyzed. The results showed that GPLs were well dispersed in the Si{sub 3}N{sub 4} ceramic matrix. β-Si{sub 3}N{sub 4,} O′-sialon and GPLs were present in the hot-pressed composites while pressureless sintered composites contain β-Si{sub 3}N{sub 4}, Si, SiC and GPLs. Graphene has the potential to improve the mechanical properties of both the hot pressed and pressureless sintered composites. Toughening effect of GPLs on the pressureless sintered composites appeared more effective than that on the hot pressed composites. Toughening mechanisms, such as pull-out, crack bridging and crack deflection induced by GPLs were observed in the composites prepared by the two methods.

  17. UV radiation effect towards mechanical properties of Natural Fibre Reinforced Composite material: A Review

    Mahzan, Shahruddin; Fitri, Muhamad; Zaleha, M.


    The use of natural fibres as reinforcement material have become common in human applications. Many of them are used in composite materials especially in the polymer matrix composites. The use of natural fibres as reinforcement also provide alternative solution of usage instead of being a waste materials. In some applications, these natural reinforced polymer composites were used as the outer layer, making them exposed to ultra violet exposure, hence prone to UV radiation. This paper reviews the effect of UV radiation towards the mechanical properties of natural fibre reinforced polymer matrix composite material. The effect of chemical treatment towards the natural fibre is also investigated. One of the important features that was critically explored was the degradation of the composite materials. The influence of UV radiation on the degradation rate involve several parameters such as wavelength, intensity and exposure time. This review highlights the influence of these parameters in order to provide better solution for polymer matrix composite’s development.

  18. Creep behavior of abaca fibre reinforced composite material

    Tobias, B.C.; Lieng, V.T. [Victoria Univ. of Technology, Victoria (Australia)


    This study investigates the creep behavior of abaca fibre reinforced composite lamina. The optimum proportions of constituents and loading conditions, temperature and stresses, are investigated in terms of creep properties. Lamina with abaca fibre volume fractions of 60, 70 and 80 percent, embedded in polyester resin were fabricated. Creep tests in tension at three temperature levels 20{degrees}C, 100{degrees}C and 120{degrees}C and three constant stress levels of 0. 1 MPa, 0. 13 Mpa and 0. 198 MPa using a Dynamic Mechanical Analyzer (DMA) were performed. The creep curves show standard regions of an ideal creep curve such as primary and secondary creep stage. The results also show that the minimum creep rate of abaca fibre reinforced composite increases with the increase of temperature and applied stress. Plotting the minimum creep rate against stress, depicts the variations of stress exponents which vary from 1.6194 at 20{degrees}C to 0.4576 at 120{degrees}C.

  19. Use of textile fibres in the reinforcement of a gypsum-cork based composite material

    Vasconcelos, Graça; Camões, Aires; Fangueiro, Raúl, ed. lit.; Vila-Chã, Nuno; Jesus, Carlos M. G.; Cunha, Fernando Eduardo Macedo


    The study presented herein focus on the analysis of a series of experimental tests aiming at characterizing the performance of distinct textile fibers acting as a reinforcement of a gypsum-cork composite material. Two groups of textile fibers were selected, namely synthetic fibers (glass and basalt) and natural fibers (banana and sisal). The reinforced composite material was submitted to distinct types of loading, namely compression tests, which it was possible to obtain the compressive stren...

  20. Study of erosion characterization of carbon fiber reinforced composite material

    Debnath, Uttam Kumar; Chowdhury, Mohammad Asaduzzaman; Kowser, Md. Arefin; Mia, Md. Shahin


    Carbon fiber composite materials are widely used at different engineering and industrial applications there are good physical, mechanical, chemical properties and light weight. Erosion behavior of materials depends on various factors such as impact angle, particle velocity, particle size, particle shape, particle type, particle flux, temperature of the tested materials. Among these factors impact angle and particle velocity have been recognized as two parameters that noticeably influence the erosion rates of all tested materials. Irregular shaped sand (SiO2) particles of various sizes (200-300 µm, 400-500 µm, and 500-600 µm) were selected erosive element. Tested conditions such as impingement angles between 15 degree to 90 degree, impact velocities between 30-50 m/sec, and stand-off distances 15-25 mm at surrounding room temperature were maintained. The highest level of erosion of the tested composite is obtained at 60° impact angle, which signifies the semi-ductile behavior of this material. Erosion showed increasing trend with impact velocity and decreasing nature in relation to stand-off distance. Surface damage was analyzed using SEM to examine the nature of the erosive wear mechanism.

  1. Potential of Carbon Nanotube Reinforced Cement Composites as Concrete Repair Material

    Tanvir Manzur


    Full Text Available Carbon nanotubes (CNTs are a virtually ideal reinforcing agent due to extremely high aspect ratios and ultra high strengths. It is evident from contemporary research that utilization of CNT in producing new cement-based composite materials has a great potential. Consequently, possible practical application of CNT reinforced cementitious composites has immense prospect in the field of applied nanotechnology within construction industry. Several repair, retrofit, and strengthening techniques are currently available to enhance the integrity and durability of concrete structures with cracks and spalling, but applicability and/or reliability is/are often limited. Therefore, there is always a need for innovative high performing concrete repair materials with good mechanical, rheological, and durability properties. Considering the mechanical properties of carbon nanotubes (CNTs and the test results of CNT reinforced cement composites, it is apparent that such composites could be used conveniently as concrete repair material. With this end in view, the applicability of multiwalled carbon nanotube (MWNT reinforced cement composites as concrete repair material has been evaluated in this study in terms of setting time, bleeding, and bonding strength (slant shear tests. It has been found that MWNT reinforced cement mortar has good prospective as concrete repair material since such composites exhibited desirable behavior in setting time, bleeding, and slant shear.

  2. Influence of composition on friction-wear behavior of composite materials reinforced by brass fibers

    JIA Xian; LING Xiaomei


    In the study, for the composite materials reinforced by brass fibers, the influence of dominant ingredients, such as organic adhesion agent, cast iron debris, brass fiber, and graphite powder, on the friction-wear characteristics was investigated. The friction-wear experiment was carried out on the block-on-ring tribometer MM200. The worn surfaces of the friction pair consisting of the composite materials and grey cast iron HT200 under dry sliding friction were examined using scanning electron microscope (SEM), energy dispersive analysis (EDX) and differential thermal analysis-thermogravimetric analysis (DTA-TAG). The experimental results showed that the friction coefficient and the wear loss of the composite material increase obviously with the increase of cast iron debris content, but decrease obviously with the increase of graphite powder content, and increase a little when the mass fraction of brass fiber was over 19%, and the orientation of brass fiber has obvious influence on friction-wear property. When the mass fraction of organic adhesion agent was about 10-11%, the composite materials have an excellent friction-wear performance. The friction heat can pyrolyze organic ingredient in worn surface layer.

  3. Effect of tool material on machinability of TiCp reinforced Al-1100 composite

    Harishchandra; Kadadevaramath, R. S.; Anil, K. C.


    In present days MMC's are widely used in most of the industries, like automobiles, aerospace, minerals and marine industries, because of its high specific strength to weight ratio. There are many types of reinforcements are available, selection of reinforcement is depends on availability, cost and desired reinforcement properties. In our study Al-1100 is selected as a primary material and Titanium carbide particle (TiCp) of 44 pm size as reinforcement and synthesized by manual stir casting method, by varying the reinforcement percentage. K2DF6 salt was used as wetting agent in order to improve the wetting behaviour of the reinforcement and same was observed in optical micrographs. Further, prepared composite materials are subjected to machinability studies by using lathe tool dynamometer in order to evaluate the cutting force, surface roughness with respect to reinforcement percentage and tool material. From the results, it is observed that the hardness and surface roughness of a specimen increases with the increasing of reinforcement percentage and Hardness of the tool material respectively.

  4. Resin Matrix/Fiber Reinforced Composite Material,Ⅲ:Simulating Results

    Li Chensha(李辰砂); Jiao Caishan; Liu Ying; Wang Zhengping; Wang Hongjie; Cao Maosheng


    According to the mathematical model which describes the curing process of composites constructed from continuous fiber-reinforced, thermosetting resin matrix prepreg materials, and the consolidation of the composite, the computer code calculates the data of the process variables of the flat-plate composites cured by a specified cure cycle, provides the variation of temperature distribution, the cure degree process, the resin variation and fibers stress inside the composite, the void variation and the residual stress distribution. The mechanism of curing process is illustrated and the cure cycle of composite material is optimized.

  5. Conifer fibers as reinforcing materials for polypropylene-based composites

    Plackett, David; Chengzhi, Chuai; Almdal, Kristoffer


    Conifer fibers were used to reinforce polypropylene (PP). To improve the compatibility between the conifer fibers and the PP matrix, the fibers were either grafted with maleated PP (MAPP), treated by adding MAPP, or mixed with ethylene/propylene/diene terpolymer (EPDM). The treatments resulted in...

  6. Mechanical, Spectroscopic and Micro-structural Characterization of Banana Particulate Reinforced PVC Composite as Piping Material

    B. Dan-asabe


    Full Text Available A banana particulate reinforced polyvinyl chloride (PVC composite was developed with considerabley low cost materials having an overall light-weight and good mechanical properties for potential application as piping material. The specimen composite material was produced with the banana (stem particulate as reinforcement using compression molding. Results showed that density and elastic Modulus of the composite decreases and increases respectively with increasing weight fraction of the particulate reinforcement. The tensile strength increased to a maximum of 42 MPa and then decreased steadily. The composition with optimum mechanical property (42 MPa was determined at 8, 62 and 30 % formulation of banana stem particulates (reinforcement, PVC (matrix and Kankara clay (filler respectively with corresponding percentage water absorption of 0.79 %, Young’s Modulus of 1.3 GPa, flexural strength of 92 MPa and density of 1.24 g/cm3. Fourier Transform Infrared (FTIR analysis of the constituents showed identical bands within the range 4000–1000 cm-1 with renown research work. Scanning Electron Microscopy (SEM result showed fairly uniform distribution of constituents’ phases. X-Ray Fluorescence (XRF confirms the X-ray diffraction (XRD result of the presence of minerals of kaolinite, quartz, rutile and illite in the kaolin clay. Comparison with conventional piping materials showed the composite offered a price savings per meter length of 84 % and 25 % when compared with carbon steel and PVC material.

  7. Strength and toughness of structural fibres for composite material reinforcement.

    Herráez, M; Fernández, A; Lopes, C S; González, C


    The characterization of the strength and fracture toughness of three common structural fibres, E-glass, AS4 carbon and Kevlar KM2, is presented in this work. The notched specimens were prepared by means of selective carving of individual fibres by means of the focused ion beam. A straight-fronted edge notch was introduced in a plane perpendicular to the fibre axis, with the relative notch depth being a0/D≈0.1 and the notch radius at the tip approximately 50 nm. The selection of the appropriate beam current during milling operations was performed to avoid to as much as possible any microstructural changes owing to ion impingement. Both notched and un-notched fibres were submitted to uniaxial tensile tests up to failure. The strength of the un-notched fibres was characterized in terms of the Weibull statistics, whereas the residual strength of the notched fibres was used to determine their apparent toughness. To this end, the stress intensity factor of a fronted edge crack was computed by means of the finite-element method for different crack lengths. The experimental results agreed with those reported in the literature for polyacrylonitrile-based carbon fibres obtained by using similar techniques. After mechanical testing, the fracture surface of the fibres was analysed to ascertain the failure mechanisms. It was found that AS4 carbon and E-glass fibres presented the lower toughness with fracture surfaces perpendicular to the fibre axis, emanating from the notch tip. The fractured region of Kevlar KM2 fibres extended along the fibre and showed large permanent deformation, which explains their higher degree of toughness when compared with carbon and glass fibres. This article is part of the themed issue 'Multiscale modelling of the structural integrity of composite materials'.

  8. Manufacturing Energy Intensity and Opportunity Analysis for Fiber-Reinforced Polymer Composites and Other Lightweight Materials

    Liddell, Heather; Brueske, Sabine; Carpenter, Alberta; Cresko, Joseph


    With their high strength-to-weight ratios, fiber-reinforced polymer (FRP) composites are important materials for lightweighting in structural applications; however, manufacturing challenges such as low process throughput and poor quality control can lead to high costs and variable performance, limiting their use in commercial applications. One of the most significant challenges for advanced composite materials is their high manufacturing energy intensity. This study explored the energy intensities of two lightweight FRP composite materials (glass- and carbon-fiber-reinforced polymers), with three lightweight metals (aluminum, magnesium, and titanium) and structural steel (as a reference material) included for comparison. Energy consumption for current typical and state-of-the-art manufacturing processes were estimated for each material, deconstructing manufacturing process energy use by sub-process and manufacturing pathway in order to better understand the most energy intensive steps. Energy saving opportunities were identified and quantified for each production step based on a review of applied R&D technologies currently under development in order to estimate the practical minimum energy intensity. Results demonstrate that while carbon fiber reinforced polymer (CFRP) composites have the highest current manufacturing energy intensity of all materials considered, the large differences between current typical and state-of-the-art energy intensity levels (the 'current opportunity') and between state-of-the-art and practical minimum energy intensity levels (the 'R&D opportunity') suggest that large-scale energy savings are within reach.

  9. Analysis and optimization of temperature distribution in carbon fiber reinforced composite materials during microwave curing process


    Vacuum assisted microwave curing technologies and modified optical sensing systems have been employed to investigate the influence of ply orientation and thickness on through-thickness temperature distribution of carbon fiber reinforced composite laminates. Two different types of epoxy systems have been studied. The results demonstrated that the ply orientation did not affect the temperature distribution of composite materials. However, the thickness was an important influencing factor. Nearl...

  10. Resin Matrix/Fiber Reinforced Composite Material, Ⅱ: Method of Solution and Computer Code

    Li Chensha(李辰砂); Jiao Caishan; Liu Ying; Wang Zhengping; Wang Hongjie; Cao Maosheng


    According to a mathematical model which describes the curing process of composites constructed from continuous fiber-reinforced, thermosetting resin matrix prepreg materials, and the consolidation of the composites, the solution method to the model is made and a computer code is developed, which for flat-plate composites cured by a specified cure cycle, provides the variation of temperature distribution, the cure reaction process in the resin, the resin flow and fibers stress inside the composite, the void variation and the residual stress distribution.

  11. Multiwalled carbon nanotube-reinforced ceramic matrix composites as a promising structural material

    Estili, Mehdi, E-mail: [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Department of Materials Processing, Graduate School of Engineering, Tohoku University, Sendai 980-8579 (Japan); Kwon, Hansang; Kawasaki, Akira; Cho, Seungchan; Takagi, Kenta; Kikuchi, Keiko [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Kawai, Masayoshi [Institute of Materials Structure Science, High Energy Accelerator Research Organization, Oho, Tsukuba, Ibaraki 305-0801 (Japan)


    In this paper, we introduce fully dense, multiwalled carbon nanotube (MWCNT)-reinforced ceramic matrix composites recently processed by a novel powder technology in our laboratory to be considered as a promising potential structural materials for employment in severe working conditions. A strategy is also offered to investigate the effect of working condition on the mechanical properties of MWCNTs embedded in the ceramic matrix for a reliable material selection for the working conditions needed.

  12. Impact test on natural fiber reinforced polymer composite materials

    D. Chandramohan


    Full Text Available In this research, natural fibers like Sisal (Agave sisalana, Banana (Musa sepientum & Roselle (Hibiscus sabdariffa , Sisal and banana (hybrid , Roselle and banana (hybrid and Roselle and sisal (hybrid are fabricated with bio epoxy resin using molding method. In this work, impact strength of Sisal and banana (hybrid, Roselle and banana (hybridand Roselle and sisal (hybrid composite at dry and wet conditions were studied. Impact test were conducted izod impact testing machine. In this work micro structure of the specimens are scanned by the Scanning Electron Microscope.

  13. Nanofiber reinforcement of a geopolymer matrix for improved composite materials mechanical performance

    Rahman, AKM Samsur

    Geopolymers have the potential to cross the process performance gap between polymer matrix and ceramic matrix composites (CMC), enabling high temperature capable composites that are manufactured at relatively low temperatures. Unfortunately, the inherently low toughness of these geopolymers limits the performance of the resulting fiber reinforced geopolymer matrix composites. Toughness improvements in composites can be addressed through the adjustments in the fiber/matrix interfacial strength and through the improvements in the inherent toughness of the constituent materials. This study investigates the potential to improve the inherent toughness of the geopolymer matrix material through the addition of nanofillers, by considering physical dimensions, mechanical properties, reinforcing capability and interfacial bond strength effects. A process optimization study was first undertaken to develop the ability to produce consistent, neat geopolymer samples, a critical precursor to producing nano-filled geopolymer for toughness evaluation. After that, single edge notched bend beam fracture toughness and un-notched beam flexural strength were evaluated for silicon carbide, alumina and carbon nanofillers reinforced geopolymer samples treated at various temperatures in reactive and inert environments. Toughness results of silicon carbide and carbon nanofillers reinforced geopolymers suggested that with the improved baseline properties, high aspect ratio nanofillers with high interfacial bond strength are the most capable in further improving the toughness of geopolymers. Among the high aspect ratio nanofillers i.e. nanofibers, 2vol% silicon carbide whicker (SCW) showed the highest improvement in fracture toughness and flexural strength of ~164% & ~185%, respectively. After heat treatment at 650 °C, SCW reinforcement was found to be effective, with little reduction in the performance, while the performance of alumina nanofiber (ANF) reinforced geopolymer significantly

  14. Selected mechanical properties of aluminum composite materials reinforced with SiC particles

    A. Kurzawa


    Full Text Available This work presents the results of research concerning influence of ceramic particles’ content of silicon carbide on selected mechanical properties of type AW-AlCu4Mg2Mn - SiC composite materials. Composites produced of SiC particles with pressure infiltration method of porous preform and subject to hot plastic forming in the form of open die forging were investigated. The experimental samples contained from 5% up to 45% of reinforcing SiC particles of 8÷10μm diameter. Studies of strength properties demonstrated that the best results, in case of tensile strength as well as offset yield strength, might be obtained while applying reinforcement in the amount of 20-25% vol. of SiC. Application of higher than 25% vol. contents of reinforcing particles leads to gradual strength loss. The investigated composites were characterized by very high functional properties, such as hardness and abrasive wear resistance, whose values increase strongly with the increase of reinforcement amount. The presented results of the experiments shall allow for a more precise component selection of composite materials at the stage of planning and design of their properties.

  15. Structural reinforcement of a {theta}16 inches tee made during operation with composite material

    Beim, Andre [Tresca Engenharia Ltda., Sao Paulo, SP (Brazil); Vilani, Eduardo Cesar [Rust Engenharia Ltda., Diadema, SP (Brazil)


    An industrial installation went through a turnaround to increase capacity. A tie-in line had to be made for this, and a 16 inches diameter branch was required to be made on an existing 16 inches pipe. The joining of these elements resulted in a 'tee' that was supposed to receive a reinforcement plate. This reinforcement plate was not installed before the plant start-up. Code calculations and a finite element stress analysis showed that reinforcement was necessary. The only viable solution was the application of a composite material reinforcement, designed to substitute the missing reinforcement plate, and reduce the stresses to allowable levels. A new finite element stress analysis was made to determine the required thickness of this reinforcement. The first part of this work shows the results of the finite element stress analysis. Figures with stress contours of the analyses show the results. The second part shows the details of the installation of the reinforcement, which was made during normal operation of the plant. Pictures illustrate the main steps of the installation procedure. (author)

  16. Effect of Fiber Waviness on Tensile Strength of a Flax-Sliver-Reinforced Composite Material

    Taweesak Piyatuchsananon


    Full Text Available Recently, a composite material made from natural fibers and biodegradable resin, “green composite,” is attracting attention as an alternative composite material for the replacement of glass fiber-reinforced plastics. Plant-based natural fibers such as kenaf and flax have already been used as composite reinforcement materials because they are more environmentally friendly and costless fibers than artificial fibers. A problem of using natural fibers is the fiber waviness, which affects the tensile properties. Fiber waviness is fluctuation in the fiber orientation that is inherent in the sliver morphology of plant-based natural fibers. This study was conducted to clarify the relation between quantified parameters of fiber waviness and a composite’s tensile strength. First, the fiber orientation angles on a flax-sliver-reinforced composite were measured. Then the angle distribution was quantified through spatial autocorrelation analysis methods: Local Moran’s I and Local Geary’s c. Finally, the relation between the resultant tensile strength and quantified parameters was discussed.

  17. Adherence of Streptococcus mutans to Fiber-Reinforced Filling Composite and Conventional Restorative Materials.

    Lassila, Lippo V J; Garoushi, Sufyan; Tanner, Johanna; Vallittu, Pekka K; Söderling, Eva


    OBJECTIVES.: The aim was to investigate the adhesion of Streptococcus mutans (S. mutans) to a short glass fibers reinforced semi-IPN polymer matrix composite resin. The effect of surface roughness on adhesion was also studied. For comparison, different commercial restorative materials were also evaluated. MATERIALS AND METHODS.: Experimental composite FC resin was prepared by mixing 22.5 wt% of short E-glass fibers, 22.5 wt% of IPN-resin and 55 wt% of silane treated silica fillers using high speed mixing machine. Three direct composite resins (Z250, Grandio and Nulite), resin-modified glass ionomers (Fuji II LC), amalgam (ANA 2000), fiber-reinforced composite (FRC) (everStick and Ribbond), and pre-fabricated ceramic filling insert (Cerana class 1) were tested in this study. Enamel and dentin were used as controls. The specimens (n=3/group) with or without saliva were incubated in a suspension of S. mutans allowing initial adhesion to occur. For the enumeration of cells on the disc surfaces as colony forming units (CFU) the vials with the microbe samples were thoroughly Vortex-treated and after serial dilutions grown anaerobically for 2 days at +37 degrees C on Mitis salivarius agars (Difco) containing bacitracin. Bacterial adhesion was also evaluated by using scanning electron microscopy. Surface roughness (Ra) of the materials was also determined using a surface profilometer. All results were statistically analyzed with one-way analysis of variance (ANOVA). RESULTS.: Composite FC resin and other commercial restorative materials showed similar adhesion of S. mutans, while adhesion to dentin and enamel was significantly higher (p<0.05). Surface roughness had no effect on bacterial adhesion. Saliva coating significantly decreased the adhesion for all materials (p<0.05). Composite FC resin had a significantly higher Ra value than control groups (p<0.05). CONCLUSIONS.: Short fiber-reinforced composite with semi-IPN polymer matrix revealed similar S. mutans adhesion




    Full Text Available La relación entre la geometría del entramado de las fibras y los mecanismos de fractura bajo cargas de tensión ha sido evaluada para materiales compuestos reforzados con textiles de diferente arquitectura tales como colchoneta (fibras al azar y petatillo (biaxial. Estos materiales están manufacturados empleando como matriz polimérica resina epóxica curada a altas temperaturas. El sistema elegido para este trabajo consiste en resina epóxica bifuncional diglicidil éter de bisfenol A (DGEBA curada con una amina tetrafuncional diaminodifenil sulfona (DDS. Este sistema asegura la obtención de un material rígido transparente con excelentes propiedades mecánicas que permite observar, analizar e identificar el proceso y el progreso del daño generado así como los mecanismos de fractura que conllevan a la ruptura del material. Los resultados demostraron que la arquitectura/geometría de los textiles de refuerzo influye en la generación de sitios de concentración de esfuerzos donde se incrementa la posibilidad de iniciación de fallas y la propagación de grietas.

  19. Processing and Material Characterization of Continuous Basalt Fiber Reinforced Ceramic Matrix Composites Using Polymer Derived Ceramics.

    Cox, Sarah B.


    The need for high performance vehicles in the aerospace industry requires materials which can withstand high loads and high temperatures. New developments in launch pads and infrastructure must also be made to handle this intense environment with lightweight, reusable, structural materials. By using more functional materials, better performance can be seen in the launch environment, and launch vehicle designs which have not been previously used can be considered. The development of high temperature structural composite materials has been very limited due to the high cost of the materials and the processing needed. Polymer matrix composites can be used for temperatures up to 260C. Ceramics can take much higher temperatures, but they are difficult to produce and form in bulk volumes. Polymer Derived Ceramics (PDCs) begin as a polymer matrix, allowing a shape to be formed and cured and then to be pyrolized in order to obtain a ceramic with the associated thermal and mechanical properties. The use of basalt in structural and high temperature applications has been under development for over 50 years, yet there has been little published research on the incorporation of basalt fibers as a reinforcement in the composites. In this study, continuous basalt fiber reinforced PDCs have been fabricated and tested for the applicability of this composite system as a high temperature structural composite material. The oxyacetylene torch testing and three point bend testing have been performed on test panels and the test results are presented.

  20. Particulate Filled Composite Plastic Materials from Recycled Glass Fibre Reinforced Plastics

    Aare ARUNIIT


    Full Text Available Glass fibre reinforced plastic (GFRP scrap consisted of acrylic plastic with glass fibre reinforcement in polyester resin matrix was used in our experiments. The multi-functional DS-series disintegrator mills were used for mechanical processing of GFRP scrap. Preceding from the results characterization of the milled powder particles size, shape and other properties the numerical algorithm for modelling of the density of the new filler material was developed. The main goal of the current study is to develop new particulate filled composite plastic material from recycled GFRP scrap. With recovered plastic powder material the higher filler content in polyester resin matrix can be achieved. The new composite is modelled on basis of the properties of new material. Such an approach requires tests of the new material. The considered target characteristics of the new material are the tensile strength, elongation at break and the cost. The multicriteria optimization problem has been formulated and solved by use of physical programming techniques and Pareto optimality concept. The designed new composites were manufactured in different mixing ratios of powder and binder agent. The strength and stiffness properties of new composite material were tested.

  1. Design and analysis of a novel latch system implementing fiber-reinforced composite materials

    Guevara Arreola, Francisco Javier

    The use of fiber-reinforced composite materials have increased in the last four decades in high technology applications due to their exceptional mechanical properties and low weight. In the automotive industry carbon fiber have become popular exclusively in luxury cars because of its high cost. However, Carbon-glass hybrid composites offer an effective alternative to designers to implement fiber-reinforced composites into several conventional applications without a considerable price increase maintaining most of their mechanical properties. A door latch system is a complex mechanism that is under high loading conditions during car accidents such as side impacts and rollovers. Therefore, the Department of Transportation in The United States developed a series of tests that every door latch system comply in order to be installed in a vehicle. The implementation of fiber-reinforced composite materials in a door latch system was studied by analyzing the material behavior during the FMVSS No. 206 transverse test using computational efforts and experimental testing. Firstly, a computational model of the current forkbolt and detent structure was developed. Several efforts were conducted in order to create an effective and time efficient model. Two simplified models were implemented with two different contact interaction approaches. 9 composite materials were studied in forkbolt and 5 in detent including woven carbon fiber, unidirectional carbon fiber, woven carbon-glass fiber hybrid composites and unidirectional carbon-glass fiber hybrid composites. The computational model results showed that woven fiber-reinforced composite materials were stiffer than the unidirectional fiber-reinforced composite materials. For instance, a forkbolt made of woven carbon fibers was 20% stiffer than a forkbolt made of unidirectional fibers symmetrically stacked in 0° and 90° alternating directions. Furthermore, Hybrid composite materials behaved as expected in forkbolt noticing a decline

  2. Modeling of Stress Development During Thermal Damage Healing in Fiber-reinforced Composite Materials Containing Embedded Shape Memory Alloy Wires

    Bor, Teunis Cornelis; Warnet, Laurent; Akkerman, Remko; de Boer, Andries


    Fiber-reinforced composite materials are susceptible to damage development through matrix cracking and delamination. This article concerns the use of shape memory alloy (SMA) wires embedded in a composite material to support healing of damage through a local heat treatment. The composite material

  3. Modeling of Stress Development During Thermal Damage Healing in Fiber-reinforced Composite Materials Containing Embedded Shape Memory Alloy Wires

    Bor, T.C.; Warnet, L.; Akkerman, R.; Boer, de A.


    Fiber-reinforced composite materials are susceptible to damage development through matrix cracking and delamination. This article concerns the use of shape memory alloy (SMA) wires embedded in a composite material to support healing of damage through a local heat treatment. The composite material co

  4. Determination of Material Parameters for Microbuckling Analysis of Fiber Reinforced Polymer Matrix Composites

    Romanowicz M.


    Full Text Available This research focuses on studying the effect of the constitutive law adopted for a matrix material on the compressive response of a unidirectional fiber reinforced polymer matrix composite. To investigate this effect, a periodic unit cell model of a unidirectional composite with an initial fiber waviness and inelastic behavior of the matrix was used. The sensitivity of the compressive strength to the hydrostatic pressure, the flow rule and the fiber misalignment angle were presented. The model was verified against an analytical solution and experimental data. Results of this study indicate that a micromechanical model with correctly identified material parameters provides a useful alternative to theoretical models and experimentation.

  5. Determination of Material Parameters for Microbuckling Analysis of Fiber Reinforced Polymer Matrix Composites

    Romanowicz, M.


    This research focuses on studying the effect of the constitutive law adopted for a matrix material on the compressive response of a unidirectional fiber reinforced polymer matrix composite. To investigate this effect, a periodic unit cell model of a unidirectional composite with an initial fiber waviness and inelastic behavior of the matrix was used. The sensitivity of the compressive strength to the hydrostatic pressure, the flow rule and the fiber misalignment angle were presented. The model was verified against an analytical solution and experimental data. Results of this study indicate that a micromechanical model with correctly identified material parameters provides a useful alternative to theoretical models and experimentation.

  6. Application of cold plasma technology in fiber-reinforced composite materials


    A study is presented concerning a cold plasma technique for improving the bondability of highstrength high-modulus multi-filament polyethylene fibers to polymer matrices and the fibers impregnation with the objective to fabricate composite materials (CMs). Strong bonding between the matrixes and reinforcing fibers during the production of composites appears in the case if interaction is chemical. The value of the activation energy of the chemical interaction for very high performance polyethylene fiber was estimated. It was 1.14 eV. This allows using the cold plasma technique for producing CMs. In order to understand the effect of cold plasma treatment treated and untreated fibers were used to fabricate CMs. The strong bond between the matrix and plasma-activated fibers affects both the properties and failure mode of composite. The properties and failure modes were compared to those of CMs reinforced with untreated fibers. After plasma treatment the properties of CMs are increased. CMs are broken as a unit whole under tension. The ideas of the activating the fibers by cold plasma treatment above the activation energy of the chemical interaction may be extended over other types of the fibers and matrices to produce new types of fiber-reinforced composite materials with high physicomechanical indices.

  7. Corn gluten meal as a biodegradable matrix material in wood fibre reinforced composites

    Beg, M.D.H. [Department of Materials and Process Engineering, University of Waikato, Private Bag 3105, Hamilton (New Zealand); Pickering, K.L. [Department of Materials and Process Engineering, University of Waikato, Private Bag 3105, Hamilton (New Zealand)]. E-mail:; Weal, S.J. [Department of Materials and Process Engineering, University of Waikato, Private Bag 3105, Hamilton (New Zealand)


    This study was undertaken to investigate corn gluten meal (CGM) as a biodegradable matrix material for wood fibre reinforced composites. CGM was used alone, as well as hybridized with polypropylene, and reinforced with radiata pine (Pinus Radiata) fibre using a twin-screw extruder followed by injection moulding. Tensile testing, scanning electron microscopy and differential scanning calorimetry were carried out to assess the composites. For composites from CGM and wood fibres, extrusion was carried out with the aid of the following plasticizers: octanoic acid, glycerol, polyethylene glycol and water. Windows of processability for the different plasticizers were obtained for all plasticizers. These were found to lie between 20 and 50 wt.% of plasticizer with a maximum of approximately 20% wood fibre reinforcement. The best mechanical properties were obtained with a matrix containing 10 wt.% octanoic acid and 30 wt.% water, which gave a tensile strength and Young's modulus of 18.7 MPa and 4 GPa, respectively. Hybrid matrix composites were compounded with a maleated polypropylene coupling agent and benzoyl peroxide as a cross-linking agent. The highest tensile strength and Young's modulus obtained from hybrid matrix composites were 36.9 MPa and 5.8 GPa with 50 wt.% fibre.

  8. Study of the Effect of Reinforced Glass Fibers on Fatigue Properties for Composite Materials

    Mohamed G. Hamad


    Full Text Available This  research  included  the  study of  the effect  of  reinforced  glass fibers  on  fatigue  properties  for composite materials. Polyester  resin  is used  as  connective  material(matrix in two types  of  glass  fibers  for reinforced. The  first  type  is regular  glass fibers  (woven  roving with the  directional(0-90, the second  is  glass  fibers  with  the  random  direction. The first type is the panels with regular reinforced (0-90, and with number of layer (1,2.The  second  type  is  the  panels with random  reinforced  and  with  number  of  layers (1,2. The  results  and  the  laboratory  examinations  for  the samples  reinforce  with  fibers  have  manifested (0-90  that there  is  a decrease  in the number  of  cycles  to the  fatigue  limit  when  the  number  of  reinforce  layers  have  increased . And  an elasticity of this  type  of  samples  are decreased  by  increasing  the number  of  reinforced  layers  with  fiber  .We  find  the  random  reinforced  number  of  fatigue  cycles  for the samples  with  two  layers  of  random  reinforced  are  decreased  more  than the samples  with  one  layer of random  reinforced .

  9. Railgun Application for High Energy Impact Testing of Nano-Reinforced Kevlar-Based Composite Materials

    Micheli, D.; Vricella, A.; Pastore, R.; Morles, R. B.; Marchetti, M.


    An advanced electromagnetic accelerator, called railgun, has been assembled and tuned in order to perform high energy impact test on layered structures. Different types of layered composite materials have been manufactured and characterized in terms of energy absorbing capability upon impact of metallic bullets fired at high velocity. The composite materials under testing are manufactured by integrating several layers of Kevlar fabric and carbon fiber ply within a polymeric matrix reinforced by carbon nanotubes at 1% of weight percentage. The experimental results show that the railgun-device is a good candidate to perform impact testing of materials in the space debris energy range, and that carbon nanotubes may enhance, when suitably coupled to the composite's matrix, the excellent antiballistic properties of the Kevlar fabrics.

  10. Aspects regarding wearing behaviour in case of aluminium composite materials reinforced with carbon fibers

    Caliman, R.


    This paper presents a study regarding wear comportment of sintered composite materials obtained by mixture of aluminium with short carbon fibers. The necessity to satisfying more and more the specific functions during design of high performance structures leads to perform multi-materials such as reinforced composite parts. The wear tests were made on three different orientations of fibers on a standard machine of tribology, pin disk type. Counter-disk was made of cast iron with a superficial hardness of 92 HB. The wear rate and friction coefficient decreased exponentially with time of friction and reached a stationary value. This behaviour was attributed to the development of a lubricating film on the friction surface. To conduct this work was performed measurements on samples from the Al matrix composites and carbon fiber 43%, wear mechanism was investigated by scanning electron microscopy. In addition to fiber orientation, the tribological behaviour of metal matrix composites reinforced with fiber is influenced by the interfacial reaction of fiber-matrix. The characteristics and the dimensions of the interface depend on the cycle of temperature and time at which the material has been subjected during the manufacturing process and thereafter.

  11. Tribological properties of metal-matrix composite materials reinforced by superelastic hard carbon particles

    Ushakova, I. N.; Drozdova, E. I.; Chernogorova, O. P.; Blinov, V. M.; Ekimov, E. A.


    Metal-matrix composite materials (CMs) are synthesized from a mixture of a metal powder (Ti, Fe, Co, Ni, Cu, Al-based alloy) and fullerenes (10 wt %). The thermobaric synthesis conditions (700-1000°C, 5-8 GPa) ensure the collapse of fullerene molecules and their transformation into superelastic carbon phase particles with an indentation hardness H IT = 10-37 GPa, an elastic modulus E IT = 60-260 GPa, and an elastic recovery of >80% upon indentation. After reinforcing by superelastic hard carbon, the friction coefficient of CM decreases by a factor of 2-4 as compared to the friction coefficient of the matrix metal, and the abrasive wear resistance increases by a factor of 4-200. Superelastic hard carbon particles are a unique reinforcing material for an increase in the wear resistance and a simultaneous decrease in the friction coefficient of CM.

  12. Pineapple leaf fiber as reinforce in composite materials, an alternative for automotive industry

    Campos, Rejane Daniela de; Seo, Emilia Satoshi Miyamaru, E-mail: [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)


    The composites appear as an extremely favorable alternative for different industries, due to the fact that it combines the best mechanical properties with the best physic-chemical properties of two or more materials. Nowadays, in the evaluation of materials, besides criteria such as economic viability and performance, the environmental criterion was included in this evaluation. Part of the environmental criteria is the use of biodegradable materials and/or recycled materials. In this sense, researches focused on vegetal fibers, as reinforcement in composites are growing considerably and positive results for its performance were achieved. Moreover, the environmental-friendly approach not only is the unique advantage on usage of vegetal fibers, but also it has an economical advantage, because of the low cost and good performance due to low density. The fiber extracted from the pineapple leaf (PALF) is a new alternative for automotive industry as cellulose-based fiber composite. In this sense, the present paper aims to present the characterization of the pineapple leaf fiber for manufacturing the automotive composite materials. Milled pineapple fibers extracted, in two different ways and submitted to mercerisation treatments, were characterized by mechanical and thermal properties; density; morphology; FTIR spectroscopy, EDX and X-ray diffraction. It is important to characterize the fibers, in order to obtain appropriate mechanical properties of composite. (author)

  13. The importance of material structure in the laser cutting of glass fiber reinforced plastic composites

    Caprino, G. (Univ. di Napoli (Italy). Dipt. di Ingegneria dei Materiali e della Produzione); Tagliaferri, V. (Univ. di Salerno (Italy). Istituto di Ingegneria Meccanica); Covelli, L. (IMU-Consiglio Nazionale delle Ricerche, Milano (Italy))


    A previously proposed micromechanical formula, aiming to predict the vaporization energy Q[sub v] of composite materials as a function of fiber and matrix properties and fiber volume ratio, was assessed. The experimental data, obtained on glass fiber reinforced plastic panels with different fiber contents cut by a medium power CO[sub 2] cw laser, were treated according to a procedure previously suggested, in order to evaluate Q[sub v]. An excellent agreement was found between experimental and theoretical Q[sub v] values. Theory was then used to predict the response to laser cutting of a composite material with a fiber content varying along the thickness. The theoretical predictions indicated that, in this case, the interpretation of the experimental results may be misleading, bringing to errors in the evaluation of the material thermal properties, or in the prediction of the kerf depth. Some experimental data were obtained, confirming the theoretical findings.

  14. Fracture mechanics in fiber reinforced composite materials, taking as examples B/A1 and CRFP

    Peters, P. W. M.


    The validity of linear elastic fracture mechanics and other fracture criteria was investigated with laminates of boron fiber reinforced aluminum (R/A1) and of carbon fiber reinforced epoxide (CFRP). Cracks are assessed by fracture strength Kc or Kmax (critical or maximum value of the stress intensity factor). The Whitney and Nuismer point stress criterion and average stress criterion often show that Kmax of fiber composite materials increases with increasing crack length; however, for R/A1 and CFRP the curve showing fracture strength as a function of crack length is only applicable in a small domain. For R/A1, the reason is clearly the extension of the plastic zone (or the damage zone n the case of CFRP) which cannot be described with a stress intensity factor.


    曾鸣; 丁博; 郭梦熊


    By means of whisker reinforce and paricle dispersion, the routes of property improvement on Si3N4 ceramic material have been studied. The mecihaniacl properties of Siw/Si3N4 and Siw/Si3N4TiC material was compared, which proved that multiphase reinforce had overlap effect. Microstructure of the material was investigated by means of SEM and the mechanisms of SiCw and TiCP reinforces had been disussed.

  16. Standard Guide for Recording Mechanical Test Data of Fiber-Reinforced Composite Materials in Databases

    American Society for Testing and Materials. Philadelphia


    1.1 This guide provides a common format for mechanical test data for composite materials for two purposes: (1) to establish data reporting requirements for test methods and ( 2) to provide information for the design of material property databases. This guide should be used in combination with Guide E 1309 which provides similar information to identify the composite material tested. 1.2 These guidelines are specific to mechanical tests of high-modulus fiber-reinforced composite materials. Types of tests considered in this guide include tension, compression, shear, flexure, open/filled hole, bearing, fracture toughness, and fatigue. The ASTM standards for which this guide was developed are listed in . The guidelines may also be useful for additional tests or materials. 1.3 This guide is the second part of a modular approach for which the first part is Guide E 1309. Guide E 1309 serves to identify the material, and this guide serves to describe mechanical testing procedures and variables and to record results....

  17. Evaluation of mechanical properties of natural hybrid fibers, reinforced polyester composite materials

    S. Kasiviswanathan


    Full Text Available The composite materials are replacing the traditional materials, because of its superior properties such as high tensile strength, low thermal expansion, high strength to weight ratio. The developments of new materials are on the anvil and are growing day by day. In this work the effect of glass fibre hybridization with the randomly oriented natural fibers has been evaluated. The sisal (S, banana (B, E-glass synthetic fibers were chopped and reinforced with polyester matrix. Six layers were prepared in the following stacking sequence of S/B/G, S/G/B, G/S/B, G/S/B/G/S/B/G, S/G/B//S/G/B, B/G/S/B/G/S. The mechanical properties like impact strength, flexural strength and tensile strength were investigated and compared. It was observed that the addition of two and three layer of glass fiber can improve the mechanical properties like tensile, Flexural and impact strength.

  18. Standard Guide for Identification of Fiber-Reinforced Polymer-Matrix Composite Materials in Databases

    American Society for Testing and Materials. Philadelphia


    1.1 This guide establishes essential and desirable data elements for fiber-reinforced composite materials for two purposes: to establish the material identification component of data-reporting requirements for test reporting and to provide information for the design of material property databases. 1.1.1 This guide is the first part of a two-part modular approach. The first part serves to identify the material and the second part serves to describe testing procedures and variables and to record results. 1.1.2 For mechanical testing, the related document is Guide E 1434. The interaction of this guide with Guide E 1434 is emphasized by the common numbering of data elements. Data Elements A1 through G13 are included in this guide, and numbering of data elements in Guide E 1434 begins with H1 for the next data element block. This guide is most commonly used in combination with a guide for reporting the test procedures and results such as Guide E 1434. 1.2 These guidelines are specific to fiber-reinforced polyme...

  19. Carbon nanotube-based structural health monitoring for fiber reinforced composite materials

    Liu, Hao; Liu, Kan; Mardirossian, Aris; Heider, Dirk; Thostenson, Erik


    In fiber reinforced composite materials, the modes of damage accumulation, ranging from microlevel to macro-level (matrix cracks development, fiber breakage, fiber-matrix de-bonding, delamination, etc.), are complex and hard to be detected through conventional non-destructive evaluation methods. Therefore, in order to assure the outstanding structural performance and high durability of the composites, there has been an urgent need for the design and fabrication smart composites with self-damage sensing capabilities. In recent years, the macroscopic forms of carbon nanotube materials have been maturely investigated, which provides the opportunity for structural health monitoring based on the carbon nanotubes that are integrated in the inter-laminar areas of advanced fiber composites. Here in this research, advanced fiber composites embedded with laminated carbon nanotube layers are manufactured for damage detection due to the relevant spatial electrical property changes once damage occurs. The mechanical-electrical coupling response is recorded and analyzed during impact test. The design and manufacturing of integrating the carbon nanotubes intensely affect the detecting sensitivity and repeatability of the integrated multifunctional sensors. The ultimate goal of the reported work is to develop a novel structural health monitoring method with the capability of reporting information on the damage state in a real-time way.

  20. Treatments of non-wood plant fibres used as reinforcement in composite materials

    Marie-Ange Arsène


    Full Text Available This paper presents a summary of the knowledge on fibres and pulps of non wood tropical plants used as reinforcement in cementitious composites accumulated during the recent years by Guadeloupean and Brazilian teams participating in collaborative work. Vegetable fibres represent a good alternative as non-conventional materials for the construction of ecological and sustainable buildings. The use of such renewable resources contributes to the development of sustainable technologies. The main objective of the paper is to emphasize the use of agricultural wastes in the production of cement based composites. The botanical, chemical, physical, morphological and mechanical properties of fibres from various plants are described. The effects of different treatments on physical, chemical and mechanical properties of fibres are presented. The most effective treatments in influencing the mechanical and physical properties are pyrolysis and alkaline ones, according to the type of plant. The final choice will have to consider fibre availability, and treatment costs.

  1. Neutron scattering as a probe of liquid crystal polymer-reinforced composite materials

    Hjelm, R.P.; Douglas, E.P.; Benicewicz, B.C.; Langlois, D.A.


    This is the final report of a three-year Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). This research project sought to obtain nanoscale and molecular level information on the mechanism of reinforcement in liquid crystal polymer (LCP)-reinforced composites, to realize molecular-reinforced LCP composites, and to test the validity of the concept of molecular reinforcement. Small-angle neutron scattering was used to study the structures in the ternary phase diagram of LCP with liquid crystal thermosets and solvent on length scales ranging from 1-100 nm. The goal of the scattering measurements is to understand the phase morphology and degree of segregation of the reinforcing and matrix components. This information helps elucidate the physics of self assembly in these systems. This work provides an experimental basis for a microengineering approach to composites of vastly improved properties.

  2. Study on dry friction and wear resistance of a WC-Co particle reinforced iron matrix composite material

    Zhang Peng; Zeng Shaolian; Zhang Zhiguo


    In order to select a suitable material for the rolling mill guide application, the dry sliding friction and wear resistance of a tungsten carbide combining cobalt (WC-Co) particle reinforced chromium cast iron composite material were studied. In particular, the wear resistance was discussed in detail. The results showed that the composite material demonstrates 25 times the wear resistance of high Cr cast iron, and 9 times the wear resistance of heat resistant steel. However, the average frict...

  3. Compression Molding of Chemical/Thermal Resistant Composite Materials Using Wastes of Glass Fiber Reinforced PTFE and Carbon Fiber

    Kimura, Teruo


    This report proposed the compression molding method of chemical/thermal resistant composite materials reinforced by the carbon fiber extracted from CFRP waste and the waste of glass fiber coated by PTFE. The FEP resin was used for the matrix material. The contents of carbon fiber and FEP resin were varied in the experiments, and the machanical properties of composite materials were discussed in detail. As a result, the bending strength and modulus increased with increasing the content of carb...

  4. Composite Materials

    Nielsen, Lauge Fuglsang

    This book deals with the mechanical and physical behavior of composites as influenced by composite geometry. "Composite Materials" provides a comprehensive introduction for researchers and students to modern composite materials research with a special emphasis on the significance of phase geometry....... The book enables the reader to a better understanding of the behavior of natural composites, improvement of such materials, and design of new materials with prescribed properties. A number of examples are presented: Special composite properties considered are stiffness, shrinkage, hygro-thermal behavior...... materials. Numerical procedures are outlined which facilitate the practical analysis of any feature considered in this book. Examples are presented which illustrate the analysis of well-known materials such as concrete, hardening cement paste, ceramics, tile, wood, impregnated and reinforced materials...

  5. Study of stinging nettle (urtica dioica l.) Fibers reinforced green composite materials : a review

    Agus Suryawan, I. G. P.; Suardana, N. P. G.; Suprapta Winaya, I. N.; Budiarsa Suyasa, I. W.; Tirta Nindhia, T. G.


    Stinging Nettle (Urtica dioica L., latin) is a wild plant that grows in Indonesia, Asia, and Europe. Nettle in Bali, Indonesia is called as Lateng, Jelatang. Nettle plant has a very strong fiber and high fixed carbon. Nettle plants are covered with fine hairs, especially in the leaves and stems. When it is touched, it will release chemicals, sting and trigger inflammation that causes redness, itching, bumps and irritation to the skin. Nettle plants grow in the wild, regarded as a weed in the agricultural industry, easy to grow and snatch food from the parent plant. The main objective of this paper is to review of the potential nettle fibers and then explain about the potential of local nettle plant in Indonesia. Nettle is a plant group at the end of bast. Its plant fibers taken from the bark, as reinforcement in composite materials. Nettle fibers have three main advantages such as strong, lightweight and low environmental impact.

  6. Experimental data on the properties of natural fiber particle reinforced polymer composite material

    D. Chandramohan


    Full Text Available This paper presents an experimental study on the development of polymer bio-composites. The powdered coconut shell, walnut shells and Rice husk are used as reinforcements with bio epoxy resin to form hybrid composite specimens. The fiber compositions in each specimen are 1:1 while the resin and hardener composition 10:1 respectively. The fabricated composites were tested as per ASTM standards to evaluate mechanical properties such as tensile strength, flexural strength, shear strength and impact strength are evaluated in both with moisture and without moisture. The result of test shows that hybrid composite has far better properties than single fibre glass reinforced composite under mechanical loads. However it is found that the incorporation of walnut shell and coconut shell fibre can improve the properties.

  7. Experimental Investigation of Effect of Aluminum Filler Material on Thermal Properties of Palmyra Fiber Reinforced Composite

    J. Pavanu Sai


    Full Text Available Natural fiber composites are renewable, cheap, completely or partially recyclable, carbon neutral and biodegradable. Their easy availability, lower density, higher specific properties, lower cost, satisfactory mechanical and thermal properties, non-corrosive nature, lesser abrasion to processing equipment, makes them an attractive ecological alternative to glass, carbon or other man-made synthetic fibers. Natural fiber composites are generally very good thermal insulators and thus cannot be used where thermal conduction is desirable. Increase in thermal conduction may be done by adding metal filler powders to the matrix. In this work, the effect of aluminum filler material on thermal properties of chemically treated palmyra fiber reinforced composites is investigated. Thermal properties studied include thermal conductivity, specific heat capacity, thermal diffusivity, thermal degradation and stability. Five different samples with 0%, 25%, 50%, 75%, 100% aluminum powder are considered. With the addition of aluminum filler powder, thermal conductivity increases, specific heat capacity decreases, thermal diffusivity increases and thermal stability improves with maximum at 50% aluminum powder.

  8. Macro-mechanical material model for fiber reinforced metal matrix composites

    Banks-Sills, L


    The stress-strain behavior of a metal matrix composite reinforced with unidirectional, continuous and periodic fibers is investigated. Three-dimensional micro-mechanical analyses of a unit cell by means of the finite element method $9 and homogenization-localization are carried out. These calculations allow the determination of material behavior of the in-plane, as well as the fiber directions. The fibers are assumed to be elastic and the matrix elasto-plastic. $9 The matrix material is governed by a von Mises yield surface, isotropic hardening and an associated flow rule. With the aid of these analyses, the foundation to a macro-mechanical material model is presented which is employed to $9 consider an elementary problem. The model includes an anisotropic yield surface with isotropic hardening and an associated flow rule. A beam in bending containing square fibers under plane strain conditions is analyzed by means of $9 the model. Two cases are considered: one in which the fibers are symmetric with respect t...

  9. Technical features and criteria in designing fiber-reinforced composite materials: from the aerospace and aeronautical field to biomedical applications.

    Gloria, Antonio; Ronca, Dante; Russo, Teresa; D'Amora, Ugo; Chierchia, Marianna; De Santis, Roberto; Nicolais, Luigi; Ambrosio, Luigi


    Polymer-based composite materials are ideal for applications where high stiffness-to-weight and strength-to-weight ratios are required. From aerospace and aeronautical field to biomedical applications, fiber-reinforced polymers have replaced metals, thus emerging as an interesting alternative. As widely reported, the mechanical behavior of the composite materials involves investigation on micro- and macro-scale, taking into consideration micromechanics, macromechanics and lamination theory. Clinical situations often require repairing connective tissues and the use of composite materials may be suitable for these applications because of the possibility to design tissue substitutes or implants with the required mechanical properties. Accordingly, this review aims at stressing the importance of fiber-reinforced composite materials to make advanced and biomimetic prostheses with tailored mechanical properties, starting from the basic principle design, technologies, and a brief overview of composites applications in several fields. Fiber-reinforced composite materials for artificial tendons, ligaments, and intervertebral discs, as well as for hip stems and mandible models will be reviewed, highlighting the possibility to mimic the mechanical properties of the soft and hard tissues that they replace.

  10. An Investigation of Stimulating the Autoclave Curing Process of Resin Matrix/Fiber Reinforced Composite Material,Ⅰ: Process model


    A mathematical model is made which describes the curing process of composites constructed from continuous fiber-reinforced, thermosetting resin matrix prepreg materials, and the consolidation of the composite is developed. The model provides the variation of temperature distribution, the cure reaction process in the resin, the resin flow and fibers stress inside the composite, and the void variation and the residual stress distribution. It can be used to illustrate the mechanism of curing process and optimize the cure cycle of composite material in order to ensure the quality of a product.

  11. The Impact of Methods of Forming on the Mechanical Properties of Fiber-reinforced Polymer-matrix Composite Materials

    Piernik Krzysztof


    Full Text Available The aim of this paper was to analyze how different techniques of production of fibrous composite materials affect the quality and strength properties of composite laminates. In this study, we use experimental data concerning a composite fabricated with the by hand lay-up and vacuum bagging method. The composites have a polyester matrix (Firestop 8175-w-1 reinforced with mate-glass fiber fabric [0/90/0/90] E glass fiber, respectively. The process parameters and criteria were determined before the samples were cut, namely the amount and soaking time of the composite with the polymer resin.

  12. Study on dry friction and wear resistance of a WC-Co particle reinforced iron matrix composite material

    Zhang Peng


    Full Text Available In order to select a suitable material for the rolling mill guide application, the dry sliding friction and wear resistance of a tungsten carbide combining cobalt (WC-Co particle reinforced chromium cast iron composite material were studied. In particular, the wear resistance was discussed in detail. The results showed that the composite material demonstrates 25 times the wear resistance of high Cr cast iron, and 9 times the wear resistance of heat resistant steel. However, the average friction factor in the stable friction stage showed a relationship of μComposites/45 # steel > μHigh chromium cast iron/45 # steel > μHeat resistant steel/45 # steel. The wear resistance mechanism of the composite material was associated with the reinforcing particles, which protruded from the worn surface to bear the friction load when the matrix material surface was worn, thereby reducing the abrasive and adhesive wear. In addition, the matrix material possessed suitable hardness and toughness, providing a support to the reinforcements.

  13. Evaluation of the Biocompatibility of New Fiber-Reinforced Composite Materials for Craniofacial Bone Reconstruction.

    Lazar, Mădălina-Anca; Rotaru, Horaţiu; Bâldea, Ioana; Boşca, Adina B; Berce, Cristian P; Prejmerean, Cristina; Prodan, Doina; Câmpian, Radu S


    This study aims to assess the biocompatibility of new advanced fiber-reinforced composites (FRC) to be used for custom-made cranial implants. Four new formulations of FRC were obtained using polymeric matrices (combinations of monomers bisphenol A glycidylmethacrylate [bis-GMA], urethane dimethacrylate [UDMA], triethylene glycol dimethacrylate [TEGDMA], hydroxyethyl methacrylate [HEMA]) and E-glass fibers (300 g/mp). Every FRC contains 65% E-glass and 35% polymeric matrix. Composition of polymeric matrices are: bis-GMA (21%), TEGDMA (14%) for FRC1; bis-GMA (21%), HEMA (14%) for FRC2; bis-GMA (3.5%), UDMA (21%), TEGDMA (10.5%) for FRC3, and bis-GMA (3.5%), UDMA (21%), HEMA (10.5%) for FRC4. Cytotoxicity test was performed on both human dental pulp stem cells and dermal fibroblasts. Viability was assessed by tetrazolium dye colorimetric assay. Subcutaneous implantation test was carried out on 40 male Wistar rats, randomly divided into 4 groups, according to the FRC tested. Each group received subcutaneous dorsal implants. After 30 days, intensity of the inflammatory reaction, tissue repair status, and presence of the capsule were the main criteria assessed. Both cell populations showed no signs of cytotoxicity following the FRC exposures. In terms of cytotoxicity, the best results were obtained by FRC3 followed by FRC2, FRC4, and FRC1. FRC3 showed also the mildest inflammatory reaction and this correlated both with the noncytotoxic behavior and the presence of a well-organized capsule. The composite biomaterials developed may constitute an optimized alternative of the similar materials used for the reconstruction of craniofacial bone defects. According to authors' studies, the authors conclude that FRC3 is the best formulation regarding the biological behavior.

  14. Feasibility study of prestressed natural fiber-reinforced polylactic acid (pla) composite materials

    Hinchcliffe, Sean A.

    The feasibility of manufacturing prestressed natural-fiber reinforced biopolymer composites is demonstrated in this work. The objective of this study was to illustrate that the specific mechanical properties of biopolymers can be enhanced by leveraging a combination of additive manufacturing (3D printing) and post-tensioning of continuous natural fiber reinforcement. Tensile and flexural PLA specimens were 3D-printed with and without post-tensioning ducts. The mechanical properties of reinforcing fibers jute and flax were characterized prior to post-tensioning. The effect of matrix cross-sectional geometry and post-tensioning on the specific mechanical properties of PLA were investigated using mechanical testing. Numerical and analytical models were developed to predict the experimental results, which confirm that 3D-printed matrices improve the specific mechanical properties of PLA composites and are further improved via initial fiber prestressing. The results suggest that both additive manufacturing and fiber prestressing represent viable new methods for improving the mechanical performance of natural fiber-reinforced polymeric composites.

  15. Material characterization of several resin systems for high temperature carbon fiber reinforced composites

    Yoon, Sung Ho; Oh, Jin Oh; Choi, Dong Hyun; Lee, Sang Woo


    Material characterization of several resin systems for high temperature carbon fiber reinforced composites was performed through a series of the tensile test, the dynamic mechanical analysis (DMA) test, and the strand test. The modified tensile specimens and the DMA specimens were used to evaluate the tensile and thermal analysis properties of resin systems. The strand specimens were used to evaluate the tensile properties and load transfer efficiencies of the specimens. Four types of resin systems were considered. One was a conventional resin system currently used for filament wound structures and other three were high temperature resin systems. According to the tensile and DMA test results, the tensile modulus decreases slightly and the tensile strength decreases rapidly until the temperature reaches glass transition temperature. The tensile modulus and tensile strength are almost negligible above glass transition temperature. The tensile modulus obtained from the tensile test is consistent with that from the DMA test at different temperatures. From the strand test results, considering, the load transfer efficiency is found to be around 87 to 90 % of the tensile strength of T800H-12K carbon fibers for all resin systems except the specimen with the Type 2. Finally we found that the Type 4 is the best candidate for high temperature resin system applicable to filament wound structures in the view of the glass transition temperature as well as the tensile properties.

  16. Application of radiation-crosslinked polytetrafluoroethylene to fiber-reinforced composite materials

    Oshima, Akihiro E-mail:; Udagawa, Akira; Morita, Yousuke


    Plain-woven carbon fiber-filled polytetrafluoroethylene (PTFE) composites were fabricated by radiation-crosslinking under selective conditions. High mechanical and frictional properties are found in the composite materials compared with crosslinked PTFE without fiber. The composite materials with optional shapes, which are laminated after electron beam (EB) crosslinking treatment of each mono-layer could also be fabricated. (author)

  17. Laser-Generated Lamb Waves Propagation in Multilayered Plates Composed of Viscoelastic Fiber-reinforced Composite Materials

    Sun, Hong-xiang; Zhang, Shu-yi; Yuan, Shou-qi; Guan, Yi-jun; Ge, Yong


    The propagation characteristics of laser-generated Lamb waves in multilayered fiber-reinforced composite plates with different fiber orientations and number of layers have been investigated quantitatively. Considering the viscoelasticity of the composite materials, we have set up finite element models for simulating the laser-generated Lamb waves in two types of the multilayered composite plates. In the first type, different fiber orientations are adopted. In the second one, different number of layers are considered. The results illustrate the occurrence of attenuation and dispersion, which is induced by the viscoelasticity and multilayer structure, respectively.

  18. Recycling solid residues recovered from glass fibre-reinforced composites – A review applied to wind turbine blade materials

    Beauson, Justine; Lilholt, Hans; Brøndsted, Povl


    to face large amount of future wind turbine (WT) blades coming to EoL. Among the EoL solutions available for WT blades, i.e. reuse, remanufacturing, recycling, incineration or disposal, this literature review focuses on recycling and particularly the recycling of shredded composite (SC) materials...... and recovered glass fibre (GF) into new polymer composite. WT blades are mainly made of glass fibre reinforced polymer (GFRP) using thermosetting resins. Shredding this material and recovering GF are possible recycling solutions for WT blade. Based on a detailed literature review, the formulations of new...

  19. Recovery of microfields in fiber-reinforced composite materials: Principles and limitations

    Ritchey, Andrew J.

    A detailed investigation of the limitations and errors induced by modeling a composite layer composed of straight carbon fibers embedded in an epoxy matrix as an homogenous layer with Cauchy effective moduli is performed. Specifically, the material system studied has IM7 carbon fibers arranged in a square array and bonded together with 8552 epoxy resin (IM7/8552). The finite element method is used to study the effect of free surfaces on the local elastic fields in 0°, 45° and 90° laminae, in which as many as 256 individual fibers are modeled. Through these analyses, it is shown that a micro-boundary layer, analogous to the macro-boundary layer observed in composite laminates, is developed at the microlevel. Additionally, [0/90]s and [90/0]s laminates are studied to investigate the joint action of the macro- and micro-boundary layers. Unless otherwise noted, fiber volume fractions of Vƒ=0.20 and Vƒ=0.65 are selected and the domains are subjected to uniform axial extension. Although this study is done for a highly idealized geometry (i.e. with a single material system and under a simple loading condition) the principles of periodicity, symmetry and antisymmetry used to efficiently perform a direct numerical simulation with a large number of fiber inclusions is general, and can be applied to more complicated geometries and boundary conditions. The purpose of the current work is to be the first step in a building block approach to understanding the interaction of multiple scales in fiber-reinforced composites through direct numerical simulations. The main part of the current manuscript focuses on the characterization of a micro-boundary layer that develops in fiber reinforced composite layers. This phenomena results from the changing constraints on the constituent phases as a result of discontinuities, such as free surfaces or ply interfaces. The effect is most pronounced in laminae that have a fiber termination intersecting a free surface, and appears to be

  20. Fracture Resistance of Endodontically Treated Teeth Restored with 2 Different Fiber-reinforced Composite and 2 Conventional Composite Resin Core Buildup Materials: An In Vitro Study.

    Eapen, Ashly Mary; Amirtharaj, L Vijay; Sanjeev, Kavitha; Mahalaxmi, Sekar


    The purpose of this in vitro study was to comparatively evaluate the fracture resistance of endodontically treated teeth restored with 2 fiber-reinforced composite resins and 2 conventional composite resin core buildup materials. Sixty noncarious unrestored human maxillary premolars were collected, endodontically treated (except group 1, negative control), and randomly divided into 5 groups (n = 10). Group 2 was the positive control. The remaining 40 prepared teeth were restored with various direct core buildup materials as follows: group 3 teeth were restored with dual-cure composite resin, group 4 with posterior composite resin, group 5 with fiber-reinforced composite resin, and group 6 with short fiber-reinforced composite resin. Fracture strength testing was performed using a universal testing machine. The results were statistically analyzed by 1-way analysis of variance and the post hoc Tukey test. Fracture patterns for each sample were also examined under a light microscope to determine the level of fractures. The mean fracture resistance values (in newtons) were obtained as group 1 > group 6 > group 4 > group 3 > group 5 > group 2. Group 6 showed the highest mean fracture resistance value, which was significantly higher than the other experimental groups, and all the fractures occurred at the level of enamel. Within the limitations of this study, a short fiber-reinforced composite can be used as a direct core buildup material that can effectively resist heavy occlusal forces against fracture and may reinforce the remaining tooth structure in endodontically treated teeth. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  1. Polymer matrix composite materials reinforced by Tb0.3Dy0.7Fe1.9 magnetostrictive particles

    L.A. Dobrzański


    Full Text Available The goal of this work was to describe manufacturing process of polymer matrix composite materials reinforced by Tb0.3Dy0.7Fe1.9 particles and to observe changes of physical properties (magnetic properties and magnetostriction of samples with randomly oriented magnetostrictive particles in epoxy matrix and with aligning these particles in the matrix during fabrication process.Design/methodology/approach: Polymer matrix composite materials reinforced by the Tb0.3Dy0.7Fe1.9 magnetostrictive particles fabricating method was developed during the investigations, making it possible to obtain materials with good physical properties. The influence of the concentration of the Td0.3Dy0.7Fe1.9 particles on magnetic and magnetostrictive properties was estimated. Metallographic examination of powder’s morphology as well as EDS and XRD analysis and observations the structure of composite materials were made.Findings: The influence of magnetic particle alignment is observed in the magnetic and magnetostriction responses. The magnetostrictive response improves when the magnetic particles are oriented in magnetic fields and reaches approximately 184 ppm for oriented composite materials with 25% volume fraction of Td0.3Dy0.7Fe1.9 particles.Practical implications: For potential applications in technological devices, such as sensors and actuators, it is desirable to form composite systems by combining magnetostrictive phases with matrix, in order to have giant magnetostrictive effect and, at the same time, to reduce disadvantages of monolithic material.Originality/value: The originality of this work is based on manufacturing process, especially of applying magnetic alignment for ordering Td0.3Dy0.7Fe1.9 particles during polymerization of epoxy matrix.

  2. Failure Criteria for Reinforced Materials

    Rathkjen, Arne

    Failure of materials is often characterized as ductile yielding, brittle fracture, creep rupture, etc., and different criteria given in terms of different parameters have been used to describe different types of failure. Only criteria expressing failure in terms of stress are considered in what...... place until the matrix, the continuous component of the composite, fails. When an isotropic matrix is reinforced as described above, the result is an anisotropic composite material. Even if the material is anisotropic, it usually exhibits a rather high degree of symmetry and such symmetries place...... certain restrictions on the form of the failure criteria for anisotropic materials. In section 2, some failure criteria for homogenous materials are reviewed. Both isotropic and anisotropic materials are described, and in particular the constraints imposed on the criteria from the symmetries orthotropy...

  3. Machining of fiber reinforced composites

    Komanduri, Ranga; Zhang, Bi; Vissa, Chandra M.

    Factors involved in machining of fiber-reinforced composites are reviewed. Consideration is given to properties of composites reinforced with boron filaments, glass fibers, aramid fibers, carbon fibers, and silicon carbide fibers and to polymer (organic) matrix composites, metal matrix composites, and ceramic matrix composites, as well as to the processes used in conventional machining of boron-titanium composites and of composites reinforced by each of these fibers. Particular attention is given to the methods of nonconventional machining, such as laser machining, water jet cutting, electrical discharge machining, and ultrasonic assisted machining. Also discussed are safety precautions which must be taken during machining of fiber-containing composites.

  4. Machining fiber-reinforced composites

    Komanduri, Ranga


    Compared to high tool wear and high costs of tooling of fiber-reinforced composites (FRCs), noncontact material-removal processes offer attractive alternative. Noncontact machining methods can also minimize dust, noise, and extensive plastic deformation and consequent heat generation associated with conventional machining of FRCs, espacially those with an epoxy matrix. The paper describes the principles involved in and the details of machining of FRCs by laser machining, water jet-cutting and abrasive water jet-cutting, and electrical discharge machining of composites, as well as the limitations of each method.

  5. Long Term Behavior of Composite Material Polyester-Wood Reinforced Glass Fiber

    E.T. Olodo


    Full Text Available If the industry generally considers composite materials as potentially interesting, the lack of durability makes their often limited employment. Indeed, the design of composite structures often requires taking account of the long-term behaviour under various types of complex solicitations. This study is based on the development of a methodology for modeling the long term behavior under constant load for multilayer composite structures subjected to complex solicitations. This study is on the evaluation of the long-term behaviour of tri-layers glass/polyester-wood composite material. The objective is the evaluation of the long term strength of this material by the Goldenblat-Kopnov criterion. The studied model is an orthotropic tri layer plate of sandwich type with upper and lower flanges (skins are in composite material glass/polyester KACT-B and the intermediate layer (soul is pine wood. The character of loading of the plate is reflected in the model by the functions &sigmaik(&xi, &sigmamn(&xi which can be of different natures. For example, to load in the long term by constant constraints in time (the weight own element for example, we will have: &sigmaik = const &sigmamn = const. The results of the calculations show that, for this type of material, the conditions of strength to the dangerous points of the plate are met.

  6. A multi-purpose optical fibre sensor design for fibre reinforced composite materials

    Fernando, G. F.; Liu, T.; Crosby, P.; Doyle, C.; Martin, A.; Brooks, D.; Ralph, B.; Badcock, R.


    This paper reports on the evaluation of a multi-functional extrinsic Fabry - Pérot optical fibre-based sensor design. The sensor was constructed using multimode and single mode optical fibres and a precision bore capillary tube. Fusion joints were used to secure the optical fibres into the capillary tube. The separation between the cleaved end-faces of the optical fibres defined the cavity length for the Fabry - Pérot sensor and the distance between the fusion joints defined the gauge length for this strain and temperature sensor. The sensor design was modified to: (i) monitor the progress of cure in an epoxy/amine resin system; (ii) detect the ingress of moisture in a cured epoxy/amine resin system; (iii) monitor the vibration characteristics of a pre- and post-impact damaged carbon fibre reinforced epoxy panel; and (iv) discriminate between strain and temperature measurements. The feasibility of using this type of sensor for cure monitoring, strain, temperature, residual stress measurements and damage detection in advanced fibre reinforced composites is demonstrated.

  7. Self-sealing of thermal fatigue and mechanical damage in fiber-reinforced composite materials

    Moll, Jericho L.

    Fiber reinforced composite tanks provide a promising method of storage for liquid oxygen and hydrogen for aerospace applications. The inherent thermal fatigue of these vessels leads to the formation of microcracks, which allow gas phase leakage across the tank walls. In this dissertation, self-healing functionality is imparted to a structural composite to effectively seal microcracks induced by both mechanical and thermal loading cycles. Two different microencapsulated healing chemistries are investigated in woven glass fiber/epoxy and uni-weave carbon fiber/epoxy composites. Self-healing of mechanically induced damage was first studied in a room temperature cured plain weave E-glass/epoxy composite with encapsulated dicyclopentadiene (DCPD) monomer and wax protected Grubbs' catalyst healing components. A controlled amount of microcracking was introduced through cyclic indentation of opposing surfaces of the composite. The resulting damage zone was proportional to the indentation load. Healing was assessed through the use of a pressure cell apparatus to detect nitrogen flow through the thickness direction of the damaged composite. Successful healing resulted in a perfect seal, with no measurable gas flow. The effect of DCPD microcapsule size (51 microm and 18 microm) and concentration (0--12.2 wt%) on the self-sealing ability was investigated. Composite specimens with 6.5 wt% 51 microm capsules sealed 67% of the time, compared to 13% for the control panels without healing components. A thermally stable, dual microcapsule healing chemistry comprised of silanol terminated poly(dimethyl siloxane) plus a crosslinking agent and a tin catalyst was employed to allow higher composite processing temperatures. The microcapsules were incorporated into a satin weave E-glass fiber/epoxy composite processed at 120°C to yield a glass transition temperature of 127°C. Self-sealing ability after mechanical damage was assessed for different microcapsule sizees (25 microm and 42

  8. Strain Sensing Based on Multiscale Composite Materials Reinforced with Graphene Nanoplatelets.

    Moriche, Rocío; Prolongo, Silvia G; Sánchez, María; Jiménez-Suárez, Alberto; Campo, Mónica; Ureña, Alejandro


    The electrical response of NH2-functionalized graphene nanoplatelets composite materials under strain was studied. Two different manufacturing methods are proposed to create the electrical network in this work: (a) the incorporation of the nanoplatelets into the epoxy matrix and (b) the coating of the glass fabric with a sizing filled with the same nanoplatelets. Both types of multiscale composite materials, with an in-plane electrical conductivity of ~10(-3) S/m, showed an exponential growth of the electrical resistance as the strain increases due to distancing between adjacent functionalized graphene nanoplatelets and contact loss between overlying ones. The sensitivity of the materials analyzed during this research, using the described procedures, has been shown to be higher than commercially available strain gauges. The proposed procedures for self-sensing of the structural composite material would facilitate the structural health monitoring of components in difficult to access emplacements such as offshore wind power farms. Although the sensitivity of the multiscale composite materials was considerably higher than the sensitivity of metallic foils used as strain gauges, the value reached with NH2 functionalized graphene nanoplatelets coated fabrics was nearly an order of magnitude superior. This result elucidated their potential to be used as smart fabrics to monitor human movements such as bending of fingers or knees. By using the proposed method, the smart fabric could immediately detect the bending and recover instantly. This fact permits precise monitoring of the time of bending as well as the degree of bending.

  9. Damage Precursor Investigation of Fiber-Reinforced Composite Materials Under Fatigue Loads


    measures of damage that act as damage precursors also exist, such as electric resistance (Wang et al., 1998; Irving and 4 Thiagarajan, 1998; Weber... Irving , P. E.; Thiagarajan, C. Fatigue Damage Characterization in Carbon Fibre Composite Materials Using an Electrical Potential Technique. Smart...30 NO. OF COPIES ORGANIZATION 1 DEFENSE TECHNICAL (PDF) INFORMATION CTR DTIC OCA 2 DIRECTOR (PDFS) US ARMY RESEARCH LAB

  10. GRC: Composite material from an inorganic matrix reinforced with AR glass fibres

    Comino Almenara, P. I.


    Full Text Available This article describes the historical background of Cem-FIL. Alkali Resistant Glass Fibre, as well as the composite characteristics of the element they generate: GRC. The most important advantages and properties of this type of Composite Material are also detailed.

    En este artículo se detallan cuáles son las bases históricas de las Fibras de Vidrio Álcali-Resistentes Cem-FIL así como las características del elemento compuesto que ellas generan: GRC. En este documento también se pueden encontrar indicaciones sobre las principales ventajas y propiedades de este tipo de Material Compuesto.

  11. Lignocellulosic fiber reinforced rubber composites

    Jacob John, Maya


    Full Text Available stream_source_info John_d1_2009.pdf.txt stream_content_type text/plain stream_size 43167 Content-Encoding UTF-8 stream_name John_d1_2009.pdf.txt Content-Type text/plain; charset=UTF-8 -252- CHAPTER 10: LIGNOCELLULOSIC... FIBER REINFORCED RUBBER COMPOSITES Maya JACOB JOHN1 Rajesh D. ANANDJIWALA2 (1)CSIR Materials Science and Manufacturing, Fibres and Textiles Competence Area, P.O. Box 1124, Port Elizabeth 6000, South Africa, E-mail: (2) Department...

  12. Compressive strength of fiber reinforced composite materials. [composed of boron and epoxy

    Davis, J. G., Jr.


    Results of an experimental and analytical investigation of the compressive strength of unidirectional boron-epoxy composite material are presented. Observation of fiber coordinates in a boron-epoxy composite indicates that the fibers contain initial curvature. Combined axial compression and torsion tests were conducted on boron-epoxy tubes, and it was shown that the shear modulus is a function of axial compressive stress. An analytical model which includes initial curvature in the fibers and permits an estimate of the effect of curvature on compressive strength is proposed. Two modes of failure which may result from the application of axial compressive stress are analyzed, delamination and shear instability. Based on tests and analysis, failure of boron-epoxy under axial compressive load is due to shear instability.

  13. Contributions in the Preparation and Processing of Composite Material Type Silumin 3 - Reinforced Matrix with S235JR Steel Mesh

    Remus Belu-Nica


    Full Text Available In the paper are presented concrete data on developing technological batches of metal composite material (MCM type Silumin 3-reinforced matrix with steel mesh S235JR, with the indicating of the parameter and of the distinct stages of work. The samples from prepared batches were cut along and across by water jet abrasive process and were subjected to a destructive testing program and microstructural examination, obtaining results in concordance with the desired quality. The abrasive material used for cut was GMA granite with the average mesh of 80, the particle size ranging between 150-300 µm, density 2300 kg/m3 and melting point 1240°C.

  14. Studies of Matrix/Fiber Reinforced Composite Materials for the High Speed Research (HSR) Program

    Orwoll, Robert A.


    The research on the curing mechanism of the phenylethynyl terminated imide matrix resins was the primary focus of this research. The ability to process high performance polymers into useful adhesives and high quality composites has been significantly advanced by synthetic techniques in which oligomers terminated with reactive groups cure or crosslink at elevated temperature after the article has been fabricated. The research used a variety of analytical techniques. Many stable products were isolated, and attempts at identification were made. This research was intended to provide fundamental insight into the molecular structure of these new engineering materials.

  15. The Comparison of Shear Bond Strength Between Fibre Reinforced Composite Posts with Three Different Composite Core Materials – An In vitro Study

    Anche, Sampath; Kakarla, Pranitha; Kadiyala, Krishna Kishore; Sreedevi, B.; Chiramana, Sandeep; Dev J., Ravi Rakesh; Manne, Sanjay Dutt; G., Deepthi


    Aim: The aim of this study is to compare the shear bond strength between fiber reinforced composite post with three different composite core materials. Materials and Methods: The materials used for the study were: 30 maxillary central incisors, pre fabricated fiber reinforced composite post (postec plus posts), Multi-core heavy body, Ti-core, Fluoro-core, Etchant gel, Silane coupling agent, Dentin bonding agent, Standardized gutta percha points, Rely-X dual cure composite resin. A total of 30 human maxillary central incisor were selected for this study. They were divided into three groups of 10 specimens each namely A, B and C. Results: The results obtained were analyzed by using one way analysis (ANOVA) and Tukey Honestly Significant Difference and they showed highest mean shear bond strength for group C when compared with group A and group B. There is no significant difference in the shear bond strength values between group A and group B. Conclusion: The teeth restored with multicore HB showed highest shear bond strength. The teeth restored with Fluoro core showed lowest shear bond strength. No statistically significant difference exists between the shear bond strength values between Ti-core and Fluoro-core. PMID:24596784

  16. Seismic Material Properties of Reinforced Concrete and Steel Casing Composite Concrete in Elevated Pile-Group Foundation

    Zhou Mi


    Full Text Available The paper focuses on the material mechanics properties of reinforced concrete and steel casing composite concrete under pseudo-static loads and their application in structure. Although elevated pile-group foundation is widely used in bridge, port and ocean engineering, the seismic performance of this type of foundation still need further study. Four scale-specimens of the elevated pile-group foundation were manufactured by these two kinds of concrete and seismic performance characteristic of each specimen were compared. Meanwhile, the special soil box was designed and built to consider soil-pile-superstructure interaction. According to the test result, the peak strength of strengthening specimens is about 1.77 times of the others and the ultimate displacement is 1.66 times of the RC specimens. Additionally, the dissipated hysteric energy capability of strengthening specimens is more than 2.15 times of the others as the equivalent viscous damping ratio is reduced by 50%. The pinching effect of first two specimens is more obvious than latter two specimens and the hysteretic loops of reinforced specimens are more plumpness. The pseudo-static tests also provided the data to quantitatively assessment the positive effect of steel casing composite concrete in aseismatic design of bridge.

  17. The Comparison of Shear Bond Strength Between Fibre Reinforced Composite Posts with Three Different Composite Core Materials - An In vitro Study.

    Anche, Sampath; Kakarla, Pranitha; Kadiyala, Krishna Kishore; Sreedevi, B; Chiramana, Sandeep; Dev J, Ravi Rakesh; Manne, Sanjay Dutt; G, Deepthi


    The aim of this study is to compare the shear bond strength between fiber reinforced composite post with three different composite core materials. The materials used for the study were: 30 maxillary central incisors, pre fabricated fiber reinforced composite post (postec plus posts), Multi-core heavy body, Ti-core, Fluoro-core, Etchant gel, Silane coupling agent, Dentin bonding agent, Standardized gutta percha points, Rely-X dual cure composite resin. A total of 30 human maxillary central incisor were selected for this study. They were divided into three groups of 10 specimens each namely A, B and C. The results obtained were analyzed by using one way analysis (ANOVA) and Tukey Honestly Significant Difference and they showed highest mean shear bond strength for group C when compared with group A and group B. There is no significant difference in the shear bond strength values between group A and group B. The teeth restored with multicore HB showed highest shear bond strength. The teeth restored with Fluoro core showed lowest shear bond strength. No statistically significant difference exists between the shear bond strength values between Ti-core and Fluoro-core.

  18. Carbon Nanotubes Reinforced Composites for Biomedical Applications

    Wei Wang; Yuhe Zhu; Susan Liao; Jiajia Li


    This review paper reported carbon nanotubes reinforced composites for biomedical applications. Several studies have found enhancement in the mechanical properties of CNTs-based reinforced composites by the addition of CNTs. CNTs reinforced composites have been intensively investigated for many aspects of life, especially being made for biomedical applications. The review introduced fabrication of CNTs reinforced composites (CNTs reinforced metal matrix composites, CNTs reinforced polymer matr...

  19. Inorganic nanotubes reinforced polyvinylidene fluoride composites as low-cost electromagnetic interference shielding materials

    Sankaranarayanan Venkataraman


    Full Text Available Abstract Novel polymer nanocomposites comprising of MnO2 nanotubes (MNTs, functionalized multiwalled carbon nanotubes (f-MWCNTs, and polyvinylidene fluoride (PVDF were synthesized. Homogeneous distribution of f-MWCNTs and MNTs in PVDF matrix were confirmed by field emission scanning electron microscopy. Electrical conductivity measurements were performed on these polymer composites using four probe technique. The addition of 2 wt.% of MNTs (2 wt.%, f-MWCNTs to PVDF matrix results in an increase in the electrical conductivity from 10-16S/m to 4.5 × 10-5S/m (3.2 × 10-1S/m. Electromagnetic interference shielding effectiveness (EMI SE was measured with vector network analyzer using waveguide sample holder in X-band frequency range. EMI SE of approximately 20 dB has been obtained with the addition of 5 wt.% MNTs-1 wt.% f-MWCNTs to PVDF in comparison with EMI SE of approximately 18 dB for 7 wt.% of f-MWCNTs indicating the potential use of the present MNT/f-MWCNT/PVDF composite as low-cost EMI shielding materials in X-band region.

  20. An experimental study on the influence of composite materials used to reinforce masonry ring beams

    Sisti, Romina; Corradi, Marco; Borri, Antonio


    For historic masonry constructions the out-of-plane wall behavior is critical to seismic performance. Because the main cause of out-of-plane collapses is the wall-to-wall level of connection, the application of a reinforced concrete (RC) ring beam at the eaves level of historic masonry buildings is an effective method to prevent an out-of-plane mechanism of a wall panel. However this effective reinforcing method presents some drawbacks. In order to address this, this paper describes the probl...

  1. Advanced X-Ray Inspection of Reinforced Carbon Composite Materials on the Orbiter Leading Edge Structural Subsystem (LESS)

    Hernandez, Jose M.; Berry, Robert F.; Osborn, Robin; Bueno, Clifford; Osterlitz, Mark; Mills, Richard; Morris, Philip; Phalen, Robert; McNab, Jim; Thibodeaux, Tahanie; Thompson, Kyle


    The post return-to-flight (RTF) inspection methodology for the Orbiter Leading Edge Structural Subsystem (LESS) is currently being defined. Numerous NDT modalities and techniques are being explored to perform the flight-to-flight inspections of the reinforced carbon/carbon (RCC) composite material for impact damage, general loss of mass in the bulk layers, or other anomalous conditions that would pose risk to safe return upon re-entry. It is possible to have an impact upon ascent that is not visually observable on the surface, yet causes internal damage. Radiographic testing may be a useful NDT technique for such occurrences. The authors have performed radiographic tests on full-sized mock samples of LESS hardware with embedded image quality phantoms. Digitized radiographic film, computed radiography and flat panel digital real-time radiography was acquired using a GE Eresco 200 x-ray tube, and Se-75 and Yb-169 radioisotopes.

  2. Opportunities and challenges for textile reinforced composites

    Pastore, Christopher M.


    For several decades researchers have been interested in textile processes for the production of composite reinforcement. These technologies have offered several promises: reduced fabrication costs, 3-D multiaxial reinforcement, and damage tolerance. Despite these advantages, textile composites have not reached the level of implementation of laminated composites. In this paper, the opportunities provided by textile reinforced composites and the challenges that limit their implementation will be discussed in detail. Textile composites refer to a family of processes: weaving, braiding, knitting, and hybrids thereof. The various families of textiles will be defined and the basics of fabric formation for each family will be detailed. In particular, the strengths and weaknesses of each manufacturing technique will be addressed to provide a view of the applicability of each technology. This will include some guidance on shape formation capability, property ranges, size limitations, and estimates of cost to produce. Potential applications for these materials will be presented. Among the limitations on the application of textile reinforced composites is the lack of adequate modeling capabilities for these materials. Textile composites have rather large unit cell structures and are highly inhomogeneous throughout their volumes. These features provide benefits in manufacturing, but require novel modeling techniques to correctly understand the mechanical behavior. A review of analytical techniques applied to textile composites will be presented along with a discussion of the benefits and weaknesses of each of these methods. The enabling technologies needed to further the implementation of textile composites in structural applications will be discussed.

  3. Carbon Nanotubes Reinforced Composites for Biomedical Applications

    Wei Wang


    Full Text Available This review paper reported carbon nanotubes reinforced composites for biomedical applications. Several studies have found enhancement in the mechanical properties of CNTs-based reinforced composites by the addition of CNTs. CNTs reinforced composites have been intensively investigated for many aspects of life, especially being made for biomedical applications. The review introduced fabrication of CNTs reinforced composites (CNTs reinforced metal matrix composites, CNTs reinforced polymer matrix composites, and CNTs reinforced ceramic matrix composites, their mechanical properties, cell experiments in vitro, and biocompatibility tests in vivo.

  4. Carbon nanotubes reinforced composites for biomedical applications.

    Wang, Wei; Zhu, Yuhe; Liao, Susan; Li, Jiajia


    This review paper reported carbon nanotubes reinforced composites for biomedical applications. Several studies have found enhancement in the mechanical properties of CNTs-based reinforced composites by the addition of CNTs. CNTs reinforced composites have been intensively investigated for many aspects of life, especially being made for biomedical applications. The review introduced fabrication of CNTs reinforced composites (CNTs reinforced metal matrix composites, CNTs reinforced polymer matrix composites, and CNTs reinforced ceramic matrix composites), their mechanical properties, cell experiments in vitro, and biocompatibility tests in vivo.

  5. Development of an Iron-Based Hardfacing Material Reinforced with Fe-(TiW)C Composite Powder

    Correa, E. O.; Alcantara, N. G.; Tecco, D. G.; Kumar, R. V.


    The objective of this work is to investigate the correlation of microstructure with wear resistance in a hardfacing material reinforced with Fe-(TiW)C composite powder particles. This material was designed for cladding components subjected to highly abrasive conditions and was deposited on a low-carbon steel substrate by open arc welding. The theoretical and experimental work undertaken includes solidification study, microstructural characterization, and abrasive wear testing. Microstructural analysis of the hardfaced top layer of the alloy showed the presence of TiWC carbide particles and TiNbC carbides randomly distributed in a eutectic mixture matrix γ/M7C3 containing primary austenite dendrites. Microstructural examinations also showed that hard and fine spherulitic carbides, in which a Ti-rich MC carbide core was encircled by MC carbide enriched with Nb and W, were homogeneously distributed in the matrix. The energy-dispersive spectroscopy (EDS) mapping of spherulitic carbides showed that the any added Nb replaced a significant part of W in the Fe-(TiW)C powder, and W preferentially partitioned into other carbides and matrix during solidification. Abrasion test results showed that the preceding carbides improve the wear resistance of the hardfacing material in comparison with conventional Fe-Cr-C and Fe-Cr-C-Nb alloys, especially under high stress conditions.

  6. Effect of Sea Water on Drilling Processes of Glass Fibre Reinforced Epoxy Composite Materials to Analysis of Delamination Factor and Thrust Force

    Patil Deogonda B


    Full Text Available Fiber reinforced polymer composites have gained substantial attention as engineering structural materials in automotive, marine and aircraft industry as well as in civil engineering applications. This is due to their outstanding mechanical properties, impact resistance, high durability and flexibility in design capabilities and light weight The present work describes the development and mechanical characterization of new polymer composites consisting of glass fiber reinforcement, epoxy resin and filler materials such as TiO2 and ZnS. The newly developed composites are characterized for their mechanical properties. The tests result have shown that higher the filler material volume percentage greater the strength for both TiO2 and ZnS filled glass epoxy composites, ZnS filled composite show more sustaining values than TiO2. The present work also describes the machining (drilling of GFRP composites with the help of Step drill of three sets, with three different speeds. The work has been carried out by immersion of GFRP composites in sea water for 8hrs, 16hrs and 24hrs duration and performed drilling operation. Results revealed that 8-4 mm step drill showed better machining characteristic than the other two 12-8mm and 10-6 mm step drills. GFRP composite, with ZnS filler material soaked in sea water for 16hrs duration had better machining capability. The ZnS Filled GFRP composites had better performance than TiO2 filled GFRP Composites.

  7. Size-dependent reinforcement of composite rubbers

    Mermet-Guyennet, M.R.B.; de Castro, J.G.; Varol, H.S.; Habibi, M.; Hosseinkhani, B.; Martzel, N.; Sprik, R.; Denn, M.M.; Zaccone, A.; Parekh, S.H.; Bonn, D.


    Particulate fillers are often used to enhance the properties of soft materials; polymer composites often contain nanometer-sized particles to improve reinforcement, for example. The rationale for using nanometer-sized particles remains unclear, however, and classical micromechanical models cannot ac




    Full Text Available This paper discusses about the Natural Fiber Reinforced Composite Materials contribution as bone implants. Biomaterial science is an interdisciplinary field that represents one of the most sophisticated trends in worldwide medical practice. In the last decades, researchers have developed new materials to improve the quality of human life. Owing to the frequent occurrence of bone fractures, it is important to develop a plate material for fixation on the fractured bone. These plate materials have to be lightweight, allow stiffness, and be biocompatible with humans. Drilling is the most frequently employed operation of secondary machining for fiber-reinforced materials, owing to the need for joining fractured bone by means of plate material in the field of orthopedics. An effort to utilize theadvantages offered by renewable resources for the development of biocomposite materials based on biopolymers and natural fibers has been made through fabrication of Natural fiber powdered material (Sisal (Agave sisalana, Banana (Musa sepientum, and Roselle (Hibiscus sabdariffa reinforced polymer composite plate material by using bio epoxy resin Grade 3554A and Hardner 3554B. Instead of orthopedics alloys such as Titanium, Cobalt chrome, Stainless steel, and Zirconium, this plate material can be used for internal fixationand aso external fixation on human body for fractured bone. The present work focuses on the prediction of thrust force and torque of the natural fiber reinforced polymer composite materials, and the values, compared with the Regression model and the Scheme of Delamination factor / zone using machine vision system, also discussed with the help of Scanning Electron Microscope [SEM].

  9. Thickness optimization of fiber reinforced laminated composites using the discrete material optimization method

    Sørensen, Søren Nørgaard; Lund, Erik


    This work concerns a novel large-scale multi-material topology optimization method for simultaneous determination of the optimum variable integer thickness and fiber orientation throughout laminate structures with fixed outer geometries while adhering to certain manufacturing constraints. The con......This work concerns a novel large-scale multi-material topology optimization method for simultaneous determination of the optimum variable integer thickness and fiber orientation throughout laminate structures with fixed outer geometries while adhering to certain manufacturing constraints....... The conceptual combinatorial/integer problem is relaxed to a continuous problem and solved on basis of the so-called Discrete Material Optimization method, explicitly including the manufacturing constraints as linear constraints....

  10. The effect of fibre content, fibre size and alkali treatment to Charpy impact resistance of Oil Palm fibre reinforced composite material

    Fitri, Muhamad; Mahzan, Shahruddin


    In this research, the effect of fibre content, fibre size and alkali treatment to the impact resistance of the composite material have been investigated, The composite material employs oil palm fibre as the reinforcement material whereas the matrix used for the composite materials are polypropylene. The Oil Palm fibres are prepared for two conditions: alkali treated fibres and untreated fibres. The fibre sizes are varied in three sizes: 5mm, 7mm and 10mm. During the composite material preparation, the fibre contents also have been varied into 3 different percentages: 5%, 7% and 10%. The statistical approach is used to optimise the variation of specimen determined by using Taguchi method. The results were analyzed also by the Taguchi method and shows that the Oil Palm fibre content is significantly affect the impact resistance of the polymer matrix composite. However, the fibre size is moderately affecting the impact resistance, whereas the fibre treatment is insignificant to the impact resistance of the oil palm fibre reinforced polymer matrix composite.

  11. Kevlar reinforced neoprene composites

    Penn, B. G.; Daniels, J. G.; White, W. T.; Thompson, L. M.; Clemons, L. M.


    Kevlar/neoprene composites were prepared by two techniques. One method involved the fabrication of a composite from a rubber prepreg prepared by coating Kevlar with viscous neoprene solution and then allowing the solvent to evaporate (solution impregnation technique). The second method involved heating a stack of Kevlar/neoprene sheets at a temperature sufficient to cause polymer flow (melt flow technique). There was no significant difference in the breaking strength and percent elongation for samples obtained by the two methods; however the shear strength obtained for samples fabricated by the solution impregnation technique (275 psi) was significantly higher than that found for the melt flow fabricated samples (110 psi).

  12. Drastic Improvements in Bonding of Fiber Reinforced Multifunctional Composites Project

    National Aeronautics and Space Administration — Achievement of a dramatic increase in the bond strength in the adhesive and composite/adhesive interfaces of existing fiber reinforced composite material joints and...

  13. Drastic Improvements in Bonding of Fiber Reinforced Multifunctional Composites Project

    National Aeronautics and Space Administration — Achievement of a dramatic increase in the bond strength in the composite/adhesive interfaces of existing fiber reinforced polymer (FRP) composite material joints and...

  14. Effects of different acids and etching times on the bond strength of glass fiber-reinforced composite root canal posts to composite core material.

    Güler, Ahmet Umut; Kurt, Murat; Duran, Ibrahim; Uludamar, Altay; Inan, Ozgur


    To investigate the effects of different acids and etching times on the bond strength of glass fiber-reinforced composite (FRC) posts to composite core material. Twenty-six FRC posts (FRC Postec Plus) were randomly divided into 13 groups (each n = 2). One group received no surface treatment (control). The posts in the other groups were acid etched with 35% phosphoric acid and 5% and 9.6% hydrofluoric acid gel for four different etching times (30, 60, 120, and 180 seconds). A cylindric polytetrafluoroethylene mold was placed around the treated posts and filled with dual-cure composite core material (MultiCore Flow). All samples were light cured for 60 seconds. After 24 hours of water storage, the specimens were sectioned perpendicularly to the bonded interface under water cooling to obtain 2-mm post-and-core specimens. Eight specimens were made from each group. Push-out tests were performed at a crosshead speed of 0.5 mm/min using a universal testing machine. Data were analyzed by one-way ANOVA followed by the Tukey honestly significant difference test (alpha = .05). The lowest bond strength was observed in the control group (12.51 megapascal [MPa]). No statistical significant difference was observed among group H5-120 (20.31 MPa), group H9-120 (20.55 MPa), or group P-180 (20.57 MPa) (P > .05). These groups demonstrated the highest bond strength values (P strength when compared with the control group. Acid-etching with 5% hydrofluoric acid and 9.6% hydrofluoric acid for 2 minutes and with 35% phosphoric acid for 3 minutes (groups H5-120, H9-120, and P-180, respectively) demonstrated the highest bond strength values between the FRC post and composite core material. Although the bond strength was increased by prolonged acid etching, the microstructure of the FRC posts might have been damaged.

  15. Provisional anterior tooth replacement using nonimpregnated fiber and fiber-reinforced composite resin materials: a clinical report.

    Chan, Daniel C N; Giannini, Marcelo; De Goes, Mario Fernando


    The loss of anterior teeth is often a serious esthetic concern. While conventional fixed partial dentures and implant-supported restorations may be the treatments of choice, nonimpregnated fibers (NFs) and fiber-reinforced composite (FRC) resins offer a conservative alternative for improving esthetics. This article describes 2 clinical situations in which NF glass ribbon and FRC were successfully used to provisionally restore anterior edentulous areas in an esthetic, functional, and timely manner.

  16. Improvement of Strength Characteristics of Aerospace Fiber Reinforced Composite Materials using Atmospheric Pressure Plasma-Graft Polymerization Treatment

    Aoi, Tatsuji; Kuroki, Tomoyuki; Tahara, Mitsuru; Okubo, Masaaki

    The atmospheric pressure nonthermal plasma-graft polymerization treatment is applied for the surface modification of the organic fibers in order to enhance the strength of the aerospace structural composite material consisting of the laminated textiles. The influence of the treatment on the composite materials' strength properties is examined. As a result, the plasma-graft polymerization surface treatment is effective for the compression and bend of the composite materials. Because the interfacial bonding between each fiber and matrix resin is strengthened by the treatment, the strengths of the composite materials are increased.

  17. Formability of tufted 3-dimensional composite reinforcement

    Liu, Ling Shan; Wang, Peng; Legrand, Xavier; Soulat, Damien


    In the aerospace industry, more and more complex preform for composite parts are needed. Traditionally, laminated reinforcement is largely used as the method. The development of tufting technology has now advanced to a stage whereby it can be employed to produce the 3D textile composite reinforcements. Because the tufting technology is user-friendly, in this study, the tufting parameters (tufting density, tufting length, tufting yarn orientations…) are varied, in order to improve the understanding of formability of the tufted 3D fabric during manufacturing, in particular the influence of the tufting yarns, the present work is performed to analyse the preforming behaviours of tufted 3D reinforcement in the hemispherical stamping process. The preforming behaviours are also compared with the ones of the multilayered forming. Interply sliding and winkling phenomenon during forming are fully influenced by tufting yarns on the material draw-in, by the orientations of tufting yarn, …

  18. Reinforcement of Conducting Silver-based Materials

    Heike JUNG


    Full Text Available Silver is a well-known material in the field of contact materials because of its high electrical and thermal conductivity. However, due to its bad mechanical and switching properties, silver alloys or reinforcements of the ductile silver matrix are required. Different reinforcements, e. g. tungsten, tungsten carbide, nickel, cadmium oxide or tin oxide, are used in different sectors of switches. To reach an optimal distribution of these reinforcements, various manufacturing techniques (e. g. powder blending, preform infiltration, wet-chemical methods, internal oxidation are being used for the production of these contact materials. Each of these manufacturing routes offers different advantages and disadvantages. The mechanical alloying process displays a successful and efficient method to produce particle-reinforced metal-matrix composite powders. This contribution presents the obtained fine disperse microstructure of tungsten-particle-reinforced silver composite powders produced by the mechanical alloying process and displays this technique as possible route to provide feedstock powders for subsequent consolidation processes. DOI:

  19. Reinforcement of Conducting Silver-based Materials

    Heike JUNG


    Full Text Available Silver is a well-known material in the field of contact materials because of its high electrical and thermal conductivity. However, due to its bad mechanical and switching properties, silver alloys or reinforcements of the ductile silver matrix are required. Different reinforcements, e. g. tungsten, tungsten carbide, nickel, cadmium oxide or tin oxide, are used in different sectors of switches. To reach an optimal distribution of these reinforcements, various manufacturing techniques (e. g. powder blending, preform infiltration, wet-chemical methods, internal oxidation are being used for the production of these contact materials. Each of these manufacturing routes offers different advantages and disadvantages. The mechanical alloying process displays a successful and efficient method to produce particle-reinforced metal-matrix composite powders. This contribution presents the obtained fine disperse microstructure of tungsten-particle-reinforced silver composite powders produced by the mechanical alloying process and displays this technique as possible route to provide feedstock powders for subsequent consolidation processes. DOI:

  20. Fiber reinforced polymer composites for bridge structures

    Alexandra CANTORIU


    Full Text Available Rapid advances in construction materials technology have led to the emergence of new materials with special properties, aiming at safety, economy and functionality of bridges structures. A class of structural materials which was originally developed many years ago, but recently caught the attention of engineers involved in the construction of bridges is fiber reinforced polymer composites. This paper provides an overview of fiber reinforced polymer composites used in bridge structures including types, properties, applications and future trends. The results of this study have revealed that this class of materials presents outstanding properties such as high specific strength, high fatigue and environmental resistance, lightweight, stiffness, magnetic transparency, highly cost-effective, and quick assembly, but in the same time high initial costs, lack of data on long-term field performance, low fire resistance. Fiber reinforced polymer composites were widely used in construction of different bridge structures such as: deck and tower, I-beams, tendons, cable stands and proved to be materials for future in this field.

  1. Effects of wheat starch on erosive wear of E-glass fibre reinforced epoxy resin composite materials

    Srivastava, V.K. [Department of Mechanical Engineering, Institute of Technology, Banaras Hindu University, Varanasi 221005 (India)]. E-mail:


    Erosive wear tests were carried out to study the effects of particle, impingement angle and particle velocity on the solid particle erosion behaviour of E-glass fibre reinforced epoxy resin (GFRP) composites. The erosive wear of wheat flour powder filled composites is evaluated at different impingement angles from 30 deg. to 90 deg. and at three different velocities of 24, 35 and 52 m s{sup -1}. The erodent used is silica sand with the size range 150-250 {mu}m of irregular shapes. The result shows erosive wear rates of GFRP composite with 2 g wheat flour, as filler is the lowest. This restricts fiber-matrix debonding. Pure glass epoxy without any filler shows the highest erosion rate due to weak bonding strength. The morphologies of eroded surface were examined by the scanning electron microscope.

  2. Composite material

    Hutchens, Stacy A.; Woodward, Jonathan; Evans, Barbara R.; O'Neill, Hugh M.


    A composite biocompatible hydrogel material includes a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa. A calcium comprising salt is disposed in at least some of the pores. The porous polymer matrix can comprise cellulose, including bacterial cellulose. The composite can be used as a bone graft material. A method of tissue repair within the body of animals includes the steps of providing a composite biocompatible hydrogel material including a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa, and inserting the hydrogel material into cartilage or bone tissue of an animal, wherein the hydrogel material supports cell colonization in vitro for autologous cell seeding.

  3. Design and analysis of reinforced fiber composites

    Yamagata, Nobuki


    The papers in this volume present a broad range of applications for reinforced fiber composites - from thin shell structures to tires. Linear and nonlinear structural behavior (from linear buckling to nonlinear yelding and fracture) are discussed as well as different materials are presented. Latest developments in computational methods for constructíons are presented which will help to save money and time. This is an edited collection of papers presented at a symposium at the WCCM, Barcelona, 2014.

  4. Multi-Length Scale-Enriched Continuum-Level Material Model for Kevlar®-Fiber-Reinforced Polymer-Matrix Composites

    Grujicic, M.; Pandurangan, B.; Snipes, J. S.; Yen, C.-F.; Cheeseman, B. A.


    Fiber-reinforced polymer matrix composite materials display quite complex deformation and failure behavior under ballistic/blast impact loading conditions. This complexity is generally attributed to a number of factors such as (a) hierarchical/multi-length scale architecture of the material microstructure; (b) nonlinear, rate-dependent and often pressure-sensitive mechanical response; and (c) the interplay of various intrinsic phenomena and processes such as fiber twisting, interfiber friction/sliding, etc. Material models currently employed in the computational engineering analyses of ballistic/blast impact protective structures made of this type of material do not generally include many of the aforementioned aspects of the material dynamic behavior. Consequently, discrepancies are often observed between computational predictions and their experimental counterparts. To address this problem, the results of an extensive set of molecular-level computational analyses regarding the role of various microstructural/morphological defects on the Kevlar® fiber mechanical properties are used to upgrade one of the existing continuum-level material models for fiber-reinforced composites. The results obtained show that the response of the material is significantly affected as a result of the incorporation of microstructural effects both under quasi-static simple mechanical testing condition and under dynamic ballistic-impact conditions.

  5. From Fragile to Resilient Insulation: Synthesis and Characterization of Aramid-Honeycomb Reinforced Silica Aerogel Composite Materials

    Marina Schwan


    Full Text Available The production of a new composite material embedding aramid honeycomb materials into nano-porous silica aerogels is studied. Our aim is to improve the poor mechanical strength of silica aerogels by aramid honeycombs without losing the amazing properties of the aerogels like little density and low thermal conductivity. The composite materials were prepared using two formulations of silica aerogels in combination with aramid honeycomb materials of different cell sizes. The silica aerogels are prepared using silicon alkoxides methyltrimethoxysilane and tetraethylorthosilicate as precursors in a two-step acid–base sol–gel process. Shortly in advance of the gelation point, the aramid honeycombs were fluted by the sol, gelation occurred and, after the aging process, the gel bodies were supercritically dried. The properties of the received composite materials are satisfying. Even the thermal conductivities and the densities are a bit higher than for pure aerogels. Most importantly, the mechanical strength is improved by a factor of 2.3 compared to aramid honeycomb materials and by a factor of 10 compared to the two silica aerogels themselves. The composite materials have a good prospective to be used as an impressive insulation material.



    Based on the study of strain distribution in short-fiber/whisker reinforced metal matrix composites, a deformation characteristic parameter λ is defined as the ratio of the root-mean-square strain of reinforcers to the macro-linear strain along the same direction. Quantitative relation between λ and microstructure parameters of the composite is obtained. As an example of applying and verifying λ, the stress-strain curve of [AlBO]w/Al composite under tensile loading is predicted and favorably compared with experiments. By using λ, the stiffness modulus of the composite with arbitrary reinforcer orientation under any loading condition is predicted from the microstructure parameters of material.

  7. On the Mechanical Properties of Hybrid Aluminium 7075 Matrix Composite Material Reinforced with SiC and TiC Produced by Powder Metallurgy Method

    S. Pradeep Devaneyan


    Full Text Available Metal matrix composites are widely used in components of various components of industrial equipment because of their superior material properties like high stiffness to weight ratio and high impact strength and fracture toughness while compared to the conventional material. Due to the concepts of high strength to low weight ratio, Al 7075 was extensively applied in aircraft engine and wings. Even if Al 7075 has higher hardness, higher strength, excellent wear resistance, and high-temperature corrosion protection, it is in need of further enhancement of properties for increasing its applicability. This paper presents the mechanical behavior of aluminium 7075 reinforced with Silicon Carbide (SiC and Titanium Carbide (TiC through powder metallurgy route. These specimens were produced by powder metallurgy method. The hybrid composite was made by Al 7075 alloy as the matrix with Silicon Carbide and Titanium Carbide as reinforcement. Silicon Carbide and Titanium Carbide are mixed in different weight ratio based on the design matrix formulated through a statistical tool, namely, Response Surface Methodology (RSM. Enhanced mechanical properties have been obtained with 90% of Al 7075, 4% of TiC, and 8% of SiC composition in the composite. Coefficient of friction appears to be more which has been determined by ring compression test.

  8. Aspects regarding the correlation between the physical-mechanical and tribological characteristics of composites materials reinforced with carbon fibers

    Caliman, R.


    The purpose of this paper is to highlight a number of factors that influence the physical-mechanical and tribological characteristics of sintered composite materials. Such factors are grouped generally in two categories: technological parameters (pressure compacting, sintering temperature, sintering duration, heat treatment) and the receipt of sintered composite materials. In this paper is presented a program of experiments developed both in composite materials sintered polymer matrix (non-metallic) and in the metal matrix (eg., Al) which was prepared in advance a methodology original production and research for this particular type of materials. The experiments have focused development and testing of a number of 14 polymer composite and 5 composite sintered Al base, in both situations armed with carbon fiber in various forms. Tribological tests followed the establishment of the coefficient of friction and wear rate of the sliding speed at the constant values (v = 7.2 mm/s) and the normal load (N = 8 daN) and for different orientations of the fibers to the direction of sliding: normal (N type), parallel (P) and antiparallel-perpendicular (AP type).

  9. Friction and wear behavior of carbon fiber reinforced brake materials

    Du-qing CHENG; Xue-tao WANG; Jian ZHU; Dong-bua QIU; Xiu-wei CHENG; Qing-feng GUAN


    A new composite brake material was fabri-cated with metallic powders, barium sulphate and modified phenolic resin as the matrix and carbon fiber as the reinforced material. The friction, wear and fade character-istics of this composite were determined using a D-MS friction material testing machine. The surface structure of carbon fiber reinforced friction materials was analyzed by scanning electronic microscopy (SEM). Glass fiber-reinforced and asbestos fiber-reinforced composites with the same matrix were also fabricated for comparison. The carbon fiber-reinforced friction materials (CFRFM) shows lower wear rate than those of glass fiber- and asbestos fiber-reinforced composites in the temperature range of 100℃-300℃. It is interesting that the frictional coefficient of the carbon fiber-reinforced friction materials increases as frictional temperature increases from 100℃ to 300℃, while the frictional coefficients of the other two composites decrease during the increasing temperatures. Based on the SEM observation, the wear mechanism of CFRFM at low temperatures included fiber thinning and pull-out. At high temperature, the phenolic matrix was degraded and more pull-out enhanced fiber was demonstrated. The properties of carbon fiber may be the main reason that the CFRFM possess excellent tribological performances.

  10. Experimental Investigation of Mechanical and Thermal properties of sisal fibre reinforced composite and effect of sic filler material

    Surya Teja, Malla; Ramana, M. V.; Sriramulu, D.; Rao, C. J.


    With a view of exploring the potential use of natural recourses, we made an attempt to fabricate sisal fibre polymer composites by hand lay-up method. Natural fiber composites are renewable, cheap and biodegradable. Their easy availability, lower density, higher specific properties, lower cost, satisfactory mechanical and thermal properties, non-corrosive nature, makes them an attractive ecological alternative to glass, carbon or other man-made synthetic fibers. In this work, the effect of SiC on mechanical and thermal properties of natural sisal fiber composites are investigated. The composite has been made with and without SiC incorporating natural sisal fiber with polyester as bonding material. The experimental outcomes exhibited that the tensile strength of composite with 10%SiC 2.53 times greater than that of composite without SiC. The impact strength of composite with 10% SiC is 1.73 times greater than that of composite without SiC plain polyester. Thermal properties studied include thermal conductivity, specific heat capacity, thermal diffusivity, thermal degradation and stability. Three different samples with 0%, 5%, 10% SiC powder are considered. With the addition of SiC filler powder, thermal conductivity increases, specific heat capacity gradually increases then decreases, thermal diffusivity increases and thermal stability improves with Sic powder.

  11. PEDOT:PSS-Based Piezo-Resistive Sensors Applied to Reinforcement Glass Fibres for in Situ Measurement during the Composite Material Weaving Process

    Damien Soulat


    Full Text Available The quality of fibrous reinforcements used in composite materials can be monitored during the weaving process. Fibrous sensors previously developed in our laboratory, based on PEDOT:PSS, have been adapted so as to directly measure the mechanical stress on fabrics under static or dynamic conditions. The objective of our research has been to develop new sensor yarns, with the ability to locally detect mechanical stresses all along the warp or weft yarn. This local detection is undertaken inside the weaving loom in real time during the weaving process. Suitable electronic devices have been designed in order to record in situ measurements delivered by this new fibrous sensor yarn.

  12. PEDOT:PSS-based piezo-resistive sensors applied to reinforcement glass fibres for in situ measurement during the composite material weaving process.

    Trifigny, Nicolas; Kelly, Fern M; Cochrane, Cédric; Boussu, François; Koncar, Vladan; Soulat, Damien


    The quality of fibrous reinforcements used in composite materials can be monitored during the weaving process. Fibrous sensors previously developed in our laboratory, based on PEDOT:PSS, have been adapted so as to directly measure the mechanical stress on fabrics under static or dynamic conditions. The objective of our research has been to develop new sensor yarns, with the ability to locally detect mechanical stresses all along the warp or weft yarn. This local detection is undertaken inside the weaving loom in real time during the weaving process. Suitable electronic devices have been designed in order to record in situ measurements delivered by this new fibrous sensor yarn.

  13. Composite materials design and applications

    Gay, Daniel; Tsai, Stephen W


    PART ONE. PRINCIPLES OF CONSTRUCTIONCOMPOSITE MATERIALS, INTEREST AND PROPERTIESWhat is Composite Material Fibers and MatrixWhat can be Made Using Composite Materials?Typical Examples of Interest on the Use of Composite MaterialsExamples on Replacing Conventional Solutions with CompositesPrincipal Physical PropertiesFABRICATION PROCESSESMolding ProcessesOther Forming ProcessesPractical Hints in the Manufacturing ProcessesPLY PROPERTIESIsotropy and AnisotropyCharacteristics of the Reinforcement-Matrix MixtureUnidirectional PlyWoven FabricsMats and Reinforced MatricesMultidimensional FabricsMetal Matrix CompositesTestsSANDWICH STRUCTURES:What is a Sandwich Structure?Simplified FlexureA Few Special AspectsFabrication and Design ProblemsNondestructive Quality ControlCONCEPTION AND DESIGNDesign of a Composite PieceThe LaminateFailure of LaminatesSizing of LaminatesJOINING AND ASSEMBLYRiveting and BoltingBondingInsertsCOMPOSITE MATERIALS AND AEROSPACE CONSTRUCTIONAircraftHelicoptersPropeller Blades for AirplanesTur...



    reported the impact of orientation on the manufacturing of polymer composite. ... strength when compared with the neat resin and other oriented (G10E30) fibre reinforced composite. ..... curing process on the properties of carbon fiber/epoxy composite fabricated using vacuum assisted resin infusion molding," Materials &.

  15. An Assessment of Self-Healing Fiber Reinforced Composites

    Smith, Joseph G., Jr.


    Several reviews and books have been written concerning self-healing polymers over the last few years. These have focused primarily on the types of self-healing materials being studied, with minor emphasis given to composite properties. The purpose of this review is to assess the self-healing ability of these materials when utilized in fiber reinforced composites

  16. Use of the Materials Genome Initiative (MGI approach in the design of improved-performance fiber-reinforced SiC/SiC ceramic-matrix composites (CMCs

    Jennifer S. Snipes


    Full Text Available New materials are traditionally developed using costly and time-consuming trial-and-error experimental efforts. This is followed by an even lengthier material-certification process. Consequently, it takes 10 to 20 years before a newly-discovered material is commercially employed. An alternative approach to the development of new materials is the so-called materials-by-design approach within which a material is treated as a complex hierarchical system, and its design and optimization is carried out by employing computer-aided engineering analyses, predictive tools and available material databases. In the present work, the materials-by-design approach is utilized to design a grade of fiber-reinforced (FR SiC/SiC ceramic matrix composites (CMCs, the type of materials which are currently being used in stationary components, and are considered for use in rotating components, of the hot sections of gas-turbine engines. Towards that end, a number of mathematical functions and numerical models are developed which relate CMC constituents’ (fibers, fiber coating and matrix microstructure and their properties to the properties and performance of the CMC as a whole. To validate the newly-developed materials-by-design approach, comparisons are made between experimentally measured and computationally predicted selected CMC mechanical properties. Then an optimization procedure is employed to determine the chemical makeup and processing routes for the CMC constituents so that the selected mechanical properties of the CMCs are increased to a preset target level.

  17. Time-resolved X-ray microtomographic measurement of water transport in wood-fibre reinforced composite material

    Miettinen, Arttu; Harjupatana, Tero; Kataja, Markku; Fortino, Stefania; Immonen, Kirsi


    Natural fibre composites are prone to absorb moisture from the environment which may lead to dimensional changes, mold growth, degradation of mechanical properties or other adverse effects. In this work we develop a method for direct non-intrusive measurement of local moisture content inside a material sample. The method is based on X-ray microtomography, digital image correlation and image analysis. As a first application of the method we study axial transport of water in a cylindrical polylactic acid/birch pulp composite material sample with one end exposed to water. Based on the results, the method seems to give plausible estimates of water content profiles inside the cylindrical sample. The results may be used, e.g., in developing and validating models of moisture transport in biocomposites.

  18. Nano polypeptide particles reinforced polymer composite fibers.

    Li, Jiashen; Li, Yi; Zhang, Jing; Li, Gang; Liu, Xuan; Li, Zhi; Liu, Xuqing; Han, Yanxia; Zhao, Zheng


    Because of the intensified competition of land resources for growing food and natural textile fibers, there is an urgent need to reuse and recycle the consumed/wasted natural fibers as regenerated green materials. Although polypeptide was extracted from wool by alkaline hydrolysis, the size of the polypeptide fragments could be reduced to nanoscale. The wool polypeptide particles were fragile and could be crushed down to nano size again and dispersed evenly among polymer matrix under melt extrusion condition. The nano polypeptide particles could reinforce antiultraviolet capability, moisture regain, and mechanical properties of the polymer-polypeptide composite fibers.

  19. Micromechanical modeling of strength and damage of fiber reinforced composites

    Mishnaevsky, L. Jr.; Broendsted, P.


    The report for the first year of the EU UpWind project includes three parts: overview of concepts and methods of modelling of mechanical behavior, deformation and damage of unidirectional fiber reinforced composites, development of computational tools for the automatic generation of 3D micromechanical models of fiber reinforced composites, and micromechanical modelling of damage in FRC, and phenomenological analysis of the effect of frequency of cyclic loading on the lifetime and damage evolution in materials. (au)

  20. Painted Fiberglass-Reinforced Contemporary Sculpture: Investigating Composite Materials, Techniques and Conservation Using a Multi-Analytical Approach.

    Salvadori, Barbara; Cantisani, Emma; Colombini, Maria Perla; Tognon, Cecilia Gaia Rachele


    A multi-analytical approach was used to study the constituent materials, manufacturing technique, and state of conservation of a contemporary sculpture. This sculpture, entitled Nuredduna, was created by Aligi Sassu in 1995 and is located in the "Bellariva garden" in Florence (Italy). Fourier transform infrared spectroscopy (FT-IR), optical and electronic microscopy (OM and SEM-EDS), X-ray diffraction (XRD), and portable X-ray fluorescence (XRF) highlighted the multi-layered structure of the statue: fiberglass and an overlay of different layers (gel coat) applied with an unsaturated polyester resin added with aggregate materials and bromine compounds. A top-coat in acrylic black varnish, used as a finish, was also found. The combination of these materials with their different compositions, environmental impact, and even vandalism have negatively affected the state of conservation of Nuredduna, causing the loss of strata in its lower parts (legs and feet).

  1. Reinforced polypropylene composites: effects of chemical compositions and particle size.

    Ashori, Alireza; Nourbakhsh, Amir


    In this work, the effects of wood species, particle sizes and hot-water treatment on some physical and mechanical properties of wood-plastic composites were studied. Composites of thermoplastic reinforced with oak (Quercus castaneifolia) and pine (Pinus eldarica) wood were prepared. Polypropylene (PP) and maleic anhydride grafted polypropylene (MAPP) were used as the polymer matrix and coupling agent, respectively. The results showed that pine fiber had significant effect on the mechanical properties considered in this study. This effect is explained by the higher fiber length and aspect ratio of pine compared to the oak fiber. The hot-water treated (extractive-free) samples, in both wood species, improved the tensile, flexural and impact properties, but increased the water absorption for 24h. This work clearly showed that lignocellulosic materials in both forms of fiber and flour could be effectively used as reinforcing elements in PP matrix. Furthermore, extractives have marked effects on the mechanical and physical properties.

  2. Effects of different surface treatments on the bond strength of glass fiber-reinforced composite root canal posts to composite core material

    Murat Kurt


    Conclusion: Er:YAG laser treatments on the FRC post surface decreased the bond strength. Airborne-particle abrasion and HF acid etching are alternative methods for increasing bond strength of FRC posts to composite core material.

  3. An analysis of the abaca natural fiber in reinforcing concrete composites as a construction material in developing countries

    Magdamo, R.V.


    This study analyzed the flexural and splitting tensile strengths and the ductility of abaca fiber-reinforced concrete composites. Abaca fibers are natural fibers of vegetable origin from the abaca plant native to the Philippine Islands. The purpose was to investigate how various volume-fractions of the abaca fiber could affect the mechanical properties of the concrete matrix. A concrete design mix containing a volume ratio of 1.0 part Type I Portland cement and 3.0 parts sand was used in the preparation of laboratory test samples. Abaca fibers were 1 to 1.5 inches long and randomly mixed with the concrete at 0.2% and 0.4% volume fractions. The fibers were not chemically treated and no admixtures were used. Samples were cast into concrete cylinders and flexural beams. Standard ASTM procedures in casting of flexural beams and concrete cylinders and the curing of 28-day concrete samples were followed. The center-point loading method of the flexural test and the splitting tensile test was utilized. Addition of abaca fibers decreased the mean flexural and splitting tensile strengths of the concrete matrices. However, ductility of the matrices increased with the addition of abaca fibers at 0.2% and 0.4% volume-fractions. The Scanning Electron Microscope (SEM) micrographs revealed that increasing the fiber volume-fraction influenced the growth rate of dehydration precipitates as CH (calcium hydroxide) crystals. At the 0.2% volume-fraction, smaller density of precipitates grew into large crystals, while at the 0.4% volume-fraction, the dehydration precipitates were much more dense, which were made up of small sized crystals. Abaca fibers in the concrete mix decreased the mean flexural and splitting tensile strengths, increased the modulus of elasticity, improved the ductility, and acted as a medium to slow down and stop the propagation of cracks.

  4. Impact property of W fiber reinforced amorphous composite material%钨丝/非晶复合材料的冲击性能研究

    王振明; 史洪刚; 冯宏伟; 尚福军; 祝理君; 苏继红


    对钨丝增强锆基非晶复合材料在不同温度下的冲击性能进行试验,研究钨丝非晶复合材料的断裂方式,与钨合金比较两者不同的断口形貌.结果表明,钨丝/非晶复合材料冲击韧性低于钨合金,但其受低温影响较小,在-40℃下的冲击功和常温相比基本不变.冲击断口主要有钨丝和非晶基体的剥离,非晶基体的断裂,钨丝的断裂(其中钨丝在横向断裂时有时伴有纵向裂纹)3种断裂方式.%Impact experiment of the W fiber reinforced amorphous composite material was made at different temperature.Comparison of fracture mode and feature with tungsten alloy was made. The results show that the impact proterty of W fiber amorphous composite material is lower than that of tungsten alloy and it is not affected by low temperature. The fracture of W fiber amorphous composite material includes three patterns:the peeling of W fiber from amorphous alloy;the fracture of amorphous alloy; the fracture of W fiber,with longitudinal crack sometimes.

  5. Designing bioinspired composite reinforcement architectures via 3D magnetic printing

    Martin, Joshua J.; Fiore, Brad E.; Erb, Randall M.


    Discontinuous fibre composites represent a class of materials that are strong, lightweight and have remarkable fracture toughness. These advantages partially explain the abundance and variety of discontinuous fibre composites that have evolved in the natural world. Many natural structures out-perform the conventional synthetic counterparts due, in part, to the more elaborate reinforcement architectures that occur in natural composites. Here we present an additive manufacturing approach that combines real-time colloidal assembly with existing additive manufacturing technologies to create highly programmable discontinuous fibre composites. This technology, termed as `3D magnetic printing', has enabled us to recreate complex bioinspired reinforcement architectures that deliver enhanced material performance compared with monolithic structures. Further, we demonstrate that we can now design and evolve elaborate reinforcement architectures that are not found in nature, demonstrating a high level of possible customization in discontinuous fibre composites with arbitrary geometries.

  6. Modeling of properties of fiber reinforced cement composites

    Jevtić Dragica


    Full Text Available This paper presents the results of authors' laboratory testing of the influence of steel fibers as fiber reinforcement on the change of properties of cement composite mortar and concrete type materials. Mixtures adopted - compositions of mortars had identical amounts of components: cement, sand and silica fume. The second type of mortar contained 60 kg/m3 of fiber reinforcement, as well as the addition of the latest generation of superplasticizer. Physical and mechanical properties of fiber reinforced mortars and etalon mixtures (density, flexural strength, compressive strength were compared. Tests on concrete type cement composites included: density, mechanical strengths and the deformation properties. The tests showed an improvement in the properties of fiber reinforced composites.

  7. Composites reinforcement by rods: a SAS study

    Urban, V. [ESRF, BP220, 38043 Grenoble Cedex (France); Botti, A.; Pyckhout-Hintzen, W.; Richter, D. [IFF-Forschungszentrum Juelich, 52425 Juelich (Germany); Straube, E. [University of Halle, FB Physik, 06099 Halle (Germany)


    The mechanical properties of composites are governed by size, shape and dispersion degree of so-called reinforcing particles. Polymeric fillers based on thermodynamically driven microphase separation of block copolymers offer the opportunity to study a model system of controlled rod-like filler particles. We chose a triblock copolymer (PBPSPB) and carried out SAS measurements with both X-rays and neutrons, in order to characterize separately the hard phase and the cross-linked PB matrix. The properties of the material depend strongly on the way that stress is carried and transferred between the soft matrix and the hard fibers. The failure of the strain-amplification concept and the change of topological contributions to the free energy and scattering factor have to be addressed. In this respect the composite shows a similarity to a two-network system, i.e. interpenetrating rubber and rod-like filler networks. (orig.)

  8. Composites reinforcement by rods a SAS study

    Urban, V; Pyckhout-Hintzen, W; Richter, D; Straube, E


    The mechanical properties of composites are governed by size, shape and dispersion degree of so-called reinforcing particles. Polymeric fillers based on thermodynamically driven microphase separation of block copolymers offer the opportunity to study a model system of controlled rod-like filler particles. We chose a triblock copolymer (PBPSPB) and carried out SAS measurements with both X-rays and neutrons, in order to characterize separately the hard phase and the cross-linked PB matrix. The properties of the material depend strongly on the way that stress is carried and transferred between the soft matrix and the hard fibers. The failure of the strain-amplification concept and the change of topological contributions to the free energy and scattering factor have to be addressed. In this respect the composite shows a similarity to a two-network system, i.e. interpenetrating rubber and rod-like filler networks. (orig.)

  9. Continuous fiber-reinforced titanium aluminide composites

    Mackay, R. A.; Brindley, P. K.; Froes, F. H.


    An account is given of the fabrication techniques, microstructural characteristics, and mechanical behavior of a lightweight, high service temperature SiC-reinforced alpha-2 Ti-14Al-21Nb intermetallic-matrix composite. Fabrication techniques under investigation to improve the low-temperature ductility and environmental resistance of this material system, while reducing manufacturing costs to competitive levels, encompass powder-cloth processing, foil-fiber-foil processing, and thermal-spray processing. Attention is given to composite microstructure problems associated with fiber distribution and fiber-matrix interfaces, as well as with mismatches of thermal-expansion coefficient; major improvements are noted to be required in tensile properties, thermal cycling effects, mechanical damage, creep, and environmental effects.

  10. Preparation and characterisation of poly p-phenylene-2,6-benzobisoxazole fibre-reinforced resin matrix composite for endodontic post material: a preliminary study.

    Hu, Chen; Wang, Feng; Yang, Huiyong; Ai, Jun; Wang, Linlin; Jing, Dongdong; Shao, Longquan; Zhou, Xingui


    Currently used fibre-reinforced composite (FRC) intracanal posts possess low flexural strength which usually causes post fracture when restoring teeth with extensive loss. To improve the flexural strength of FRC, we aimed to apply a high-performance fibre, poly p-phenylene-2, 6-benzobisoxazole (PBO), to FRCs to develop a new intracanal post material. To improve the interfacial adhesion strength, the PBO fibre was treated with coupling agent (Z-6040), argon plasma, or a combination of above two methods. The effects of the surface modifications on PBO fibre were characterised by determining the single fibre tensile strength and interfacial shear strength (IFSS). The mechanical properties of PBO FRCs were characterised by flexural strength and flexural modulus. The cytotoxicity of PBO FRC was evaluated by the MTT assay. Fibres treated with a combination of Z-6040 and argon plasma possessed a significantly higher IFSS than untreated fibres. Fibre treated with the combination of Z-6040-argon-plasma FRC had the best flexural strength (531.51 ± 26.43MPa) among all treated fibre FRCs and had sufficient flexural strength and appropriate flexural moduli to be used as intracanal post material. Furthermore, an in vitro cytotoxicity assay confirmed that PBO FRCs possessed an acceptable level of cytotoxicity. In summary, our study verified the feasibility of using PBO FRC composites as new intracanal post material. Although the mechanical property of PBO FRC still has room for improvement, our study provides a new avenue for intracanal post material development in the future. To our knowledge, this is the first study to verify the feasibility of using PBO FRC composites as new intracanal post material. Our study provided a new option for intracanal post material development. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Thermoforming of Continuous Fibre Reinforced Thermoplastic Composites

    McCool, Raurí; Murphy, Adrian; Wilson, Ryan; Jiang, Zhenyu; Price, Mark


    The introduction of new materials, particularly for aerospace products, is not a simple, quick or cheap task. New materials require extensive and expensive qualification and must meet challenging strength, stiffness, durability, manufacturing, inspection and maintenance requirements. Growth in industry acceptance for fibre reinforced thermoplastic composite systems requires the determination of whole life attributes including both part processing and processed part performance data. For thermoplastic composite materials the interactions between the processing parameters, in-service structural performance and end of life recyclability are potentially interrelated. Given the large number and range of parameters and the complexity of the potential relationships, understanding for whole life design must be developed in a systematic building block approach. To assess and demonstrate such an approach this article documents initial coupon level thermoforming trials for a commercially available fibre reinforced thermoplastic laminate, identifying the key interactions between processing and whole life performance characteristics. To examine the role of the thermoforming process parameters on the whole life performance characteristics of the formed part requires a series of manufacturing trials combined with a series of characterisation tests on the manufacturing trial output. Using a full factorial test programme and considering all possible process parameters over a range of potential magnitudes would result in a very large number of manufacturing trials and accompanying characterisation tests. Such an approach would clearly be expensive and require significant time to complete, therefore failing to address the key requirement for a future design methodology capable of rapidly generating design knowledge for new materials and processes. In this work the role of mould tool temperature and blank forming temperature on the thermoforming of a commercially available

  12. Recent progress in NASA Langley textile reinforced composites program

    Dexter, H. Benson; Harris, Charles E.; Johnston, Norman J.


    The NASA LaRC is conducting and sponsoring research to explore the benefits of textile reinforced composites for civil transport aircraft primary structures. The objective of this program is to develop and demonstrate the potential of affordable textile reinforced composite materials to meet design properties and damage tolerance requirements of advanced aircraft structural concepts. In addition to in-house research, the program was recently expanded to include major participation by the aircraft industry and aerospace textile companies. The major program elements include development of textile preforms, processing science, mechanics of materials, experimental characterization of materials, and development and evaluation of textile reinforced composite structural elements and subcomponents. The NASA Langley in-house focus is as follows: development of a science-based understanding of resin transfer molding (RTM), development of powder-coated towpreg processes, analysis methodology, and development of a performance database on textile reinforced composites. The focus of the textile industry participation is on development of multidirectional, damage-tolerant preforms, and the aircraft industry participation is in the areas of design, fabrication and testing of textile reinforced composite structural elements and subcomponents. Textile processes such as 3D weaving, 2D and 3D braiding, and knitting/stitching are being compared with conventional laminated tape processes for improved damage tolerance. Through-the-thickness reinforcements offer significant damage tolerance improvements. However, these gains must be weighed against potential loss in in-plane properties such as strength and stiffness. Analytical trade studies are underway to establish design guidelines for the application of textile material forms to meet specific loading requirements. Fabrication and testing of large structural components are required to establish the full potential of textile reinforced

  13. SNAP-TITE Composite Column Reinforcement

    ECT Team, Purdue


    Recent earthquakes throughout the world have demonstrated the vulnerabilities of older reinforced concrete columns to seismic deformation demands. The Snap Tite Composite Column Reinforcement strengthens a concrete column by confining it in an external composite jacket, which prevents the concrete from expanding during seismic activity or prolonged freeze-thaw cycles. The pre-manufactured fiberglass jacket is comprised of glass fibers and corrosion resistant isopolyester resins.

  14. Fiber-reinforced composites in fixed partial dentures

    Vallittu P


    Full Text Available Fiber-reinforced composite resin (FRC prostheses offer the advantages of good esthetics, minimal invasive treatment, and an ability to bond to the abutment teeth, thereby compensating for less-than-optimal abutment tooth retention and resistance form. These prostheses are composed of two types of composite materials: fiber composites to build the framework and hybrid or microfill particulate composites to create the external veneer surface. This review concentrates on the use of fiber reinforcement in the fabrication of laboratory or chairside-made composite-fixed partial dentures of conventional preparation. Other applications of FRC in dentistry are briefly mentioned. The possibilities fiber reinforcement technology offers must be emphasized to the dental community. Rather than limiting discussion to whether FRC prostheses will replace metal-ceramic or full-ceramic prostheses, attention should be focused on the additional treatment options brought by the use of fibers. However, more clinical experience is needed.

  15. Homogenization of long fiber reinforced composites including fiber bending effects

    Poulios, Konstantinos; Niordson, Christian Frithiof


    This paper presents a homogenization method, which accounts for intrinsic size effects related to the fiber diameter in long fiber reinforced composite materials with two independent constitutive models for the matrix and fiber materials. A new choice of internal kinematic variables allows...... of the reinforcing fibers is captured by higher order strain terms, resulting in an accurate representation of the micro-mechanical behavior of the composite. Numerical examples show that the accuracy of the proposed model is very close to a non-homogenized finite-element model with an explicit discretization...

  16. [Carbon fiber-reinforced plastics as implant materials].

    Bader, R; Steinhauser, E; Rechl, H; Siebels, W; Mittelmeier, W; Gradinger, R


    Carbon fiber-reinforced plastics have been used clinically as an implant material for different applications for over 20 years.A review of technical basics of the composite materials (carbon fibers and matrix systems), fields of application,advantages (e.g., postoperative visualization without distortion in computed and magnetic resonance tomography), and disadvantages with use as an implant material is given. The question of the biocompatibility of carbon fiber-reinforced plastics is discussed on the basis of experimental and clinical studies. Selected implant systems made of carbon composite materials for treatments in orthopedic surgery such as joint replacement, tumor surgery, and spinal operations are presented and assessed. Present applications for carbon fiber reinforced plastics are seen in the field of spinal surgery, both as cages for interbody fusion and vertebral body replacement.

  17. Field survey and laboratory tests on composite materials case of GRP (Glass Fiber Reinforced Polyester tubes for water suply

    Radu Hariga


    Full Text Available In the Moldova land, were made two lines of water adduction, having 6000 m length and 40 m slope, or 1/150 slope. The water supply component tubes were disposed under the plant: The tubes are made of glass – reinforced thermosetting plastics (GRP. After about 180 days of operation, one of the lines showed severe deterioration of the quality pipe components. This paper deals with some laboratory tests in order to detect the failure cases of the pipelines components.

  18. Chairside fabricated fiber-reinforced composite fixed partial denture

    Garoushi, Sufyan; Vallittu, Pekka K


    The advances in the materials and techniques for adhesive dentistry have allowed the development of non-invasive or minimally invasive approaches for replacing a missing tooth in those clinical situations when conservation of adjacent teeth is needed. Good mechanical and cosmetic/aesthetic properties of fiber-reinforced composite (FRC), with good bonding properties with composite resin cement and veneering composite are needed in FRC devices. Some recent studies have shown that adhesives of c...

  19. Metal Matrix Composites Reinforced by Nano-Particles—A Review

    Riccardo Casati


    Full Text Available Metal matrix composites reinforced by nano-particles are very promising materials, suitable for a large number of applications. These composites consist of a metal matrix filled with nano-particles featuring physical and mechanical properties very different from those of the matrix. The nano-particles can improve the base material in terms of wear resistance, damping properties and mechanical strength. Different kinds of metals, predominantly Al, Mg and Cu, have been employed for the production of composites reinforced by nano-ceramic particles such as carbides, nitrides, oxides as well as carbon nanotubes. The main issue of concern for the synthesis of these materials consists in the low wettability of the reinforcement phase by the molten metal, which does not allow the synthesis by conventional casting methods. Several alternative routes have been presented in literature for the production of nano-composites. This work is aimed at reviewing the most important manufacturing techniques used for the synthesis of bulk metal matrix nanocomposites. Moreover, the strengthening mechanisms responsible for the improvement of mechanical properties of nano-reinforced metal matrix composites have been reviewed and the main potential applications of this new class of materials are envisaged.

  20. PMMA-based composite materials with reactive ceramic fillers: part III: radiopacifying particle-reinforced bone cements.

    Abboud, M; Vol, S; Duguet, E; Fontanille, M


    New acrylic bone cements were prepared from alumina particles previously treated by 3-(trimethoxysilyl)propylmethacrylate (gamma-MPS), able to act both as radiopacifying and reinforcing agents. The present study deals with the handling characteristics and the compressive behavior of such cements. The influence of the particles morphology, their surface-modification by gamma-MPS bonding agent, their concentration in the cement, the powder-to-liquid ratio and the benzoyl peroxide concentration are reported. The role of grafted gamma-MPS molecules as coupling agent was confirmed. For several formulations, compressive strength and modulus reached 150 MPa and 3400 MPa respectively. Limitations in the use of such formulations are also comprehensively discussed.

  1. Development of Flax Fibre based Textile Reinforcements for Composite Applications

    Goutianos, S.; Peijs, T.; Nystrom, B.; Skrifvars, M.


    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 current work aims to develop high-performance natural fibre composite systems for structural applications using continuous textile reinforcements like UD-tapes or woven fabrics. One of the main problems 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 cannot 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. Therefore, an optimum twist should be used to balance processability and mechanical properties. Subsequently, different types of fabrics (i.e., biaxial plain weaves, unidirectional fabrics and non-crimp fabrics) were produced and evaluated as reinforcement in composites manufactured by well established manufacturing techniques such as hand lay-up, vacuum infusion, pultrusion and resin transfer moulding (RTM). Clearly, as expected, the developed materials cannot directly compete in terms of strength with glass fibre composites. However, they are clearly able to compete with these materials in terms of stiffness, especially if the low density of flax is taken into account. Their properties are however very favourable when compared with non-woven glass composites.

  2. Tungsten fiber reinforced copper matrix composites: A review

    Mcdanels, David L.


    Tungsten fiber reinforced copper matrix (W/Cu) composites have served as an ideal model system with which to analyze the properties of metal matrix composites. A series of research programs were conducted to investigate the stress-strain behavior of W/Cu composites; the effect of fiber content on the strength, modulus, and conductivity of W/Cu composites; and the effect of alloying elements on the behavior of tungsten wire and of W/Cu composites. Later programs investigated the stress-rupture, creep, and impact behavior of these composites at elevated temperatures. Analysis of the results of these programs as allows prediction of the effects of fiber properties, matrix properties, and fiber content on the properties of W/Cu composites. These analyses form the basis for the rule-of-mixtures prediction of composite properties which was universally adopted as the criteria for measuring composite efficiency. In addition, the analyses allows extrapolation of potential properties of other metal matrix composites and are used to select candidate fibers and matrices for development of tungsten fiber reinforced superalloy composite materials for high temperature aircraft and rocket engine turbine applications. The W/Cu composite efforts are summarized, some of the results obtained are described, and an update is provided on more recent work using W/Cu composites as high strength, high thermal conductivity composite materials for high heat flux, elevated temperature applications.

  3. Characterisation of Natural Fibre Reinforcements and Composites

    Richard K. Cullen


    Full Text Available Recent EU directives (e.g., ELV and WEEE have caused some rethinking of the life cycle implications of fibre reinforced polymer matrix composites. Man-made reinforcement fibres have significant ecological implications. One alternative is the use of natural fibres as reinforcements. The principal candidates are bast (plant stem fibres with flax, hemp, and jute as the current front runners. The work presented here will consider the characterisation of jute fibres and their composites. A novel technique is proposed for the measurement of fibre density. The new rule of mixtures, extended for noncircular cross-section natural fibres, is shown to provide a sensible estimate for the experimentally measured elastic modulus of the composite.

  4. Carbon Nanomaterials as Reinforcements for Composites

    Zhu, Shen; Su, Ching-Hua; Lehoczky, S. L.; Curreri, Peter A. (Technical Monitor)


    Carbon nanomaterials including fellerenes, nanotubes (CNT) and nanofibers have been proposed for many applications. One of applications is to use the carbon nanomaterials as reinforcements for composites, especially for polymer matrices. Carbon nanotubes is a good reinforcement for lightweight composite applications due to its low mass density and high Young's modulus. Two obscures need to overcome for carbon nanotubes as reinforcements in composites, which are large quantity production and functioning the nanotubes. This presentation will discuss the carbon nanotube growth by chemical vapor deposition. In order to reduce the cost of producing carbon nanotubes as well as preventing the sliding problems, carbon nanotubes were also synthesized on carbon fibers. The synthesis process and characterization results of nanotubes and nanotubes/fibers will be discussed in the presentation.

  5. Mechanically milled aluminium matrix composites reinforced with halloysite nanotubes

    L.A. Dobrzański


    Full Text Available Purpose: The present work describes fabrication of aluminium AlMg1SiCu matrix composite materials reinforced with halloysite nanotubes by powder metallurgy techniques and hot extrusion.Design/methodology/approach: Mechanical milling, compacting and hot extrusion successively are considering as a method for manufacturing metal composite powders with a controlled fine microstructure and enhanced mechanical properties. It is possible by the repeated welding and fracturing of powders particles mixture in a highly energetic ball mill.Findings: The milling process has a huge influence on the properties of powder materials, changing the spherical morphology of as-received powder during milling process to flattened one due to particle deformation followed by welding and fracturing particles of deformed and hardened enough which allows to receive equiaxial particles morphology again. The investigation shows that so called brittle mineral particles yields to plastic deformation as good as ductile aluminium alloy particles. That indicates that the halloysite powder can play a role of the accelerator during mechanical milling. High energy ball milling as a method of mechanical milling improves the distribution of the halloysite reinforcing particles throughout the aluminium matrix, simultaneously reducing the size of particles. The apparent density changes versus milling time can be used to control the composite powders production by mechanical milling and the presence of halloysite reinforcements particles accelerates the mechanical milling process.Research limitations/implications: Contributes to knowledge about technology, structure and properties of aluminium alloy matrix composite material reinforced with mineral nanoparticles.Practical implications: Conducted research shows that applied technology allows obtaining very good microstructural characteristics.Originality/value: It has been confirmed that halloysite nanotubes can be applied as an effective

  6. Energy-related application of composite material. Carbon fiber reinforced plastics (CFRP); Enerugi kanren yoto to CFRP

    Higuchi, T. [Toray Industries, Tokyo (Japan)


    Carbon fiber reinforced plastics (CFRP) with advantages such as high strength, high relative elastic modulus, high chemical stability, and excellent thermal/electric properties, is widely used in aviation/space, sports, and industries. This paper takes up CNG tank, flywheel, and windmill blade, as examples of energy-related application development. For the purpose of weight reduction of CNG car, big three car manufacturers of the U.S. and Honda adopted CNG tank. Flywheel with CFRP rotor can store 3.8 times energy compared with that of steel. Windmill blade used in windmill power generation is mostly made of 3 blades and presently GFRP is used, but CFRP will become a main stream when the windmill is scaled up. In the future, it is necessary to reduce the cost of carbon fiber and its treatment process, as well as to solve the targets such as standardization of design, recognition by users, and verification in environmental use, and to develop further applications. (NEDO)

  7. Fracture of fiber-reinforced composites analyzed via acoustic emission.

    Ereifej, Nadia S; Oweis, Yara G; Altarawneh, Sandra K


    This study investigated the fracture resistance of composite resins using a three-point bending test and acoustic emission (AE) analysis. Three groups of specimens (n=15) were prepared: non-reinforced BelleGlass HP composite (NRC), unidirectional (UFRC) and multidirectional (MFRC) fiber-reinforced groups which respectively incorporated unidirectional Stick and multidirectional StickNet fibers. Specimens were loaded to failure in a universal testing machine while an AE system was used to detect audible signals. Initial fracture strengths and AE amplitudes were significantly lower than those at final fracture in all groups (pcomposite resin materials and the monitoring of acoustic signals revealed significant information regarding the fracture process.

  8. Fabrication and characterization of S. cilliare fibre reinforced polymer composites

    A S Singha; Vijay Kumar Thakur


    In the recent times, there has been an ever-increasing interest in green composite materials for its applications in the field of industries, aerospace, sports, household etc and in many other fields. In this paper, fabrication of Saccharum cilliare fibre reinforced green polymer composites using resorcinol formaldehyde (RF) as a novel matrix has been reported. A systematic approach for processing of polymer is presented. Effect of fibre loading on mechanical properties like flexural, tensile, compressive and wear resistances has also been determined. Reinforcing of the RF resin with Saccharum cilliare (SC) fibre was done in the form of particle size (200 micron). Present work reveals that mechanical properties of the RF resin have been found to increase up to 30% fibre loading and then decreases. Morphological and thermal studies of the resin, fibre and particle reinforced (P-Rnf) green composites have also been studied.

  9. Obtaining New Dental Materials Reinforced with Carbon Nanotubes

    I.V. Zaporotskova


    Full Text Available The article seeks to explore the change of strength properties of composite polymer material on the basis of fast-hardening dental plastic "Carbogen", when reinforcing its coal-native nanotubes. Were discussed peculiarities of composition of Carboante, ways of creation of polymeric composition deposits by doping their carbon nanotubes, the results of measuring the strength characteristic characteristics obtained new polymer materials. On the basis of the analysis of the practical and the theoretical-sky research, conclusions were drawn on the feasibility of a new filling material with the use of carbon nanotubes with unique strength characteristics and use of their in dentistry.

  10. Polymer Composites Reinforced by Nanotubes as Scaffolds for Tissue Engineering

    Wei Wang


    Full Text Available The interest in polymer based composites for tissue engineering applications has been increasing in recent years. Nanotubes materials, including carbon nanotubes (CNTs and noncarbonic nanotubes, with unique electrical, mechanical, and surface properties, such as high aspect ratio, have long been recognized as effective reinforced materials for enhancing the mechanical properties of polymer matrix. This review paper is an attempt to present a coherent yet concise review on the mechanical and biocompatibility properties of CNTs and noncarbonic nanotubes/polymer composites, such as Boron nitride nanotubes (BNNTs and Tungsten disulfide nanotubes (WSNTs reinforced polymer composites which are used as scaffolds for tissue engineering. We also introduced different preparation methods of CNTs/polymer composites, such as in situ polymerization, solution mixing, melt blending, and latex technology, each of them has its own advantages.

  11. Exploration of a Chemo-Mechanical Technique for the Isolation of Nanofibrillated Cellulosic Fiber from Oil Palm Empty Fruit Bunch as a Reinforcing Agent in Composites Materials

    Ireana Yusra A. Fatah


    Full Text Available The aim of the present study was to determine the influence of sulphuric acid hydrolysis and high-pressure homogenization as an effective chemo-mechanical process for the isolation of quality nanofibrillated cellulose (NFC. The cellulosic fiber was isolated from oil palm empty fruit bunch (OPEFB using acid hydrolysis methods and, subsequently, homogenized using a high-pressure homogenizer to produce NFC. The structural analysis and the crystallinity of the raw fiber and extracted cellulose were carried out by Fourier transform infrared spectroscopy (FT-IR and X-ray diffraction (XRD. The morphology and thermal stability were investigated by scanning electron microscopy (SEM, transmission electron microscopy (TEM and thermogravimetric (TGA analyses, respectively. The FTIR results showed that lignin and hemicellulose were removed effectively from the extracted cellulose nanofibrils. XRD analysis revealed that the percentage of crystallinity was increased from raw EFB to microfibrillated cellulose (MFC, but the decrease for NFC might due to a break down the hydrogen bond. The size of the NFC was determined within the 5 to 10 nm. The TGA analysis showed that the isolated NFC had high thermal stability. The finding of present study reveals that combination of sulphuric acid hydrolysis and high-pressure homogenization could be an effective chemo-mechanical process to isolate cellulose nanofibers from cellulosic plant fiber for reinforced composite materials.

  12. Woven Structures from Natural Fibres for Reinforcing Composites

    Maniņš, M; Bernava, A; Strazds, G.


    The increase of production of woven structures from natural fibres for reinforced composites can be noticed in different sectors of economy. This can be explained by limited sources of raw materials and different environmental issues, as well as European Union guidelines for car manufacture [4]. This research produced 2D textile structures of hemp yarn and polypropylene yarn and tested the impact of added glass fibre yarn on the mechanical properties of the woven structures and the composites...

  13. Fiber-reinforced bioactive and bioabsorbable hybrid composites

    Huttunen, Mikko; Godinho, Pedro; Kellomaeki, Minna [Tampere University of Technology, Institute of Biomaterials, Hermiankatu 12, PO Box 589, FIN-33101 Tampere (Finland); Toermaelae, Pertti [Bioretec Ltd, Hermiankatu 22, PO Box 135, FI-33721 Tampere (Finland)], E-mail:


    Bioabsorbable polymeric bone fracture fixation devices have been developed and used clinically in recent decades to replace metallic implants. An advantage of bioabsorbable polymeric devices is that these materials degrade in the body and the degradation products exit via metabolic routes. Additionally, the strength properties of the bioabsorbable polymeric devices decrease as the device degrades, which promotes bone regeneration (according to Wolff's law) as the remodeling bone tissue is progressively loaded. The most extensively studied bioabsorbable polymers are poly-{alpha}-hydroxy acids. The major limitation of the first generation of bioabsorbable materials and devices was their relatively low mechanical properties and brittle behavior. Therefore, several reinforcing techniques have been used to improve the mechanical properties. These include polymer chain orientation techniques and the use of fiber reinforcements. The latest innovation for bioactive and fiber-reinforced bioabsorbable composites is to use both bioactive and bioresorbable ceramic and bioabsorbable polymeric fiber reinforcement in the same composite structure. This solution of using bioactive and fiber-reinforced bioabsorbable hybrid composites is examined in this study.

  14. Advanced Single-Polymer Nanofiber-Reinforced Composite - Towards Next Generation Ultralight Superstrong/Tough Structural Material


    single- polymer nanocomposite. This approach was enabled by the versatility of polyimide chemistry . In addition to very good material compatibility and...synthesis and self-assembly of giant surfactants based on polyhedral oligomeric selsesquioxane-polymer conjugates, University of Akron, 2013 (Advisor...Kaohusing, Taiwan, November 2013. • Stephen Z. D. Cheng, Giant polyhedra and giant surfactants based on nano-atoms: Tuning from crystals, to

  15. Micromechanical failure in fiber-reinforced composites

    Ashouri Vajari, Danial

    Micromechanical failure mechanisms occurring in unidirectional fiber-reinforced composites are studied by means of the finite element method as well as experimental testing. This study highlights the effect of micro-scale features such as fiber/matrix interfacial debonding, matrix cracking and mi...

  16. Working mechanism of two-direction reinforced composite foundation

    ZHANG Ling; ZHAO Ming-hua; HE Wei


    Based on the discussion about working mechanism of horizontal reinforcement and that of vertical reinforcement,respectively, the working mechanism of two-direction reinforced composite foundation was studied. The enhancing effect of horizontal reinforcement on vertical reinforced composite foundation was analyzed. A simplified calculation method for such two-direction reinforced working system was presented. A model experiment was carried out to validate the proposed method. In the experiment, geocell reinforcement worked as the horizontal reinforcement, while gravel pile composite foundation worked as the vertical reinforcement. The results show that the calculated curve is close to the measured one. The installation of geosynthetic reinforcement can increase the bearing capacity of composite foundation by nearly 68% at normal foundation settlement, which suggests that the enhancing effect by geosynthetic reinforcement should be taken into account in current design/analysis methods.

  17. New generation fiber reinforced polymer composites incorporating carbon nanotubes

    Soliman, Eslam

    The last five decades observed an increasing use of fiber reinforced polymer (FRP) composites as alternative construction materials for aerospace and infrastructure. The high specific strength of FRP attracted its use as non-corrosive reinforcement. However, FRP materials were characterized with a relatively low ductility and low shear strength compared with steel reinforcement. On the other hand, carbon nanotubes (CNTs) have been introduced in the last decade as a material with minimal defect that is capable of increasing the mechanical properties of polymer matrices. This dissertation reports experimental investigations on the use of multi-walled carbon nanotubes (MWCNTs) to produce a new generation of FRP composites. The experiments showed significant improvements in the flexure properties of the nanocomposite when functionalized MWCNTs were used. In addition, MWCNTs were used to produce FRP composites in order to examine static, dynamic, and creep behavior. The MWCNTs improved the off-axis tension, off-axis flexure, FRP lap shear joint responses. In addition, they reduced the creep of FRP-concrete interface, enhanced the fracture toughness, and altered the impact resistance significantly. In general, the MWCNTs are found to affect the behaviour of the FRP composites when matrix failure dominates the behaviour. The improvement in the mechanical response with the addition of low contents of MWCNTs would benefit many industrial and military applications such as strengthening structures using FRP composites, composite pipelines, aircrafts, and armoured vehicles.

  18. Homogenization of long fiber reinforced composites including fiber bending effects

    Poulios, Konstantinos; Niordson, Christian F.


    This paper presents a homogenization method, which accounts for intrinsic size effects related to the fiber diameter in long fiber reinforced composite materials with two independent constitutive models for the matrix and fiber materials. A new choice of internal kinematic variables allows to maintain the kinematics of the two material phases independent from the assumed constitutive models, so that stress-deformation relationships, can be expressed in the framework of hyper-elasticity and hyper-elastoplasticity for the fiber and the matrix materials respectively. The bending stiffness of the reinforcing fibers is captured by higher order strain terms, resulting in an accurate representation of the micro-mechanical behavior of the composite. Numerical examples show that the accuracy of the proposed model is very close to a non-homogenized finite-element model with an explicit discretization of the matrix and the fibers.

  19. Effect of Moisture Absorption Behavior on Mechanical Properties of Basalt Fibre Reinforced Polymer Matrix Composites

    Amuthakkannan Pandian; Manikandan Vairavan; Winowlin Jappes Jebbas Thangaiah; Marimuthu Uthayakumar


    The study of mechanical properties of fibre reinforced polymeric materials under different environmental conditions is much important. This is because materials with superior ageing resistance can be satisfactorily durable. Moisture effects in fibre reinforced plastic composites have been widely studied. Basalt fibre reinforced unsaturated polyester resin composites were subjected to water immersion tests using both sea and normal water in order to study the effects of water absorption behavi...

  20. Method of producing particulate-reinforced composites and composites produced thereby

    Han, Qingyou; Liu, Zhiwei


    A process for producing particle-reinforced composite materials through utilization of an in situ reaction to produce a uniform dispersion of a fine particulate reinforcement phase. The process includes forming a melt of a first material, and then introducing particles of a second material into the melt and subjecting the melt to high-intensity acoustic vibration. A chemical reaction initiates between the first and second materials to produce reaction products in the melt. The reaction products comprise a solid particulate phase, and the high-intensity acoustic vibration fragments and/or separates the reaction products into solid particles that are dispersed in the melt and are smaller than the particles of the second material. Also encompassed are particle-reinforced composite materials produced by such a process.

  1. Method of producing particulate-reinforced composites and composites produced thereby

    Han, Qingyou; Liu, Zhiwei


    A process for producing particle-reinforced composite materials through utilization of an in situ reaction to produce a uniform dispersion of a fine particulate reinforcement phase. The process includes forming a melt of a first material, and then introducing particles of a second material into the melt and subjecting the melt to high-intensity acoustic vibration. A chemical reaction initiates between the first and second materials to produce reaction products in the melt. The reaction products comprise a solid particulate phase, and the high-intensity acoustic vibration fragments and/or separates the reaction products into solid particles that are dispersed in the melt and are smaller than the particles of the second material. Also encompassed are particle-reinforced composite materials produced by such a process.

  2. glass fabric reinforced epoxy composite


    and steam turbine blades, gears of locomotives, conveyer belts, pump impellers in mineral slurry processing, where the components .... Care was taken to avoid formation of air bubbles during pouring. Pressure .... Materials and Design, Vol.

  3. Properties of glass/carbon fiber reinforced epoxy hybrid polymer composites

    Patel, R. H.; Sevkani, V. R.; Patel, B. R.; Patel, V. B.


    Composite Materials are well known for their tailor-made properties. For the fabrication of composites different types of reinforcements are used for different applications. Sometimes for a particular application, one type of reinforcement may not fulfill the requirements. Therefore, more than one type of reinforcements may be used. Thus, the idea of hybrid composites arises. Hybrid composites are made by joining two or more different reinforcements with suitable matrix system. It helps to improve the properties of composite materials. In the present work glass/carbon fiber reinforcement have been used with a matrix triglycidyl ether of tris(m-hydroxy phenyl) phosphate epoxy resin using amine curing agent. Different physical and mechanical properties of the glass, carbon and glass/carbon fiber reinforced polymeric systems have been found out.

  4. Carbon nanotube reinforced hybrid composites: Computational modeling of environmental fatigue and usability for wind blades

    Dai, Gaoming; Mishnaevsky, Leon


    The potential of advanced carbon/glass hybrid reinforced composites with secondary carbon nanotube reinforcement for wind energy applications is investigated here with the use of computational experiments. Fatigue behavior of hybrid as well as glass and carbon fiber reinforced composites...... with the secondary CNT reinforcements (especially, aligned tubes) present superior fatigue performances than those without reinforcements, also under combined environmental and cyclic mechanical loading. This effect is stronger for carbon composites, than for hybrid and glass composites....... automatically using the Python based code. 3D computational studies of environment and fatigue analyses of multiscale composites with secondary nano-scale reinforcement in different material phases and different CNTs arrangements are carried out systematically in this paper. It was demonstrated that composites...

  5. Sisal fibre pull-out behaviour as a guide to matrix selection for the production of sisal fibre reinforced cement matrix composites

    Mapiravana, Joe


    Full Text Available Natural fibre reinforced cement composites are promising potential materials for use in panelised construction. The structural properties of these composite materials are yet to be fully understood. As the role of the natural fibre is to reinforce...

  6. Polypropylene matrix composites reinforced with coconut fibers

    Maria Virginia Gelfuso


    Full Text Available Polypropylene matrix composites reinforced with treated coconut fibers were produced. Fibers chemically treated (alkalization-CCUV samples or mechanically treated (ultrasonic shockwave-CMUV samples were dried using UV radiation. The goal was to combine low cost and eco-friendly treatments to improve fiber-matrix adhesion. Composite samples containing up to 20 vol. (% of untreated and treated coconut fibers were taken from boxes fabricated by injection molding. Water absorption and mechanical properties were investigated according to ASTM D570-98 and ASTM D638-03, respectively. Electrical characterizations were carried out to identify applications of these composites in the electrical sector. NBR 10296-Electrical Tracking Standard (specific to industry applications and conductivity measurements were obtained applying 5 kV DC to the samples. CMUV samples containing 5 vol. (% fiber presented superior tensile strength values (σ~28 MPa compared to the untreated fibers composite (σ~22 MPa or alkali treatment (σ~24 MPa. However, CMUV composites containing 10 vol. (% fiber presented best results for the electrical tracking test and electrical resistivity (3 × 10(7 Ω.m. The results suggest that composites reinforced with mechanically treated coconut fibers are suitable for electrical applications.

  7. Composite Reinforcement using Boron Nitride Nanotubes


    Final 3. DATES COVERED (From - To) 11-Mar-2013 to 10-Mar-2014 4. TITLE AND SUBTITLE Composite Reinforcement using Boron Nitride Nanotubes...AVAILABILITY STATEMENT Approved for public release. 13. SUPPLEMENTARY NOTES 14. ABSTRACT Boron nitride nanotubes have been proposed as a...and titanium (Ti) metal clusters with boron nitride nanotubes (BNNT). First-principles density-functional theory plus dispersion (DFT-D) calculations

  8. Basalt fiber reinforced polymer composites: Processing and properties

    Liu, Qiang

    A high efficiency rig was designed and built for in-plane permeability measurement of fabric materials. A new data derivation procedure to acquire the flow fluid pattern in the experiment was developed. The measurement results of the in-plane permeability for basalt twill 31 fabric material showed that a high correlation exists between the two principal permeability values for this fabric at 35% fiber volume fraction. This may be the most important scientific contribution made in this thesis. The results from radial measurements corresponded quite well with those from Unidirectional (UD) measurements, which is a well-established technique. No significant differences in mechanical properties were found between basalt fabric reinforced polymer composites and glass composites reinforced by a fabric of similar weave pattern. Aging results indicate that the interfacial region in basalt composites may be more vulnerable to environmental damage than that in glass composites. However, the basalt/epoxy interface may have been more durable than the glass/epoxy interface in tension-tension fatigue because the basalt composites have significantly longer fatigue life. In this thesis, chapter I reviews the literature on fiber reinforced polymer composites, with concentration on permeability measurement, mechanical properties and durability. Chapter II discusses the design of the new rig for in-plane permeability measurement, the new derivation procedure for monitoring of the fluid flow pattern, and the permeability measurement results. Chapter III compares the mechanical properties and durability between basalt fiber and glass fiber reinforced polymer composites. Lastly, chapter IV gives some suggestions and recommendations for future work.

  9. Development of Textile Reinforced Composites for Aircraft Structures

    Dexter, H. Benson


    NASA has been a leader in development of composite materials for aircraft applications during the past 25 years. In the early 1980's NASA and others conducted research to improve damage tolerance of composite structures through the use of toughened resins but these resins were not cost-effective. The aircraft industry wanted affordable, robust structures that could withstand the rigors of flight service with minimal damage. The cost and damage tolerance barriers of conventional laminated composites led NASA to focus on new concepts in composites which would incorporate the automated manufacturing methods of the textiles industry and which would incorporate through-the-thickness reinforcements. The NASA Advanced Composites Technology (ACT) Program provided the resources to extensively investigate the application of textile processes to next generation aircraft wing and fuselage structures. This paper discusses advanced textile material forms that have been developed, innovative machine concepts and key technology advancements required for future application of textile reinforced composites in commercial transport aircraft. Multiaxial warp knitting, triaxial braiding and through-the-thickness stitching are the three textile processes that have surfaced as the most promising for further development. Textile reinforced composite structural elements that have been developed in the NASA ACT Program are discussed. Included are braided fuselage frames and window-belt reinforcements, woven/stitched lower fuselage side panels, stitched multiaxial warp knit wing skins, and braided wing stiffeners. In addition, low-cost processing concepts such as resin transfer molding (RTM), resin film infusion (RFI), and vacuum-assisted resin transfer molding (VARTM) are discussed. Process modeling concepts to predict resin flow and cure in textile preforms are also discussed.


    Laurent Bizet


    Full Text Available The microstructure of a unidirectional glass-fiber composite material is described seeking especially for the influence of the stitching perpendicular to the reinforcement. Serial cuts are performed through the composite and the microstructure is quantified using global parameters and linear morphological analysis. A key result is that the stitching induces variations in fibers spacing within the yarns and in the matrix volume between the yarns. This can affect noticeably the flow of the resin during the manufacturing process and also the mechanical properties of the composite.

  11. Non-Catalytic Self Healing Composite Material Solution Project

    National Aeronautics and Space Administration — Fiber reinforce polymer (FRP) composite materials are seeing increasing use in the construction of a wide variety of aerospace structures. However, uncertainties...

  12. Wedge Splitting Test and Fracture Energy on Particulate Reinforced Composites

    Na, Seong Hyeon; Kim, Jae Hoon; Choi, Hoon Seok [Chungnam National Univ., Daejeon (Korea, Republic of); Park, Jae Beom; Kim, Shin Hoe; Jung, Gyoo Dong [Agency for Defense Developmen, Daejeon (Korea, Republic of)


    The effect of temperature on the fracture energy, crack propagation, and crack tip opening displacement(CTOD) was determined for particulate reinforced composites using the wedge splitting test. The materials that were used consisted of a polymer binder, an oxidizing agent, and aluminum particles. The test rate of the wedge splitting specimen was 50 mm/min, the temperature conditions were 50℃, room temperature, -40℃, and -60℃. The fracture energy, calculated from splitting load-crack mouth opening displacement(CMOD) curves, increased with decreasing temperature from 50℃ to -40℃. In addition, the strength of the particulate reinforced composites increased sharply at -60℃, and the composites evidenced brittle fracture due to the glass transition temperature. The strain fields near the crack tip were analyzed using digital image correlation.

  13. Life Cycle Assessment of Biobased Fibre-Reinforced Polymer Composites (Levenscyclusanalyse van biogebaseerde, vezelversterkte polymeercomposieten)

    Deng, Yelin


    Today, global environmental issues, such as global warming and fossil depletion, drive a paradigm shift in material applications from conventional fossil sources to renewable sources. Following this trend, the topic of this thesis is to analyse the use of biobased resources for fibre reinforced composite fabrication. Currently the most widely used fibre reinforced composites are composed of glass fibre reinforcements and polymeric matrices. In this thesis, the biobased alternative, i.e. flax ...


    Nicolae ȚĂRANU


    Full Text Available The results of a complex research and development program relating to the use of fiber reinforced polymeric composite strengthening solutions carried out at the Faculty of Civil Engineering and Building Services Iasi, are presented in this paper. The program has included the conceiving of the structural rehabilitation systems, the detailing and experimental testing of some solutions applied to reinforced concrete beams, slabs and columns (with circular and square cross-section. An efficient use of the component materials to improve the structural performance of the studied reinforced concrete element has been the main target of the research program. The main benefits resulted from the research program refer to the increase of the load capacities, the improvement of the structural response of all strengthened elements and a better control of the failure modes.

  15. Development of Glass/Jute Fibers Reinforced Polyester Composite

    Amit Bindal


    Full Text Available Composites play significant role as engineering material and their use has been increasing day by day due to their specific properties such as high strength to weight ratios, high modulus to weight ratio, corrosion resistance, and wear resistance. In present work, an attempt is made to hybridize the material using synthetic (glass as well as natural fibres (chemically treated jute, such that to reduce the overall use of synthetic reinforcement, to reduce the overall cost, and to enhance the mechanical properties. All composite specimens with different weight percentages of fibres were manufactured using hand lay-up process and testing was done by using ASTM standards. Experimental results revealed that hybridization of composite with natural and synthetic fibres shows enhanced tensile strength, flexural strength, and impact strength. The content of natural reinforcement was found to be in the range of 25–33.3% for best results. The effect of treated jute on flexural properties was more than that on tensile properties, which was due to greater stiffness of jute fibers. Chemical treatment of jute fibers lowers the water absorption and results were comparable to glass fiber reinforced polyester composites. The addition of jute also reduced the overall cost by 22.18%.

  16. Mechanical interaction of Engineered Cementitious Composite (ECC) reinforced with Fiber Reinforced Polymer (FRP) rebar in tensile loading

    Lárusson, Lárus Helgi; Fischer, Gregor; Jönsson, Jeppe


    This paper introduces a preliminary study of the composite interaction of Engineered Cementitious Composite (ECC), reinforced with Glass Fiber Reinforced Polymer (GFRP) rebar. The main topic of this paper will focus on the interaction of the two materials (ECC and GFRP) during axial loading......, particularly in post cracking phase of the concrete matrix. The experimental program carried out in this study examined composite behavior under monotonic and cyclic loading of the specimens in the elastic and inelastic deformation phases. The stiffness development of the composite during loading was evaluated...

  17. Analysis/design of strip reinforced random composites (strip hybrids)

    Chamis, C. C.; Sinclair, J. H.


    Advanced analysis methods and composite mechanics were applied to a strip-reinforced random composite square panel with fixed ends to illustrate the use of these methods for the a priori assessment of the composite panel when subjected to complex loading conditions. The panel was assumed to be of E-glass random composite. The strips were assumed to be of three advanced unidirectional composites to cover a range of low, intermediate, and high modulus stiffness. The panels were assumed to be subjected to complex loadings to assess their adequacy as load-carrying members in auto body, aircraft engine nacelle and windmill blade applications. The results show that strip hybrid panels can be several times more structurally efficient than the random composite base materials. Some of the results are presented in graphical form and procedures are described for use of these graphs as guides for preliminary design of strip hybrids.

  18. Analysis/design of strip reinforced random composites /strip hybrids/

    Chamis, C. C.; Sinclair, J. H.


    Results are described which were obtained by applying advanced analysis methods and composite mechanics to a strip-reinforced random composite square panel with fixed ends. This was done in order to illustrate the use of these methods for the apriori assessment of the composite panel when subjected to complex loading conditions. The panel was assumed to be of E-Glass/Random Composite. The strips were assumed to be of three advanced unidirectional composites to cover a range of low, intermediate, and high modulus stiffness. The panels were assumed to be subjected to complex loadings to assess their adequacy as load-carrying members in auto body, aircraft engine nacelle, and windmill blade applications. The results show that strip hybrid panels can be several times more structurally efficient than the random composite base materials. Some of the results are presented in graphical form and procedures are described for use of these graphs as guides for preliminary design of strip hybrids.

  19. Tensile Strength of Natural Fiber Reinforced Polyester Composite

    Ismail, Al Emran; Awang, Muhd. Khairudin; Sa'at, Mohd Hisham


    Nowadays, increasing awareness of replacing synthetic fiber such as glass fiber has emerged due to environmental problems and pollutions. Automotive manufacturers also seek new material especially biodegradable material to be non-load bearing application parts. This present work discussed on the effect of silane treatment on coir fiber reinforced composites. From the results of tensile tests, fibers treated with silane have attained maximum material stiffness. However, to achieve maximum ultimate tensile strength and strain at failure performances, untreated fibers work very well through fiber bridging and internal friction between fiber and polymeric matrix. Scanning electron microscope (SEM) observations have coincided with these results.

  20. Novel dental composites reinforced with zirconia-silica ceramic nanofibers.

    Guo, Guangqing; Fan, Yuwei; Zhang, Jian-Feng; Hagan, Joseph L; Xu, Xiaoming


    To fabricate and characterize dental composites reinforced with various amounts of zirconia-silica (ZS) or zirconia-yttria-silica (ZYS) ceramic nanofibers. Control composites (70 wt% glass particle filler, no nanofibers) and experimental composites (2.5, 5.0, and 7.5 wt% ZS or ZYS nanofibers replacing glass particle filler) were prepared by blending 29 wt% dental resin monomers, 70 wt% filler, and 1.0 wt% initiator, and polymerized by either heat or dental curing light. Flexural strength (FS), flexural modulus (FM), energy at break (EAB), and fracture toughness (FT) were tested after the specimens were stored in 37°C deionized water for 24h, 3 months, or 6 months. Degree of conversion (DC) of monomers in composites was measured using Fourier transformed near-infrared (FT-NIR) spectroscopy. Fractured surfaces were observed by field-emission scanning electron microscope (FE-SEM). The data were analyzed using ANOVA with Tukey's Honestly Significant Differences test used for post hoc analysis. Reinforcement of dental composites with ZS or ZYS nanofibers (2.5% or 5.0%) can significantly increase the FS, FM and EAB of dental composites over the control. Further increase the content of ZS nanofiber (7.5%), however, decreases these properties (although they are still higher than those of the control). Addition of nanofibers did not decrease the long-term mechanical properties of these composites. All ZS reinforced composites (containing 2.5%, 5.0% and 7.5% ZS nanofibers) exhibit significantly higher fracture toughness than the control. The DC of the composites decreases with ZS nanofiber content. Incorporation of ceramic nanofibers in dental composites can significantly improve their mechanical properties and fracture toughness and thus may extend their service life. Copyright © 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  1. Compressive Failure of Fibre Reinforced Materials

    Jensen, Henrik Myhre


    Compressive failure of uni-directional fibre composites by the kink band mechanism is analysed taking into account effects of residual stresses. Two criteria for determining the strength of the composite material have been investigated: Kink band formation at a bifurcation stress in a composite...

  2. Microscopic mechanism of reinforcement and conductivity in polymer nanocomposite materials

    Chang, Tae-Eun

    Modification of polymers by adding various nano-particles is an important method to obtain effective enhancement of materials properties. Within this class of materials, carbon nanotubes (CNT) are among the most studied materials for polymer reinforcement due to their extraordinary mechanical properties, superior thermal and electronic properties, and high aspect ratio. However, to unlock the potential of CNTs for applications, CNTs must be well dispersed in a polymer matrix and the microscopic mechanism of polymer reinforcement by CNTs must be understood. In this study, single-wall carbon nanotube (SWNT) composites with polypropylene (PP)-SWNT and polystyrene (PS)-SWNT were prepared and analyzed. Microscopic study of the mechanism of reinforcement and conductivity by SWNT included Raman spectroscopy, wide-angle X-ray diffraction (WAXD) and dielectric measurement. For PP-SWNT composites, tensile tests show a three times increase in the Young's modulus with addition of only 1 wt% SWNT, and much diminished increase of modulus with further increase in SWNT concentration. For PS-SWNT composites, well-dispersed SWNT/PS composite has been produced, using initial annealing of SWNT and optimum sonication conditions. The studies on the tangential mode in the Raman spectra and TEM indicated well-dispersed SWNTs in a PS matrix. We show that conductivity appears in composites already at very low concentrations, hinting at the formation of a 'percolative' network even below 0.5% of SWNT. The Raman studies for both composites show good transfer of the applied stress from the polymer matrices to SWNTs. However, no significant improvement of mechanical property is observed for PS-SWNT composites. The reason for only a slight increase of mechanical property remains unknown.

  3. Carbon nanotube reinforced hybrid composites: Computational modeling of environmental fatigue and usability for wind blades

    Dai, Gaoming; Mishnaevsky, Leon


    The potential of advanced carbon/glass hybrid reinforced composites with secondary carbon nanotube reinforcement for wind energy applications is investigated here with the use of computational experiments. Fatigue behavior of hybrid as well as glass and carbon fiber reinforced composites...... with and without secondary CNT reinforcement is simulated using multiscale 3D unit cells. The materials behavior under both mechanical cyclic loading and combined mechanical and environmental loading (with phase properties degraded due to the moisture effects) is studied. The multiscale unit cells are generated...... with the secondary CNT reinforcements (especially, aligned tubes) present superior fatigue performances than those without reinforcements, also under combined environmental and cyclic mechanical loading. This effect is stronger for carbon composites, than for hybrid and glass composites....

  4. Mechanical analyses of pipeline repair and reinforcement with use of composite functionally graded materials; Analise mecanica de reforco de dutos submarinos com materiais compositos com gradacao funcional

    Queiroz, Marcos S.M. [Sondotecnica Engenharia de Solos S.A., Rio de Janeiro, RJ (Brazil); Roehl, Deane de Mesquita [Pontificia Universidade Catolica do Rio de Janeiro (PUC-Rio), RJ (Brazil)


    This work presents a methodology for design of stiffener sleeve constituted by functionally graded composite materials in offshore pipelines located in extreme-deep waters, where high mechanical resistance allied to an efficient system of thermal isolation is necessary, in view of the excellent thermomechanical behavior of composites. For the case of FGMs, due to continuous variation in its featuring, is necessary to employ an adapted model, based on a model typically adopted for conventional composites (Rule of Mixture), as the model idealized by Tamura, Tomato e Ozawa, the TTO model. In this report, the influence of geometric and materials parameters in mechanical behavior of pipelines under propagating collapse is analyzed. (author)

  5. Starch composites reinforced by bamboo cellulosic crystals.

    Liu, Dagang; Zhong, Tuhua; Chang, Peter R; Li, Kaifu; Wu, Qinglin


    Using a method of combined HNO(3)-KClO(3) treatment and sulfuric acid hydrolysis, bamboo cellulose crystals (BCCs) were prepared and used to reinforce glycerol plasticized starch. The structure and morphology of BCCs were investigated using X-ray diffraction, electron microscopy, and solid-state (13)C NMR. Results showed that BCCs were of typical cellulose I structure, and the morphology was dependent on its concentration in the suspension. BCC of 50-100 nm were assembled into leaf nervations at low concentration (i.e. 0.1 wt.% of solids), but congregated into a micro-sized "flower" geometry at high concentration (i.e. 10.0 wt.% of solids). Tensile strength and Young's modulus of the starch/BCC composite films (SBC) were enhanced by the incorporation of the crystals due to reinforcement of BCCs and reduction of water uptake. BCCs at the optimal 8% loading level exhibited a higher reinforcing efficiency for plasticized starch plastic than any other loading level.

  6. Fracture morphology of carbon fiber reinforced plastic composite laminates

    Vinod Srinivasa


    Full Text Available Carbon fiber reinforced plastic (CFRP composites have been extensively used in fabrication of primary structures for aerospace, automobile and other engineering applications. With continuous and widespread use of these composites in several advanced technology, the frequency of failures is likely to increase. Therefore, to establish the reasons for failures, the fracture modes should be understood thoroughly and unambiguously. In this paper, CFRP composite have been tested in tension, compression and flexural loadings; and microscopic study with the aid of Scanning Electron Microscope (SEM has been performed on failed (fractured composite surfaces to identify the principle features of failure. Efforts have been made in correlating the fracture surface characteristics to the failure mode. The micro-mechanics analysis of failure serves as a useful guide in selecting constituent materials and designing composites from the failure behavior point of view. Also, the local failure initiation results obtained here has been reliably extended to global failure prediction.

  7. Fabrication of aluminum matrix composite reinforced with carbon nanotubes


    1.0 wt.% carbon nanotube (CNT) reinforced 2024A1 matrix composite was fabricated by cold isostatic press and subsequent hot extrusion techniques. The mechanical properties of the composite were measured by a tensile test. Meanwhile, the fracture surfaces were examined using field emission scanning electron microscopy. The experimental results show that CNTs are dispersed homogeneously in the composite and that the interfaces of the Al matrix and the CNT bond well. Although the tensile strength and the Young's modulus of the composite are enhanced markedly, the elongation does not decrease when compared with the matrix material fabricated under the same process. The reasons for the increments may be the extraordinary mechanical properties of CNTs, and the bridging and pulling-out role of CNTs in the Al matrix composite.

  8. Multi-Length Scale-Enriched Continuum-Level Material Model for Kevlar (registered trademark)-Fiber-Reinforced Polymer-Matrix Composites


    polymer matrix composite materials display quite complex deformation and failure behavior under ballistic/blast impact loading conditions. This complexity is generally attributed to a number of factors such as (a) hierarchical/multi-length scale architecture of the material microstructure; (b) nonlinear, rate-dependent and often pressure-sensitive mechanical response; and (c) the interplay of various intrinsic phenomena and processes such as fiber twisting, interfiber friction/sliding, etc. Material models currently employed in the computational engineering

  9. Coupled heating/forming optimization of knitted reinforced composites

    Pancrace, Johann

    The feasibility of knitted fabric reinforcement for highly flexible composites has been investigated for the thermoforming process. The composite sheets were made through compression molding before being shaped. We used thermoplastic elastomers as matrices: Thermoplastic Elastomers and Thermoplastic Olefins. The knit reinforcement was provided by jersey knitted fabrics of polyester fibers. We first introduced the fundamentals involved in the study. The manufacturing is presented through compression molding and thermoforming. The latter is a two-step process: IR heating and plug/pressure assisted deformations. For the IR heating phase, several material properties have been characterized: the emissivity of matrices, absorption, reflection and transmission of radiations in the composite structure have been studied. We particularly paid attention to the reflection on the composite surfaces. The non-reflected or useful radiations leading to the heating are quantified and simulated for three emitter-composite configurations. It has been found that the emitter temperatures and the angle of incidence have significant roles in the IR heating phase. Thermal properties such as calorific capacity and thermal conductivity of the composites were also presented. Thermograms were carried out with an IR camera. Equipment and Thermogram acquisitions were both presented. Optimization of emitters was performed for a three emitter system. The objective function method has been illustrated. Regarding mechanical purposes, the characterizations of the matrices, reinforcements and flexible composites have been carried out. The studied loadings were uniaxial traction, pure shear and biaxial inflation. For the uniaxial extension, both the reinforcement and the composite were found highly anisotropic regarding the orientation of the loading toward the coursewise of the fabric. The resulting strains and stresses to rupture are also found anisotropic. However, for pure shear loading we observed

  10. Mechanical properties of natural fibre reinforced polymer composites

    A S Singha; Vijay Kumar Thakur


    During the last few years, natural fibres have received much more attention than ever before from the research community all over the world. These natural fibres offer a number of advantages over traditional synthetic fibres. In the present communication, a study on the synthesis and mechanical properties of new series of green composites involving Hibiscus sabdariffa fibre as a reinforcing material in urea–formaldehyde (UF) resin based polymer matrix has been reported. Static mechanical properties of randomly oriented intimately mixed Hibiscus sabdariffa fibre reinforced polymer composites such as tensile, compressive and wear properties were investigated as a function of fibre loading. Initially urea–formaldehyde resin prepared was subjected to evaluation of its optimum mechanical properties. Then reinforcing of the resin with Hibiscus sabdariffa fibre was accomplished in three different forms: particle size, short fibre and long fibre by employing optimized resin. Present work reveals that mechanical properties such as tensile strength, compressive strength and wear resistance etc of the urea–formaldehyde resin increases to considerable extent when reinforced with the fibre. Thermal (TGA/DTA/DTG) and morphological studies (SEM) of the resin and biocomposites have also been carried out.

  11. Impact–abrasion wear characteristics of in-situ VC-reinforced austenitic steel matrix composite

    Moghaddam, E.G., E-mail: [Department of Materials Science and Engineering, Sharif University of Technology, P.O. Box 11365-9466, Azadi Avenue, Tehran (Iran, Islamic Republic of); Karimzadeh, N. [Department of Materials Engineering, Islamic Azad University, Najafabad Branch, Isfahan (Iran, Islamic Republic of); Varahram, N.; Davami, P. [Department of Materials Science and Engineering, Sharif University of Technology, P.O. Box 11365-9466, Azadi Avenue, Tehran (Iran, Islamic Republic of)


    In this investigation, in-situ precipitation of vanadium carbides was employed to reinforce Fe–13Mn and Fe–13Mn–3W alloys by means of conventional melting and casting route. Microstructures were characterized by optical and scanning electron microscopy techniques. Mechanical properties of the materials were determined by hardness, impact toughness and tension tests. It was observed that tungsten improved the strength of the matrix and the reinforcements as well as tensile properties and work hardening rate of the VC-reinforced composite. Ball mill abrasion test was utilized to simulate impact–abrasion wear condition using two types of abrasive minerals. The results showed that the degree of benefit to be gained by the use of in-situ VC-reinforced composite materials depends strongly on crush strength of the abrasives. It was found that the studied particle-reinforced composite materials were only advantageous when the abrasives were relatively soft, providing low-stress abrasion condition.

  12. Enhancement of mechanical properties and interfacial adhesion by chemical odification of natural fibre reinforced polypropylene composites

    Erasmus, E


    Full Text Available Natural fibres are often used for reinforcing thermoplastics, like polypropylene, to manufacture composite materials exhibiting numerous advantages such as high mechanical properties, low density and biodegradability. The mechanical properties of a...

  13. Smart Behavior of Carbon Fiber Reinforced Cement-based Composite


    The electrical characteristics of cement-based material can be remarkably improved by the addition of short carbon fibers.Carbon fiber reinforced cement composite (CFRC) is an intrinsically smart material that can sense not only the stress andstrain, but also the temperature. In this paper, variations of electrical resistivity with external applied load, and relationof thermoelectric force and temperature were investigated. Test results indicated that the electrical signal is related to theincrease in the material volume resistivity during crack generation or propagation and the decrease in the resistivity duringcrack closure. Moreover, it was found that the fiber addition increased the linearity and reversibility of the Seebeck effect inthe cement-based materials. The change of electrical characteristics reflects large amount of information of inner damage andtemperature differential of composite, which can be used for stress-strain or thermal self-monitoring by embedding it in theconcrete structures.

  14. Strong and tough magnesium wire reinforced phosphate cement composites for load-bearing bone replacement.

    Krüger, Reinhard; Seitz, Jan-Marten; Ewald, Andrea; Bach, Friedrich-Wilhelm; Groll, Jürgen


    Calcium phosphate cements are brittle biomaterials of low bending strength. One promising approach to improve their mechanical properties is reinforcement with fibers. State of the art degradable reinforced composites contain fibers made of polymers, resorbable glass or whiskers of calcium minerals. We introduce a new class of composite that is reinforced with degradable magnesium alloy wires. Bending strength and ductility of the composites increased with aspect ratio and volume content of the reinforcements up to a maximal bending strength of 139±41MPa. Hybrid reinforcement with metal and polymer fibers (PLA) further improved the qualitative fracture behavior and gave indication of enhanced strength and ductility. Immersion tests of composites in SBF for seven weeks showed high corrosion stability of ZEK100 wires and slow degradation of the magnesium calcium phosphate cement by struvite dissolution. Finally, in vitro tests with the osteoblast-like cell line MG63 demonstrate cytocompatibility of the composite materials.

  15. Hybrid fiber and nanopowder reinforced composites for wind turbine blades

    Nikoloz M. Chikhradze


    Full Text Available The results of an investigation into the production of wind turbine blades manufactured using polymer composites reinforced by hybrid (carbon, basalt, glass fibers and strengthened by various nanopowders (oxides, carbides, borides are presented. The hybrid fiber-reinforced composites (HFRC were manufactured with prepreg technology by molding pre-saturated epoxy-strengthened matrix-reinforced fabric. Performance of the manufactured composites was estimated with values of the coefficient of operating condition (COC at a moderate and elevated temperature.

  16. Fly ash-reinforced thermoplastic starch composites

    Ma, X.F.; Yu, J.G.; Wang, N. [Tianjin University, Tianjin (China). School of Science


    As a by-product from the combustion of pulverized coal, fly ash was, respectively, used as the reinforcement for formamide and urea-plasticized thermoplastic starch (FUPTPS) and glycerol-plasticized thermoplastic starch (GPTPS). The introduction of fly ash improved tensile stress from 4.56 MPa to 7.78 MPa and Youngs modulus increased trebly from 26.8 MPa to 84.6 MPa for fly ash-reinforced FUPTPS (A-FUPTPS), while tensile stress increased from 4.55 MPa to 12.86 MPa and Youngs modulus increased six times from 76.4 MPa to 545 MPa for fly ash-reinforced GPTPS (A-GPTPS). X-ray diffractograms illustrated that fly ash destroyed the formation of starch ordered crystal structure, so both A-GPTPS and FUPTPS could resist the starch re-crystallization (retrogradation). Also fly ash improved water resistance of TPS. As shown by rheology, during the thermoplastic processing, the extruder screw speed effectively adjusted the flow behavior of A-FUPTPS, while the increasing of the processing temperature effectively ameliorated the flow behavior of A-GPTPS. However, superfluous ash contents (e.g., 20 wt%) worsened processing fluidity and resulted in the congregation of fly ash in FUPTPS matrix (tested by SEM) rather than in GPTPS matrix. This congregation decreased the mechanical properties and water resistance of the materials.

  17. Mullite-zirconium composites reinforced with ceramic fibres resistant to 1450 C; obtaining and properties

    Cerchez, L.; Constantinescu, S. [PROCEMA S.A. Bucharest - Research, Design and Experimental Production, Bucharest (Romania). Inst. for Construction and Construction Materials; Muntean, M. [Universitatea Politehnica, Bucharest (Romania). Faculty of Industrial Chemistry


    The purpose of this paper was the obtaining of some mullite-zirconium matrix composites, reinforced with ceramic fibres resistant to 1450 C. In order to establish the compositions, the raw materials were ground, depending on their nature, in many ways, and there were established the characteristics of ground resulted powders. On the obtained materials it was followed the evolution of the ceramic, mechanical and structural characteristics, depending on the heat treatment temperature, for various reinforcing coefficients. (orig.)

  18. Mechanical and tribological studies on nano particles reinforced hybrid aluminum based composite

    Muley Aniruddha V.


    Full Text Available Hybrid metal matrix composites are new class of materials due to their better mechanical properties which can be achieved through proper selection and combination of materials. The work reported in this paper is based on fabrication of hybrid composites by using nano particles as reinforcements. The hybrid composites were fabricated by reinforcing them with nano sized SiC and Al2O3 particles in order to study mechanical and tribological properties of these enhanced materials. A stir casting method was used to obtain hybrid composites. LM 6 aluminum alloy was used as a matrix material. The results shown increase in hardness as well as in ultimate tensile strength of the composites with small wt.% of nano-sized hybrid reinforcements. The composites produced also exhibit better tribological properties.

  19. Adhesive and Stress-Strain Properties of the Polymeric Layered Materials Reinforced by the Knitted Net

    Rakhimov Farhod Hushbakovich


    Full Text Available It is known that the textile materials (woven fabric and mesh used for reinforcing of various polymer films and coatings. This paper discusses reinforcement of thermoplastic polymers based on PE (Polyethylene and PVC (Polyvinyl Chloride with a knitted mesh weave loin. According by the research identified adhesion, strength and deformation properties of new polymer laminates. The production of such materials has been discussed in detail and performance of resultant composites material is analyzed and compared with other materials.

  20. Roughness and fibre reinforcement effect onto wettability of composite surfaces

    Bénard, Quentin; Fois, Magali; Grisel, Michel


    Wettability of glass/epoxy and carbon/epoxy composites materials has been determined via sessile drop technique. Good-Van Oss approach has been used to evaluate surface free energy parameters of smooth and rough surfaces. Results obtained point out the influence of fibre reinforcement on surface free energy of composite materials. In addition, the interest of surface treatment to increase surface roughness has been discussed in terms of wettability. To sum up, results obtained clearly demonstrate the necessity of considering properties of a given composite surface not only as a polymer but a fibre/polymer couple. The drawn conclusions are of great interest as it may have numerous consequences in applications such as adhesion.

  1. Influence of Carbon & Glass Fiber Reinforcements on Flexural Strength of Epoxy Matrix Polymer Hybrid Composites

    T.D. Jagannatha


    Full Text Available Hybrid composite materials are more attracted by the engineers because of their properties like stiffness and high specific strength which leads to the potential application in the area of aerospace, marine and automobile sectors. In the present investigation, the flexural strength and flexural modulus of carbon and glass fibers reinforced epoxy hybrid composites were studied. The vacuum bagging technique was adopted for the fabrication of polymer hybrid composite materials. The hardness, flexural strength and flexural modulus of the hybrid composites were determined as per ASTM standards. The hardness, flexural strength and flexural modulus were improved as the fiber reinforcement contents increased in the epoxy matrix material.

  2. Nano-composite materials

    Lee, Se-Hee; Tracy, C. Edwin; Pitts, J. Roland


    Nano-composite materials are disclosed. An exemplary method of producing a nano-composite material may comprise co-sputtering a transition metal and a refractory metal in a reactive atmosphere. The method may also comprise co-depositing a transition metal and a refractory metal composite structure on a substrate. The method may further comprise thermally annealing the deposited transition metal and refractory metal composite structure in a reactive atmosphere.

  3. On the Mechanical Properties of Hybrid Aluminium 7075 Matrix Composite Material Reinforced with SiC and TiC Produced by Powder Metallurgy Method

    S. Pradeep Devaneyan; R Ganesh; T. Senthilvelan


    Metal matrix composites are widely used in components of various components of industrial equipment because of their superior material properties like high stiffness to weight ratio and high impact strength and fracture toughness while compared to the conventional material. Due to the concepts of high strength to low weight ratio, Al 7075 was extensively applied in aircraft engine and wings. Even if Al 7075 has higher hardness, higher strength, excellent wear resistance, and high-temperature ...

  4. Puncture-Healing Thermoplastic Resin Carbon-Fiber-Reinforced Composites

    Gordon, Keith L. (Inventor); Siochi, Emilie J. (Inventor); Grimsley, Brian W. (Inventor); Cano, Roberto J. (Inventor); Czabaj, Michael W. (Inventor)


    A composite comprising a combination of a self-healing polymer matrix and a carbon fiber reinforcement is described. In one embodiment, the matrix is a polybutadiene graft copolymer matrix, such as polybutadiene graft copolymer comprising poly(butadiene)-graft-poly(methyl acrylate-co-acrylonitrile). A method of fabricating the composite is also described, comprising the steps of manufacturing a pre-impregnated unidirectional carbon fiber preform by wetting a plurality of carbon fibers with a solution, the solution comprising a self-healing polymer and a solvent, and curing the preform. A method of repairing a structure made from the composite of the invention is described. A novel prepreg material used to manufacture the composite of the invention is described.

  5. Chairside fabricated fiber-reinforced composite fixed partial denture

    Sufyan Garoushi


    Full Text Available The advances in the materials and techniques for adhesive dentistry have allowed the development of non-invasive or minimally invasive approaches for replacing a missing tooth in those clinical situations when conservation of adjacent teeth is needed. Good mechanical and cosmetic/aesthetic properties of fiber-reinforced composite (FRC, with good bonding properties with composite resin cement and veneering composite are needed in FRC devices. Some recent studies have shown that adhesives of composite resins and luting cements allow diffusion of the adhesives to the FRC framework of the bridges. By this so-called interdiffusion bonding is formed [1]. FRC bridges can be made in dental laboratories or chairside. This article describes a clinical case of chairside (directly made FRC Bridge, which was used according to the principles of minimal invasive approach. Treatment was performed by Professor Vallittu from the University of Turku, Finland.

  6. Electron processing of fibre-reinforced advanced composites

    Singh, Ajit; Saunders, Chris B.; Barnard, John W.; Lopata, Vince J.; Kremers, Walter; McDougall, Tom E.; Chung, Minda; Tateishi, Miyoko


    Advanced composites, such as carbon-fibre-reinforced epoxies, are used in the aircraft, aerospace, sporting goods, and transportation industries. Though thermal curing is the dominant industrial process for advanced composites, electron curing of similar composites containing acrylated epoxy matrices has been demonstrated by our work. The main attraction of electron processing technology over thermal technology is the advantages it offers which include ambient temperature curing, reduced curing times, reduced volatile emissions, better material handling, and reduced costs. Electron curing technology allows for the curing of many types of products, such as complex shaped, those containing different types of fibres, and up to 15 cm thick. Our work has been done principally with the AECL's 10 MeV, 1 kW electron accelerator; we have also done some comparative work with an AECL Gammacell 220. In this paper we briefly review our work on the various aspects of electron curing of advanced composites and their properties.

  7. Anomaly detection of microstructural defects in continuous fiber reinforced composites

    Bricker, Stephen; Simmons, J. P.; Przybyla, Craig; Hardie, Russell


    Ceramic matrix composites (CMC) with continuous fiber reinforcements have the potential to enable the next generation of high speed hypersonic vehicles and/or significant improvements in gas turbine engine performance due to their exhibited toughness when subjected to high mechanical loads at extreme temperatures (2200F+). Reinforced fiber composites (RFC) provide increased fracture toughness, crack growth resistance, and strength, though little is known about how stochastic variation and imperfections in the material effect material properties. In this work, tools are developed for quantifying anomalies within the microstructure at several scales. The detection and characterization of anomalous microstructure is a critical step in linking production techniques to properties, as well as in accurate material simulation and property prediction for the integrated computation materials engineering (ICME) of RFC based components. It is desired to find statistical outliers for any number of material characteristics such as fibers, fiber coatings, and pores. Here, fiber orientation, or `velocity', and `velocity' gradient are developed and examined for anomalous behavior. Categorizing anomalous behavior in the CMC is approached by multivariate Gaussian mixture modeling. A Gaussian mixture is employed to estimate the probability density function (PDF) of the features in question, and anomalies are classified by their likelihood of belonging to the statistical normal behavior for that feature.

  8. Multifunctional materials and composites

    Seo, Dong-Kyun; Jeon, Ki-Wan


    Forming multifunctional materials and composites thereof includes contacting a first material having a plurality of oxygen-containing functional groups with a chalcogenide compound, and initiating a chemical reaction between the first material and the chalcogenide compound, thereby replacing oxygen in some of the oxygen-containing functional groups with chalcogen from the chalcogen-containing compound to yield a second material having chalcogen-containing functional groups and oxygen-containing functional groups. The first material is a carbonaceous material or a macromolecular material. A product including the second material is collected and may be processed further to yield a modified product or a composite.

  9. Asymptotic Analysis of Fiber-Reinforced Composites of Hexagonal Structure

    Kalamkarov, Alexander L.; Andrianov, Igor V.; Pacheco, Pedro M. C. L.; Savi, Marcelo A.; Starushenko, Galina A.


    The fiber-reinforced composite materials with periodic cylindrical inclusions of a circular cross-section arranged in a hexagonal array are analyzed. The governing analytical relations of the thermal conductivity problem for such composites are obtained using the asymptotic homogenization method. The lubrication theory is applied for the asymptotic solution of the unit cell problems in the cases of inclusions of large and close to limit diameters, and for inclusions with high conductivity. The lubrication method is further generalized to the cases of finite values of the physical properties of inclusions, as well as for the cases of medium-sized inclusions. The analytical formulas for the effective coefficient of thermal conductivity of the fiber-reinforced composite materials of a hexagonal structure are derived in the cases of small conductivity of inclusions, as well as in the cases of extremely low conductivity of inclusions. The three-phase composite model (TPhM) is applied for solving the unit cell problems in the cases of the inclusions with small diameters, and the asymptotic analysis of the obtained solutions is performed for inclusions of small sizes. The obtained results are analyzed and illustrated graphically, and the limits of their applicability are evaluated. They are compared with the known numerical and asymptotic data in some particular cases, and very good agreement is demonstrated.

  10. Evolution of the internal friction in SIC particle reinforced 8090 Al-Li metal matrix composite; Evolucion de la friccion interna del material compuesto de matriz Al-Li 8090 reforzado con particulas de SiC

    Gutierrez-Urrutia, I.; Gallego, I.; No, M. L.; San Juan, J. M.


    The present study has been undertaken to investigate the mechanisms of thermal stress relief at the range of temperatures below room temperature for the metal matrix composite Al-Li 8090/SiC. For this aim the experimental technique of internal friction has been used which has been showed up very effective. Several thermal cycles from 453 K to 100 K were used in order to measures the internal friction as well as the elastic modules of the material concluding that thermal stresses are relaxed by microplastic deformation around the reinforcements. It has been also related the variation in the elastic modules with the different levels of precipitation. (Author) 18 refs.

  11. Design aid for shear strengthening of reinforced concrete T-joints using carbon fiber reinforced plastic composites

    Gergely, Ioan

    The research presented in the present work focuses on the shear strengthening of beam column joints using carbon fiber composites, a material considered in seismic retrofit in recent years more than any other new material. These composites, or fiber reinforced polymers, offer huge advantages over structural steel reinforced concrete or timber. A few of these advantages are the superior resistance to corrosion, high stiffness to weight and strength to weight ratios, and the ability to control the material's behavior by selecting the orientation of the fibers. The design and field application research on reinforced concrete cap beam-column joints includes analytical investigations using pushover analysis; design of carbon fiber layout, experimental tests and field applications. Several beam column joints have been tested recently with design variables as the type of composite system, fiber orientation and the width of carbon fiber sheets. The surface preparation has been found to be critical for the bond between concrete and composite material, which is the most important factor in joint shear strengthening. The final goal of this thesis is to develop design aids for retrofitting reinforced concrete beam column joints. Two bridge bents were tested on the Interstate-15 corridor. One bent was tested in the as-is condition. Carbon fiber reinforced plastic composite sheets were used to externally reinforce the second bridge bent. By applying the composite, the displacement ductility has been doubled, and the bent overall lateral load capacity has been increased as well. The finite element model (using DRAIN-2DX) was calibrated to model the actual stiffness of the supports. The results were similar to the experimental findings.

  12. Multifunctional Composite Materials Project

    National Aeronautics and Space Administration — Polymeric composite materials that are currently utilized in aircraft structures are susceptible to significant damage from lightning strikes. Enhanced electrical...

  13. Hygrothermal effects on fiber reinforced polyphenylene sulphide composites : humidity uptake and temperature influence on mechanical properties of glass and carbon fiber reinforced polyphenylene sulphide composites

    Suárez Cabrera, Emmanuel


    In the ever-continuing quest for greener and cheaper aerospace materials, the Durability Group, part of the Design and Production of Composite Structures Department at the faculty of Aerospace Engineering of the Delft University of Technology is focusing on the use of new thermoplastic composites for aerospace structures. Currently the introduction of Nylon composites in the aerospace industry is being investigated. Nylon as a thermoplastic matrix for fibre reinforced composites can be bought...

  14. Nondestructive testing of externally reinforced structures for seismic retrofitting using flax fiber reinforced polymer (FFRP) composites

    Ibarra-Castanedo, C.; Sfarra, S.; Paoletti, D.; Bendada, A.; Maldague, X.


    Natural fibers constitute an interesting alternative to synthetic fibers, e.g. glass and carbon, for the production of composites due to their environmental and economic advantages. The strength of natural fiber composites is on average lower compared to their synthetic counterparts. Nevertheless, natural fibers such as flax, among other bast fibers (jute, kenaf, ramie and hemp), are serious candidates for seismic retrofitting applications given that their mechanical properties are more suitable for dynamic loads. Strengthening of structures is performed by impregnating flax fiber reinforced polymers (FFRP) fabrics with epoxy resin and applying them to the component of interest, increasing in this way the load and deformation capacities of the building, while preserving its stiffness and dynamic properties. The reinforced areas are however prompt to debonding if the fabrics are not mounted properly. Nondestructive testing is therefore required to verify that the fabric is uniformly installed and that there are no air gaps or foreign materials that could instigate debonding. In this work, the use of active infrared thermography was investigated for the assessment of (1) a laboratory specimen reinforced with FFRP and containing several artificial defects; and (2) an actual FFRP retrofitted masonry wall in the Faculty of Engineering of the University of L'Aquila (Italy) that was seriously affected by the 2009 earthquake. Thermographic data was processed by advanced signal processing techniques, and post-processed by computing the watershed lines to locate suspected areas. Results coming from the academic specimen were compared to digital speckle photography and holographic interferometry images.

  15. Experimental Investigation and Analysis of Mechanical Properties of Palm fibre reinforced Epoxy composites and Sisal fibre reinforced Polyester composites

    B. Muthu Chozha Rajan


    Full Text Available The objective of this paper was investigated to evaluate tensile, flexural and Impact properties of Palm fibre reinforced Epoxy composites (PFRP and compared with Sisal fibre reinforced Polyester composites (SFRP. Untreated chopped Palmyra Palm fruit fibre was used as reinforcement in Epoxy resin matrix and chopped sisal fibre was used as reinforcement in Polyester resin matrix. The chopped palm fibrereinforced composite were prepared in volume fractions (Vf such as 10 %, 20 % and 30 % of specimens by using Epoxy and the chopped sisalfibre reinforced composite were prepared in volume fractions (Vf such as 10 %, 20 % and 30 % of specimens by using Polyester. The specimens are tested for their mechanical Properties strictly as per ASTM procedures. Static analysis is performed by FEA based software ANSYS R15 with design constraints as Equivalent stress, Shear stress and deflection.The experimental result and analysis shows that the fibre volume fraction increases the tensile, flexural, Impact strength and modulus of the fibre reinforced composites

  16. Material and Flexural Properties of Fiber-reinforced Rubber Concrete

    Helminger, Nicholas P.

    The purpose of this research is to determine the material properties of rubber concrete with the addition of fibers, and to determine optimal mixture dosages of rubber and fiber in concrete for structural applications. Fiber-reinforced concrete and rubberized concrete have been researched separately extensively, but this research intends to combine both rubber and fiber in a concrete matrix in order to create a composite material, fiber-reinforced rubber concrete (FRRC). Sustainability has long been important in engineering design, but much of the previous research performed on sustainable concrete does not result in a material that can be used for practical purposes. While still achieving a material that can be used for structural applications, economical considerations were given when choosing the proportions and types of constituents in the concrete mix. Concrete mixtures were designed, placed, and tested in accordance with common procedures and standards, with an emphasis on practicality. Properties that were investigated include compressive strength, tensile strength, modulus of elasticity, toughness, and ductility. The basis for determining the optimal concrete mixture is one that is economical, practical, and exhibits ductile properties with a significant strength. Results show that increasing percentages of rubber tend to decrease workability, unit weight, compressive strength, split tensile strength, and modulus of elasticity while the toughness is increased. The addition of steel needle fibers to rubber concrete increases unit weight, compressive strength, split tensile strength, modulus of elasticity, toughness, and ductility of the composite material.

  17. Reinforced pericardium as a hybrid material for cardiovascular applications.

    Bracaglia, Laura G; Yu, Li; Hibino, Narutoshi; Fisher, John P


    Pericardium-based cardiovascular devices are currently bound by a 10-year maximum lifetime due to detrimental calcification and degradation. The goal of this work is to develop a novel synthetic material to create a lasting replacement for malfunctioning or diseased tissue in the cardiovascular system. This study couples poly(propylene fumarate) (PPF) and a natural biomaterial together in an unprecedented hybrid composite and evaluates the composite versus the standard glutaraldehyde-treated tissue. The polymer reinforcement is hypothesized to provide initial physical protection from proteolytic enzymes and degradation, but leave the original collagen and elastin matrix unaltered. The calcification rate and durability of the hybrid material are evaluated in vitro and in an in vivo subdermal animal model. Results demonstrate that PPF is an effective support and leads to significantly less calcium deposition, important metrics when evaluating cardiovascular material. By avoiding chemical crosslinking of the tissue and associated side effects, PPF-reinforced pericardium as a biohybrid material offers a promising potential direction for further development in cardiovascular material alternatives. Eliminating the basis for the majority of cardiovascular prosthetic failures could revolutionize expectations for extent of cardiovascular repair.

  18. Calculation of the relative uniformity coefficient on the green composites reinforced with cotton and hemp fabric

    Baciu, Florin; Hadǎr, Anton; Sava, Mihaela; Marinel, Stǎnescu Marius; Bolcu, Dumitru


    In this paper it is studied the influence of discontinuities on elastic and mechanical properties of green composite materials (reinforced with fabric of cotton or hemp). In addition, it is studied the way variations of the volume f the reinforcement influences the elasticity modulus and the tensile strength for the studied composite materials. In order to appreciate the difference in properties between different areas of the composite material, and also the dimensions of the defective areas, we have introduced a relative uniformity coefficient with which the mechanical behavior of the studied composite is compared with a reference composite. To validate the theoretical results we have obtained we made some experiments, using green composites reinforced with fabric, with different imperfection introduced special by cutting the fabric.

  19. Self Healing Fibre-reinforced Polymer Composites: an Overview

    Bond, Ian P.; Trask, Richard S.; Williams, Hugo R.; Williams, Gareth J.

    Lightweight, high-strength, high-stiffness fibre-reinforced polymer composite materials are leading contenders as component materials to improve the efficiency and sustainability of many forms of transport. For example, their widespread use is critical to the success of advanced engineering applications, such as the Boeing 787 and Airbus A380. Such materials typically comprise complex architectures of fine fibrous reinforcement e.g. carbon or glass, dispersed within a bulk polymer matrix, e.g. epoxy. This can provide exceptionally strong, stiff, and lightweight materials which are inherently anisotropic, as the fibres are usually arranged at a multitude of predetermined angles within discrete stacked 2D layers. The direction orthogonal to the 2D layers is usually without reinforcement to avoid compromising in-plane performance, which results in a vulnerability to damage in the polymer matrix caused by out-of-plane loading, i.e. impact. Their inability to plastically deform leaves only energy absorption via damage creation. This damage often manifests itself internally within the material as intra-ply matrix cracks and inter-ply delaminations, and can thus be difficult to detect visually. Since relatively minor damage can lead to a significant reduction in strength, stiffness and stability, there has been some reticence by designers for their use in safety critical applications, and the adoption of a `no growth' approach (i.e. damage propagation from a defect constitutes failure) is now the mindset of the composites industry. This has led to excessively heavy components, shackling of innovative design, and a need for frequent inspection during service (Richardson 1996; Abrate 1998).

  20. Optimizing the delamination failure in bamboo fiber reinforced polyester composite

    N. Abilash


    Full Text Available Delamination is represented to be the most prevalent failure in composite structures. The use of composites in the manufacturing sector plays a very important role in the industry in general. Moreover these materials have unique characteristics when analyzed separately from constituents which are a part of them. In this paper, a partially ecological composite was made, using natural fibers as reinforcement (bamboo fiber, in the polyester resin matrix to form a composite, seeking to improve the mechanical behavior among its class of materials. The characteristics of a composite material are determined by how it behaves while machining, Drilling is the most predominant machining process because of its cost effectiveness when compared with other processes. Obviously delamination is the major problem that is focused by many researchers while selecting drilling as the machining process in polymeric composites. This research mainly emphasizes on the critical parameters by varying its speed, feed, and diameter of the cutting tool, their contribution to delamination was analyzed. Reduced delaminations were identified by varying the speed and feed rate.

  1. Fibrous and textile materials for composite applications

    Fangueiro, Raul


    This book focuses on the fibers and textiles used in composite materials. It presents both existing technologies currently used in commercial applications and the latest advanced research and developments. It also discusses the different fiber forms and architectures, such as short fibers, unidirectional tows, directionally oriented structures or advanced 2D- and 3D-textile structures that are used in composite materials. In addition, it examines various synthetic, natural and metallic fibers that are used to reinforce polymeric, cementitious and metallic matrices, as well as fiber properties, special functionalities, manufacturing processes, and composite processing and properties. Two entire chapters are dedicated to advanced nanofiber and nanotube reinforced composite materials. The book goes on to highlight different surface treatments and finishes that are applied to improve fiber/matrix interfaces and other essential composite properties. Although a great deal of information about fibers and textile str...

  2. Synthesis and Characterization of Short Saccaharum Cilliare Fibre Reinforced Polymer Composites

    A. S. Singha


    Full Text Available This paper deals with the synthesis of short Saccaharum Cilliare fibre (SC reinforced Urea-Formaldehyde (UF matrix based polymer composites. Present work reveals that mechanical properties such as: tensile strength, compressive strength, flexural strength and wear resistance of the UF matrix increase up to 30% fibre loading(in terms of weight and then decreases for higher loading when fibers are incorporated into the matrix polymer. Morphological and Thermal studies of the matrix, fibre and short fibre reinforced (SF-Rnf green composites have also been carried out. The results obtained emphasize the applications of these fibres, as potential reinforcing materials in bio based composites.

  3. Processing, structure and flexural strength of CNT and carbon fibre reinforced, epoxy-matrix hybrid composite

    K Chandra Shekar; M Sai Priya; P K Subramanian; Anil Kumar; B Anjaneya Prasad; N Eswara Prasad


    Advanced materials such as continuous fibre-reinforced polymer matrix composites offer significant enhancements in variety of properties, as compared to their bulk, monolithic counterparts. These properties include primarily the tensile stress, flexural stress and fracture parameters. However, till date, there are hardly any scientific studies reported on carbon fibre (Cf) and carbon nanotube (CNT) reinforced hybrid epoxy matrix composites (unidirectional). The present work is an attempt to bring out the flexural strength properties along with a detailed investigation in the synthesis of reinforced hybrid composite. In this present study, the importance of alignment of fibre is comprehensively evaluated and reported. The results obtained are discussed in terms of material characteristics, microstructure and mode of failure under flexural (3-point bend) loading. The study reveals the material exhibiting exceptionally high strength values and declaring itself as a material with high strength to weight ratio when compared to other competing polymer matrix composites (PMCs); as a novel structural material for aeronautical and aerospace applications.

  4. Reinforced cementitous composite with in situ shrinking microfibers

    Kim, Eric S.; Lee, Jason K.; Lee, Patrick C.; Huston, Dryver R.; Tan, Ting; Al-Ghamdi, Saleh


    This paper describes an innovative fiber reinforcement technology for cementitious composite structures that employs in situ shrinking microfibers to provide supplemental strength-enhancing compressive stresses. Reinforced concrete is one of the most commonly used structural materials in construction industry, primarily due to its cost, durability, ability to be easily fabricated into a variety of shapes on site, and locally abundant raw material availability almost everywhere. Unlike incumbent passive reinforcing microfiber technology, in situ shrinking microfibers that respond to an in situ stimulus such as heat, pH, or moisture variations can induce pre-compression to matrix and create additional resistance from external loads, creating stronger composite structures. In this paper, heat-activated-shrinking (HAS) microfibers made from polyolefin, and pH-activated-shrinking (pHAS) microfibers made from chitosan powder were used to study effects of shrinking microfiber reinforcing in concrete. Shrinking ratios and tensile strengths of both microfibers were measured. Cementitious specimens with active shrinking microfibers, passive non shrinking fibers, as well as control samples were made. Mechanical properties of the samples were compared with compression and three-point bending tests. The optimum microfiber weight percentages for HAS microfibers were 0.5 wt% in compression tests, and 1.0 wt% in three-point bending tests. For pHAS microfibers, the optimum weight percentages were 0.5 wt% in three-point bending tests. Compared to heat passive microfibers specimens, 45% increase in the maximum compression strengths, and 124% increase in the maximum bending strengths were achieved at the optimum weight percentages of HAS microfibers. In addition, with 0.5 wt% of pHAS microfibers, 145% increase in the maximum bending strengths of three-point bending tests resulted compared to pH passive microfibers specimens.

  5. Friction Material Composites Materials Perspective

    Sundarkrishnaa, K L


    Friction Material Composites is the first of the five volumes which strongly educates and updates engineers and other professionals in braking industries, research and test labs. It explains besides the formulation of design processes and its complete manufacturing input. This book gives an idea of mechanisms of friction and how to control them by designing .The book is  useful for designers  of automotive, rail and aero industries for designing the brake systems effectively with the integration of friction material composite design which is critical. It clearly  emphasizes the driving  safety and how serious designers should  select the design input. The significance of friction material component like brake pad or a liner as an integral part of the brake system of vehicles is explained. AFM pictures at nanolevel illustrate broadly the explanations given.

  6. Microstructure and mechanical behavior of metallic glass fiber-reinforced Al alloy matrix composites.

    Wang, Z; Georgarakis, K; Nakayama, K S; Li, Y; Tsarkov, A A; Xie, G; Dudina, D; Louzguine-Luzgin, D V; Yavari, A R


    Metallic glass-reinforced metal matrix composites are an emerging class of composite materials. The metallic nature and the high mechanical strength of the reinforcing phase offers unique possibilities for improving the engineering performance of composites. Understanding the structure at the amorphous/crystalline interfaces and the deformation behavior of these composites is of vital importance for their further development and potential application. In the present work, Zr-based metallic glass fibers have been introduced in Al7075 alloy (Al-Zn-Mg-Cu) matrices using spark plasma sintering (SPS) producing composites with low porosity. The addition of metallic glass reinforcements in the Al-based matrix significantly improves the mechanical behavior of the composites in compression. High-resolution TEM observations at the interface reveal the formation of a thin interdiffusion layer able to provide good bonding between the reinforcing phase and the Al-based matrix. The deformation behavior of the composites was studied, indicating that local plastic deformation occurred in the matrix near the glassy reinforcements followed by the initiation and propagation of cracks mainly through the matrix. The reinforcing phase is seen to inhibit the plastic deformation and retard the crack propagation. The findings offer new insights into the mechanical behavior of metal matrix composites reinforced with metallic glasses.

  7. Inorganic-whisker-reinforced polymer composites synthesis, properties and applications

    Sun, Qiuju


    Inorganic-Whisker-Reinforced Polymer Composites: Synthesis, Properties and Applications gives a comprehensive presentation of inorganic microcrystalline fibers, or whiskers, a polymer composite filler. It covers whisker synthesis, surface modification, applications for reinforcing polymer-matrix composites, and analysis of resulting filled polymer composites. It focuses on calcium carbonate whiskers as a primary case study, introducing surface treatment methods for calcium carbonate whiskers and factors that influence them.Along with calcium carbonate, the book discusses potassium titanate and

  8. Glass fibre reinforced cement based composite: fatigue and fracture parameters

    Seitl S.


    Full Text Available This paper introduces the basic fracture mechanics parameters of advanced building material – glass fibres reinforced cement based composite and its fracture and fatigue behaviour is investigated. To this aim three-point bend (3PB specimens with starting notch were prepared and tested under static (l–d diagram and cyclic loading (Paris law and Ẅöhler curve. To evaluate the results, the finite element method was used for estimation of the corresponding values of stress intensity factor for the 3PB specimen used. The results obtained are compared with literature data.

  9. Micromechanical analysis of interaction enersy for SMA reinforced composite

    ZHU YuPing; DUI GuanSuo; DUO Liu


    The energy of the interaction between the matrix and the inclusions in shape memory alloy (SMA) re-inforced composite is one of the most important and complicated parts in thermodynamic constitutive theory. In this paper, the interaction energy is derived based on the classical theory of micromechanics and the thermodynamic theory. The SMA composite is treated as three phases, namely the austenitic phase, the martensite phase and the matrix phase. The interaction among the three phases is analyzed in a way close to the fact. The present expression is used to calculate the interaction energy of a typical SMA composite with attentions paid to understand of the effects of the matrix material, the fiber ge-ometry, and the fiber/matrix volume ratio. It is shown that the method developed in this paper is credi-ble compared with the references. Some useful conclusions are obtained.

  10. Microstructure and Tensile Behaviour of B4C Reinforced ZA43 Alloy Composites

    Adaveesh, B.; Halesh, G. M.; Nagaral, Madeva; Mohan Kumar, T. S.


    The work is carried out to investigate and study the mechanical properties of B4C reinforced ZA43 alloy metal matrix composites. In the present work ZA43 alloy is taken as the base matrix and B4C particulates as reinforcement material to prepare metal matrix composites by stir casting method. For metal matrix composites the reinforcement material was varied from 0 to 6 wt.% in steps of 3 wt.%. For each composite, the reinforcement particulates were preheated to a temperature of 300°C and dispersed into a vortex of molten ZA43 alloy. The microstructural characterization was done using scanning electron microscope. Mechanical properties like hardness, ultimate tensile strength and yield strength were evaluated as per ASTM standards. Further, scanning electron microphotographs revealed that there was uniform distribution of B4C particulates in ZA43 alloy matrix. Hardness, ultimate tensile strength and yield strength increased as wt.% of B4C increased in the base matrix.

  11. Flexural analysis of palm fiber reinforced hybrid polymer matrix composite

    Venkatachalam, G.; Gautham Shankar, A.; Raghav, Dasarath; Santhosh Kiran, R.; Mahesh, Bhargav; Kumar, Krishna


    Uncertainty in availability of fossil fuels in the future and global warming increased the need for more environment friendly materials. In this work, an attempt is made to fabricate a hybrid polymer matrix composite. The blend is a mixture of General Purpose Resin and Cashew Nut Shell Liquid, a natural resin extracted from cashew plant. Palm fiber, which has high strength, is used as reinforcement material. The fiber is treated with alkali (NaOH) solution to increase its strength and adhesiveness. Parametric study of flexure strength is carried out by varying alkali concentration, duration of alkali treatment and fiber volume. Taguchi L9 Orthogonal array is followed in the design of experiments procedure for simplification. With the help of ANOVA technique, regression equations are obtained which gives the level of influence of each parameter on the flexure strength of the composite.

  12. Mechanical Properties of Composite Materials

    Mitsuhiro Okayasu


    Full Text Available An examination has been made of the mechanical and failure properties of several composite materials, such as a short and a long carbon fiber reinforced plastic (short- and long-CFRP and metal based composite material. The short CFRP materials were used for a recycled CFRP which fabricated by the following process: the CFRP, consisting of epoxy resin with carbon fiber, is injected to a rectangular plate cavity after mixing with acrylonitrile butadiene styrene resin with different weight fractions of CFRP. The fatigue and ultimate tensile strength (UTS increased with increasing CFRP content. These correlations, however, break down, especially for tensile strength, as the CFPR content becomes more than 70%. Influence of sample temperature on the bending strength of the long-CFRP was investigated, and it appears that the strength slightly decreases with increasing the temperature, due to the weakness in the matrix. Broken fiber and pull-out or debonding between the fiber and matrix were related to the main failure of the short- and long-CFRP samples. Mechanical properties of metal based composite materials have been also investigated, where fiber-like high hardness CuAl2 structure is formed in aluminum matrix. Excellent mechanical properties were obtained in this alloy, e.g., the higher strength and the higher ductility, compared tothe same alloy without the fiber-like structure. There are strong anisotropic effects on the mechanical properties due to the fiber-like metal composite in a soft Al based matrix.

  13. Fiber-Reinforced-Foam (FRF) Core Composite Sandwich Panel Concept for Advanced Composites Technologi


    Fiber-Reinforced-Foam (FRF) Core Composite Sandwich Panel Concept for Advanced Composites Technologies Project - Preliminary Manufacturing Demonstration Articles for Ares V Payload Shroud Barrel Acreage Structure

  14. Aluminum matrix composites reinforced with alumina nanoparticles

    Casati, Riccardo


    This book describes the latest efforts to develop aluminum nanocomposites with enhanced damping and mechanical properties and good workability. The nanocomposites exhibited high strength, improved damping behavior and good ductility, making them suitable for use as wires. Since the production of metal matrix nanocomposites by conventional melting processes is considered extremely problematic (because of the poor wettability of the nanoparticles), different powder metallurgy routes were investigated, including high-energy ball milling and unconventional compaction methods. Special attention was paid to the structural characterization at the micro- and nanoscale, as uniform nanoparticle dispersion in metal matrix is of prime importance. The aluminum nanocomposites displayed an ultrafine microstructure reinforced with alumina nanoparticles produced in situ or added ex situ. The physical, mechanical and functional characteristics of the materials produced were evaluated using different mechanical tests and micros...

  15. Adhesion analysis between metal supplies and composites materials reinforce with glass fiber; Analise de adesao antre materiais metalicos e materiais compositos reforcados com fibra e vidro

    Oushiro, Karol B.; Costa, Anahi P. da; Botelho, Edson C. [UNESP, Guaratingueta, SP (Brazil). Faculdade de Engenharia. Dept. de Materiais e Tecnologia], e-mail:; Costa, Michelle L. [UNESP, Guaratingueta, SP (Brazil). Faculdade de Engenharia. Dept. de Materiais e Tecnologia; Instituto de Aeronautica e Espaco (AMR/IAE/DCTA), Sao Jose dos Campos, SP (Brazil). Div. de Materiais


    The appearance of defects, mainly thinning caused by corrosion, is unavoidable in pipeline transport of fluids. Many repair techniques have been developed, among them, has been highlighting the pipeline repair with composite that is to involve the passage of the corroded pipeline with composite material. The study of these techniques is of great interest for the branch industry, since the efficiency of repair will depend on good adhesion between the repair composite and steel pipe. In this work, the bond strength between fiber glass/epoxy composite bonded to a steel tubing used in petrochemical plants was evaluated by mechanical testing of lap shear (ASTM D1002). These samples were conditioned using 2000 thermal shock cycles, and the mechanical results of the conditioned and non-conditioned samples were compared. With this, we observed that the polymer composites can be successfully used for repair of metallic pipes with petrochemical application, because when exposed to sudden temperature changes their mechanical properties (shear) remained practically unchanged. (author)

  16. Vibration Analysis of Composite Rectangular Plates Reinforced along Curved Lines

    Honda, Shinya; Oonishi, Yoshimasa; Narita, Yoshihiro; Sasaki, Katsuhiko

    In the past few decades, composite materials composed of straight fibers and polymer matrix have gained their status as the most promising material for light-weight structures. Technical merit of the composites as tailored material also provided practical advantages in the optimum design process. Recently, it is reported that the fabrication machine has been developed to make curved fibers embedded in the matrix material. Based on such technical advancement, this paper proposes an analytical method to study vibration of composite rectangular plates reinforced along curved lines. The approach is based on the Ritz method where variable fiber direction can be accommodated. For this purpose, the fibers continuously changing their direction are formulated as the variable bending stiffness in the total potential energy. A frequency equation is derived by the Ritz minimizing process, and frequency parameters are calculated as the eigenvlaues in the eigenvalue problem. In numerical results, the accuracy of the method is presented by comparing present results with FEM results. The advantages of present plate are confirmed by comparing natural frequencies and mode shapes with those of conventional composite and isotropic plates, and the effectiveness of the new solution to the most recent problem is demonstrated.

  17. Nanographene reinforced carbon/carbon composites

    Bansal, Dhruv

    Carbon/Carbon Composites (CCC) are made of carbon reinforcement in carbon matrix and have high thermal stability and fatigue resistance. CCC are used in nose cones, heat shields and disc brakes of aircrafts due to their exceptional mechanical properties at high temperature. The manufacturing process of CCC involves a carbonization stage in which unwanted elements, except carbon, are eliminated from the polymer precursor. Carbonization results in the formation of voids and cracks due to the thermal mismatch between the reinforcement and the matrix and expulsion of volatiles from the polymer matrix. Thermal cracks and voids decrease the density and mechanical properties of the manufactured CCC. In this work, Nanographene Platelets (NGP) were explored as nanofillers to fill the voids/cracks and reduce thermal shrinkage in CCC. They were first compared with Vapor Grown Carbon Nanofibers (VGCNF) by dispersion of different concentrations (0.5wt%, 1.5wt%, 3wt%) in resole-type phenolic resin and were characterized to explore their effect on rheology, heat of reaction and wetting behavior. The dispersions were then cured to form nanocomposites and were characterized for morphology, flexure and thermal properties. Finally, NGP were introduced into the carbon/carboncomposites in two stages, first by spraying in different concentrations (0.5wt%, 1.5wt%, 3wt%, 5wt %) during the prepreg formation and later during densification by directly mixing in the corresponding densification mix. The manufactured NGP reinforced CCC were characterized for microstructure, porosity, bulk density and mechanical properties (Flexure and ILSS) which were further cross-checked by non-destructive techniques (vibration and ultrasonic). In this study, it was further found that at low concentration (≤ 1.5 wt%) NGP were more effective in increasing the heat of reaction and in decreasing the viscosity of the phenolic resin. The decrease in viscosity led to better wetting properties of NGP / phenolic

  18. Study on the preparation of fibers reinforced gypsum-based foamed composite materials%纤维增强石膏发泡材料的研制

    李淋淋; 李国忠


    以脱硫建筑石膏、粉煤灰、发泡剂为原材料制备发泡脱硫石膏保温材料。研究不同发泡剂掺量对其密度、力学性能和导热系数的影响,结果表明,发泡剂掺量为5%时,导热系数最小,为0.052 W/(m·K),此时脱硫石膏发泡材料的密度为225 kg/m3。利用玻璃纤维作为增强材料,研究了玻璃纤维的掺加对材料强度的影响。结果表明,当玻璃纤维掺量为1.5%时,试样的抗折强度提高了41.67%。%The paper researches a kind of insulation foamed desulfurization gypsum material prepared by the desulfurization gypsum, foaming agent and fly ash from the aspects of the influence of different content of foaming agent on its density, mechanical properties and thermal conductivity. The result shows that when the content of foaming agent is 5%, the thermal conductivity is minimum heat conduction coefficient of 0.052 W/(m·K), and the density of foamed desulfurization gypsum is 225 kg/m3 . And also researches the effect of additive content of glass fiber as reinforcing material on strength of the material. The result shows that when the content of glass fiber is 1.5%, the transverse strength of the sample increases 41.67%.

  19. Carbon fiber reinforced thermoplastic composites for future automotive applications

    Friedrich, K.


    After a brief introduction to polymer composite properties and markets, the state of the art activities in the field of manufacturing of advanced composites for automotive applications are elucidated. These include (a) long fiber reinforced thermoplastics (LFT) for secondary automotive components, and (b) continuous carbon fiber reinforced thermosetting composites for car body applications. It is followed by future possibilities of carbon fiber reinforced thermoplastic composites for e.g. (i) crash elements, (ii) racing car seats, and (iii) production and recycling of automotive fenders.

  20. Synthesis and Characterization of TiB2 Reinforced Aluminium Matrix Composites: A Review

    Kumar, Narendra; Gautam, Gaurav; Gautam, Rakesh Kumar; Mohan, Anita; Mohan, Sunil


    Aluminium-matrix composites (AMCs) are developed to meet the demands of light weight high performance materials in aerospace, automotive, marine and other applications. The properties of AMCs can be tailored suitably by combinations of matrix, reinforcement and processing route. AMCs are one of the most attractive alternatives for the manufacturing of light weight and high strength parts due to their low density and high specific strength. There are various techniques for preparing the AMCs with different reinforcement particles. In AMCs, the reinforcements are usually in the form of metal oxides, carbides, borides, nitrides and their combination. Among the various reinforcements titanium di-boride (TiB2) is of much interest due to its excellent stiffness, hardness, and wear resistance. This paper attempts to provide an overview to explore the possibilities of synthesizing titanium di-boride reinforced AMCs with different techniques. The mechanical and tribological properties of these composites have been emphasized to project these as tribo-materials.

  1. High elastic modulus nanopowder reinforced resin composites for dental applications

    Wang, Yijun


    Dental restorations account for more than $3 billion dollars a year on the market. Among them, all-ceramic dental crowns draw more and more attention and their popularity has risen because of their superior aesthetics and biocompatibility. However, their relatively high failure rate and labor-intensive fabrication procedure still limit their application. In this thesis, a new family of high elastic modulus nanopowder reinforced resin composites and their mechanical properties are studied. Materials with higher elastic modulus, such as alumina and diamond, are used to replace the routine filler material, silica, in dental resin composites to achieve the desired properties. This class of composites is developed to serve (1) as a high stiffness support to all-ceramic crowns and (2) as a means of joining independently fabricated crown core and veneer layers. Most of the work focuses on nano-sized Al2O3 (average particle size 47 nm) reinforcement in a polymeric matrix with 50:50 Bisphenol A glycidyl methacrylate (Bis-GMA): triethylene glycol dimethacrylate (TEGDMA) monomers. Surfactants, silanizing agents and primers are examined to obtain higher filler levels and enhance the bonding between filler and matrix. Silane agents work best. The elastic modulus of a 57.5 vol% alumina/resin composite is 31.5 GPa compared to current commercial resin composites with elastic modulus alumina, diamond/resin composites are studied. An elastic modulus of about 45 GPa is obtained for a 57 vol% diamond/resin composite. Our results indicate that with a generally monodispersed nano-sized high modulus filler, relatively high elastic modulus resin-based composite cements are possible. Time-dependent behavior of our resin composites is also investigated. This is valuable for understanding the behavior of our material and possible fatigue testing in the future. Our results indicate that with effective coupling agents and higher filler loading, viscous flow can be greatly decreased due to the


    Rawls, G.


    The goal of the overall project is to successfully adapt spoolable FRP currently used in the oil industry for use in hydrogen pipelines. The use of FRP materials for hydrogen service will rely on the demonstrated compatibility of these materials for pipeline service environments and operating conditions. The ability of the polymer piping to withstand degradation while in service, and development of the tools and data required for life management are imperative for successful implementation of these materials for hydrogen pipeline. The information and data provided in this report provides the technical basis for the codification for fiber reinforced piping (FRP) for hydrogen service. The DOE has invested in the evaluation of FRP for the delivery for gaseous hydrogen to support the development of a hydrogen infrastructure. The codification plan calls for detailed investigation of the following areas: System design and applicable codes and standards; Service degradation of FRP; Flaw tolerance and flaw detection; Integrity management plan; Leak detection and operational controls evaluation; Repair evaluation. The FRP codification process started with commercially available products that had extensive use in the oil and gas industry. These products have been evaluated to assure that sufficient structural integrity is available for a gaseous hydrogen environment.



    If the reinforcers were spheroids or ellipsoids, and their volume fraction was no more than 10%, their interactions could be neglected so that the elastic modulus of the composites could be predicted accurately[1~4]. However, in practical short-fiber/whisker reinforced metal matrix composites, the volume fraction of reinforcers is as high as 15%~40%. Additionally, the shape of reinforcers is usually far much more complicated than that of spheroids or ellipsoids and their distribution is irregular. The distance between reinforcers is usually as small as their diameter, so that it is difficult to cut out a unit cell with only a singular reinforcer included. For this kind of engineering composites, accurate prediction of effective elastic moduli is still an open problem until now[5].  In Refs.[6, 7], based on the study of strain distribution in whisker reinforced composites, the ratio of the root-mean-square strain of reinforcers to the macro linear strain along the same direction is defined as deformation characteristic parameter λf. An explicit precise stiffness tensor is derived by introducing λf and distribution density function of reinforcers, which is able to predict the stiffness modulus of composites with arbitrary whisker orientation under any loading condition. However, accurate prediction of the present theory depends on the value of λf.  In the present paper, the relation between λf and the microstructure geometrical and physical parameters of the composite will be investigated with a shear lag model[8] and network model[9] in order to derive a regressive formula for λf. As an example of verification, the tensile stress-strain curve of a whisker reinforced metal matrix composite will be predicted and compared with experiments.

  4. The influence of stiffeners on axial crushing of glass-fabric-reinforced epoxy composite shells

    A. Vasanthanathan


    Full Text Available A generic static and impact experimental procedure has been developed in this work aimed at improving the stability of glass fabric reinforced epoxy shell structures by bonding with axial stiffeners. Crashworthy structures fabricated from composite laminate with stiffeners would offer energy absorption superior to metallic structures under compressive loading situations. An experimental material characterisation of the glass fabric reinforced epoxy composite under uni-axial tension has been carried out in this study. This work provides a numerical simulation procedure to describe the static and dynamic response of unstiffened glass fabric reinforced epoxy composite shell (without stiffeners and stiffened glass fabric reinforced epoxy composite shell (with axial stiffeners under static and impact loading using the Finite Element Method. The finite element calculation for the present study was made with ANSYS®-LS-DYNA® software. Based upon the experimental and numerical investigations, it has been asserted that glass fabric reinforced epoxy shells stiffened with GFRP stiffeners are better than unstiffened glass fabric reinforced epoxy shell and glass fabric reinforced epoxy shell stiffened with aluminium stiffeners. The failure surfaces of the glass fabric reinforced epoxy composite shell structures tested under impact were examined by SEM.

  5. Joining of the AMC Composites Reinforced with Ti3Al Intermetallic Particles by Resistance Butt Welding

    Adamiak M.


    Full Text Available The introduction of new reinforcing materials continues to be investigated to improve the final behaviour of AMCs as well as to avoid some drawbacks of using ceramics as reinforcement. The present work investigates the structure, properties and ability of joining aluminium EN-AW 6061 matrix composite materials reinforced with Ti3Al particles by resistance butt welding as well as composite materials produced by mechanical milling, powder metallurgy and hot extrusion techniques. Mechanically milled and extruded composites show finer and better distribution of reinforcement particles, which leads to better mechanical properties of the obtained products. Finer microstructure improves mechanical properties of obtained composites. The hardness increases twice in the case of mechanically milled composites also, a higher reinforcement content results in higher particle dispersion hardening, for 15 wt.% of intermetallics reinforcement concentration composites reach about 400 MPa UTS. Investigation results of joints show that best hardness and tensile properties of joints can be achieved by altering soft conditions of butt welding process e.g. current flow time 1.2 s and current 1400 A. To improve mechanical properties of butt welding joints age hardening techniques can also be used.

  6. Mechanical properties of thermoplastic composites reinforced with Entada Mannii fibre

    Oluwayomi BALOGUN


    Full Text Available The mechanical properties and fracture mechanisms of thermoplastic composites reinforced with Entada mannii fibres was investigated. Polypropylene reinforced with 1, 3, 5, and 7 wt% KOH treated and untreated Entada mannii fibres were processed using a compression moulding machine. The tensile properties, impact strength, and flexural properties of the composites were evaluated while the tensile fracture surface morphology was examined using scanning electron microscopy. The results show that reinforcing polypropylene with Entada mannii fibres resulted in improvement of the tensile strength and elastic modulus. This improvement is remarkable for 5 wt% KOH treated Entada mannii fibre reinforced composites by 28 % increase as compared with the unreinforced polypropylene. The composites reinforced with Entada mannii fibres also had impact strength values of 70 % higher than the unreinforced polypropylene. However, the polypropylene reinforced with 5 and 7wt% KOH treated fibres exhibited significantly higher flexural strength and Young’s modulus by 53% and 52% increase as compared with the unreinforced polypropylene. The fracture surface of the polypropylene composites reinforced with untreated Entada mannii fibres were characterized by fibre debonding, fibre pull-out and matrix yielding while less voids and fibre pull-outs are observed in the composites reinforced with KOH treated Entada mannii fibres. v

  7. Continuous jute fibre reinforced laminated paper composite and reinforcement-fibre free paper laminate

    B B Verma


    Plastic bags create a serious environmental problem. The proposed jute fibre reinforced laminated paper composite and reinforcement-fibre free paper laminate may help to combat the war against this pollutant to certain extent. The paper laminate, without reinforcement fibre, exhibited a few fold superiority in tensile properties than single paper strip. The studies further show that an appreciable improvement in tensile properties can be achieved by introducing continuous jute fibre in paper laminates.

  8. Multifunctional Laminated Composite Materials for Protective Clothing

    Nermin M. Aly


    Full Text Available Protective clothing performs a vital role in maintaining the safety of human in workplace. The developments in this field are proceeding to fulfill the needs with multifunctional materials at competitive costs. Recently, the protective clothing field introduces the usage of composite materials taking advantage of their outstanding properties. In this paper, the multifunctional performance of hybrid laminated composites (HLC was investigated aiming to be utilized in protective clothing. The influences of reinforcement and resin properties on the physical properties of the laminated composites and their resistance to puncture load and UV transmittance were studied. ANOVA test was used for the statistical analysis of the results. The results showed that, the reinforcement material and structure and the fiber/matrix interface have major influences on the laminated composites performance. It was revealed that, the HLC fabricated from (polyester/glass fabric with satin 4 structure and nonwoven glass fiber mat exhibited the best functional performance.

  9. Multifunctional composites using reinforced laminae with carbon-nanotube forests

    Veedu, Vinod P.; Cao, Anyuan; Li, Xuesong; Ma, Kougen; Soldano, Caterina; Kar, Swastik; Ajayan, Pulickel M.; Ghasemi-Nejhad, Mehrdad N.


    Traditional fibre-reinforced composite materials with excellent in-plane properties fare poorly when out-of-plane through-thickness properties are important. Composite architectures with fibres designed orthogonal to the two-dimensional (2D) layout in traditional composites could alleviate this weakness in the transverse direction, but all of the efforts so far have only produced limited success. Here, we unveil an approach to the 3D composite challenge, without altering the 2D stack design, on the basis of the concept of interlaminar carbon-nanotube forests that would provide enhanced multifunctional properties along the thickness direction. The carbon-nanotube forests allow the fastening of adjacent plies in the 3D composite. We grow multiwalled carbon nanotubes on the surface of micro-fibre fabric cloth layouts, normal to the fibre lengths, resulting in a 3D effect between plies under loading. These nanotube-coated fabric cloths serve as building blocks for the multilayered 3D composites, with the nanotube forests providing much-needed interlaminar strength and toughness under various loading conditions. For the fabricated 3D composites with nanotube forests, we demonstrate remarkable improvements in the interlaminar fracture toughness, hardness, delamination resistance, in-plane mechanical properties, damping, thermoelastic behaviour, and thermal and electrical conductivities making these structures truly multifunctional.

  10. A physically-based abrasive wear model for composite materials

    Lee, Gun Y.; Dharan, C.K.H.; Ritchie, Robert O.


    A simple physically-based model for the abrasive wear of composite materials is presented based on the mechanics and mechanisms associated with sliding wear in soft (ductile) matrix composites containing hard (brittle) reinforcement particles. The model is based on the assumption that any portion of the reinforcement that is removed as wear debris cannot contribute to the wear resistance of the matrix material. The size of this non-contributing portion of the reinforcement is estimated by modeling the three primary wear mechanisms, specifically plowing, interfacial cracking and particle removal. Critical variables describing the role of the reinforcement, such as its relative size and the nature of the matrix/reinforcement interface, are characterized by a single contribution coefficient, C. Predictions are compared with the results of experimental two-body (pin-on drum) abrasive wear tests performed on a model aluminum particulate-reinforced epoxy matrix composite material.

  11. Investigation of crack paths in natural fibre-reinforced composites

    S. Keck


    Full Text Available Nowadays, fibre-reinforced composite materials are widely used in many fields, e.g. automotive and aerospace. Natural fibres such as flax and hemp provide good density specific mechanical properties. Additionally, the embodied production energy in natural fibres is much smaller than in synthetic ones. Within this paper the fracture mechanical behaviour of flax fibre-reinforced composites is discussed. Especially, this paper focuses on the determination and investigation of crack paths in compact tension specimens with three different fibre directions under a static as well as fatigue load. Differences and similarities in the obtained crack paths under different loading conditions are presented. Due to the pronounced orthotropic behaviour of those materials the crack path is not only governed by the stress state, but practically determined by the fibre direction and fibre volume fraction. Therefore, the well-known stress intensity factor solutions for the standard specimens are not applicable. It is necessary to carry out extensive numerical simulations to evaluate the stress intensity factor evolution along the growing crack in order to be able to determine fatigue crack growth rate curves. Those numerical crack growth simulations are performed with the three-dimensional crack simulation program ADAPCRACK3D to gain energy release rates and in addition stress intensity factors

  12. 四种纤维复合加固材料性能对比分析%Comparative analysis on performance of four kinds of composite fiber reinforcement materials



    The paper introduces the definition,merits and categories of fiber strengthening composite material,briefly analyzes several fiber com-posite reinforcement materials,makes a discussion from aspects of physical and chemical indicators,obtains merits and defects of basalt fiber, and puts forward relevant suggestions,which will be good for promoting and studying fiber composite material.%介绍了纤维增强复合材料的定义、优点及分类,对几种不同种类的纤维复合加固材料进行了简要分析,从物理化学指标方面进行了论述,得到了玄武岩纤维材料的优缺点,并提出了相关建议,有利于纤维复合材料的研究与推广应用。

  13. Silicon carbide reinforced silicon carbide composite

    Lau, Sai-Kwing (Inventor); Calandra, Salvatore J. (Inventor); Ohnsorg, Roger W. (Inventor)


    This invention relates to a process comprising the steps of: a) providing a fiber preform comprising a non-oxide ceramic fiber with at least one coating, the coating comprising a coating element selected from the group consisting of carbon, nitrogen, aluminum and titanium, and the fiber having a degradation temperature of between C. and C., b) impregnating the preform with a slurry comprising silicon carbide particles and between 0.1 wt % and 3 wt % added carbon c) providing a cover mix comprising: i) an alloy comprising a metallic infiltrant and the coating element, and ii) a resin, d) placing the cover mix on at least a portion of the surface of the porous silicon carbide body, e) heating the cover mix to a temperature between C. and C. to melt the alloy, and f) infiltrating the fiber preform with the melted alloy for a time period of between 15 minutes and 240 minutes, to produce a ceramic fiber reinforced ceramic composite.

  14. Topographical Parameter Characteristics of Dry Sliding Surfaces of Particle-Reinforced Aluminum Composites

    陈跃; 上官宝; 张永振; 孙乐民; 铁喜顺; 夏跃虹


    Generally, friction and wear occur on the surface of the materials.It is necessary to investigate the dry sliding friction and wear behavior of surface.In this paper, 3-D topographical parameters were used to investigate the topographical characteristics of dry sliding surfaces for particle-reinforced aluminum composites on semi-metallic friction material.The experimental results indicate that the surface topography of the particle-reinforced aluminum composites can be divided into two types, the flaking-off pit type and the groove type.The composites whose surface topography is the flaking-off pit type possess superior heat conductivity and bearing area, lower wear rate, and higher friction coefficient than the groove type.Consequently, the flaking-off pit type surface topography is much better than the groove type for particle-reinforced aluminum composites on semi-metallic friction materials in dry sliding.

  15. Impact and dynamic mechanical thermal properties of textile silk reinforced epoxy resin composites

    Yang, K.; Guan, J.


    Silk fabric reinforced epoxy resin composites (SFRPs) were prepared using simple techniques of hand lay-up, hot-press and vacuum treatment, and a series of volume fractions of silk reinforcements were achieved. The impact properties and dynamic mechanical properties of SFRPs were investigated using a pendulum impact testing method and dynamic mechanical thermal analysis (DMTA). The results suggest that silk reinforcement could greatly enhance the mechanical performances of SFRPs. The impact strength reached a maximum of 71 kJ/m2 for 60%-silk SFRP, which demonstrated a potential of silk composites for defence and impact- resistant materials.

  16. An anisotropic constitutive model with biaxial-tension coupling for woven composite reinforcements

    Yao, Yuan; Huang, Xiaoshuang; Peng, Xiongqi; Gong, Youkun


    Based on fiber reinforced continuum mechanics theory, an anisotropic hyperelastic constitutive model with biaxial tension coupling for woven composite reinforcements is developed. Experimental data from literature are used to identify material parameters in the constitutive model for a specific balanced plain woven fabric. The developed model is validated by comparing numerical results with experimental biaxial tension data under different stretch ratios and picture-frame shear data, demonstrating that the developed constitutive model is highly suitable to characterize the highly non-linear and strongly anisotropic mechanical behaviors of woven composite reinforcements under large deformation.

  17. A Deformation Model for Dispersely Failing Elastoplastic Unidirectionally Reinforced Composites

    Lagzdins, A.


    A calculation model is proposed for unidirectionally reinforced elastoplastic composites capable of gradually accumulating disperse microdamages under loading. The composite is assumed to be a homogeneous transversely isotropic solid. To describe its elastoplastic behavior, an incremental plasticity theory with a nonlinear combined hardening mechanism is invoked. At each point of the solid, its damage is characterized by a centrally symmetric scalar function on a unit sphere. This function is approximated by a fourth-rank tensor, which is used for describing the degradation of the elastic properties of the solid due to the accumulation of disperse microdamages. It is shown how to determine, using the known experimental data, all material constants appearing in the theoretical relations suggested.

  18. Modeling oxidation damage of continuous fiber reinforced ceramic matrix composites

    Cheng-Peng Yang; Gui-Qiong Jiao; Bo Wang


    For fiber reinforced ceramic matrix composites (CMCs), oxidation of the constituents is a very important damage type for high temperature applications. During the oxidizing process, the pyrolytic carbon interphase gradually recesses from the crack site in the axial direction of the fiber into the interior of the material. Carbon fiber usually presents notch-like or local neck-shrink oxidation phenomenon, causing strength degradation. But, the reason for SiC fiber degradation is the flaw growth mechanism on its surface. A micromechanical model based on the above mechanisms was established to simulate the mechanical properties of CMCs after high temperature oxidation. The statistic and shearlag theory were applied and the calculation expressions for retained tensile modulus and strength were deduced, respectively. Meanwhile, the interphase recession and fiber strength degradation were considered. And then, the model was validated by application to a C/SiC composite.

  19. Effect of hybrid fiber reinforcement on the cracking process in fiber reinforced cementitious composites

    Pereira, Eduardo B.; Fischer, Gregor; Barros, Joaquim A.O.


    The simultaneous use of different types of fibers as reinforcement in cementitious matrix composites is typically motivated by the underlying principle of a multi-scale nature of the cracking processes in fiber reinforced cementitious composites. It has been hypothesized that while undergoing...... tensile deformations in the composite, the fibers with different geometrical and mechanical properties restrain the propagation and further development of cracking at different scales from the micro- to the macro-scale. The optimized design of the fiber reinforcing systems requires the objective...... assessment of the contribution of each type of fiber to the overall tensile response. Possible synergistic effects resulting from particular combinations of fibers need to be clearly identified. In the present study, the evaluation of the response of different fiber reinforced cementitious composite...

  20. Carbon Fiber Reinforced Glass Matrix Composites for Space Based Applications.


    composite plates were prepared using standard i, c-pressing procedures. The plates were cut into tensile specimens which were then subsequently notched...reinforced HMU composites were prepared using the matrix compositions and hot-pressing parameters shown in Table VI-1. The compositions are identical...shown in Figure VI-6. Traces of a- cristobalite are present in all three composites, with a noticeably larger amount present in the Nb20 5 composite. All

  1. Method of producing particulate-reinforced composites and composties produced thereby

    Han, Qingyou; Liu, Zhiwei


    A process for producing particle-reinforced composite materials through utilization of an in situ reaction to produce a uniform dispersion of a fine particulate reinforcement phase. The process includes forming a melt of a first material, and then introducing particles of a second material into the melt and subjecting the melt to high-intenisty acoustic vibration. A chemical reaction initiates between the first and second materials to produce reaction products in the melt. The reaciton products comprise a solide particulate phase, and the high-intensity acoustic vibration fragments and/or separates the reaction products into solid particles that are dispersed in the melt and are smaller than the particles of the second material. Also encompassed are particles-reinforced composite materials produced by such a process.

  2. Multi-length Scale Material Model Development for Armorgrade Composites


    synthesis -/processing-induced defects; (c) effect of 3 synthesis -/processing-induced defects on PPTA-fiber properties; (d) effect of fiber-/ yarn ...Derivation of the Materials Constitutive Relations for Carbon Nanotube Reinforced Poly-Vinyl-Ester-Epoxy Based Composites,” Journal of Materials Science, 42...fabric or PPTA-fiber-reinforced polymer-matrix composites. Specifically, the role of various material- synthesis -/fiber-processing-induced defects, as

  3. Rheocasting a Zn-Al composite reinforced with coke dust

    Madroñero, A.; Cruz, J.; Foruria, C.; Coleto, J.


    This article details research conducted to establish the optimum parameters needed to rheocast a zinc-aluminum alloy reinforced with coke-dust particles. Based on the experiments, a composite with a 10 vol.% coke-particulate reinforcement was found to exhibit good metallurgical quality (e.g., low porosity and the absence of clustering) in the final product.

  4. Development of high performance fiber reinforced cement composites (HPFRCC for application as a transition layer of reinforced beams

    V. J. Ferrari

    Full Text Available This study presents the development and behavior analysis of high performance fiber reinforced cement composites (HPFRCC. The describedmaterials were specifically developed for application as a transition layer: a repair layer that constitutes the stressed chord of reinforcedconcrete beams strengthened in flexure with carbon fiber reinforced polymers (CFRP. Nineteen different composites were produced by thehybridization process, varying the conventional short steel fiber and steel microfiber (manufactured exclusively for this research contentsto modify the microstructure of the material, thus enhancing the stress transfer process from the cement matrix to the fibers. To analyze theresponse to flexural loading, the composites underwent three point bending tests in notched prism specimens. The response of the materialwas obtained considering strength and tenacity parameters (flexural and fracture. There was evidence of high performance by the composites with a pseudo-hardening behavior.

  5. Key Role of Reinforcing Structures in the Flame Retardant Performance of Self-Reinforced Polypropylene Composites

    Katalin Bocz


    Full Text Available The flame retardant synergism between highly stretched polymer fibres and intumescent flame retardant systems was investigated in self-reinforced polypropylene composites. It was found that the structure of reinforcement, such as degree of molecular orientation, fibre alignment and weave type, has a particular effect on the fire performance of the intumescent system. As little as 7.2 wt % additive content, one third of the amount needed in non-reinforced polypropylene matrix, was sufficient to reach a UL-94 V-0 rating. The best result was found in self-reinforced polypropylene composites reinforced with unidirectional fibres. In addition to the fire retardant performance, the mechanical properties were also evaluated. The maximum was found at optimal consolidation temperature, while the flame retardant additive in the matrix did not influence the mechanical performance up to the investigated 13 wt % concentration.

  6. Evaluation on mechanical properties of woven aloevera and sisal fibre hybrid reinforced epoxy composites

    A Shadrach Jeya Sekaran; K Palani Kumar; K Pitchandi


    Natural fibres as reinforcement in polymer composite for making low-cost materials are growing day by day. Researcher’s main attention is to apply appropriate technology to utilize these natural fibres as effectively and economically as possible to produce good quality fibre-reinforced polymer composites for various engineering applications. In this research, the experiments of tensile, flexural and impact tests were carried out for woven aloevera and sisal fibre hybrid-reinforced epoxy composites. The hand layup method of fabrication was employed in preparing the composites. The surface morphology of the composites was examined through scanning electron microscope. Due to the low-density and high-specific properties of sisal fibre composites, it offer cost savings when compared with synthetic fibres. Hence it has very good implications in the automotive and transportation industry.

  7. Investigation into hemp fiber-and whisker-reinforced soy protein composites

    Linxiang WANG; Rakesh KUMAR; Lina ZHANG


    Whiskers, designated as W, were prepared from hemp fibers. Both fibers and whiskers were characterized by Fourier transform infrared spectroscopy, thermogravi-metric analysis. Scanning electron microscopy and transmission electron microscopy were used to evaluate the dimensions of the fibers and whiskers, respectively.By incorporating different weight fraction of the fibers and whiskers into soy protein isolate, we prepared two different composites designated as SC and SC-W,respectively. Thiodiglycol was used as a plasticizer for the preparation of composites. The SC and SC-W composites were characterized and compared in terms of mechanical properties, volume fraction of porosity,and water uptake. The results indicated that there was not much significant difference in the properties of the composites. In fact, mechanical properties of fiber-reinforced composites were higher than whisker-reinforced composites at optimum weight fractions.This study can give us the idea about the judicious use of fibers or whiskers as reinforcement materials.

  8. Physical and Mechanical Properties of Composites and Light Alloys Reinforced with Detonation Nanodiamonds

    Sakovich, G. V.; Vorozhtsov, S. A.; Vorozhtsov, A. B.; Potekaev, A. I.; Kulkov, S. N.


    The influence of introduction of particles of detonation-synthesized nanodiamonds into composites and aluminum-base light alloys on their physical and mechanical properties is analyzed. The data on microstructure and physical and mechanical properties of composites and cast aluminum alloys reinforced with diamond nanoparticles are presented. The introduction of nanoparticles is shown to result in a significant improvement of the material properties.

  9. Life of structures of composite materials

    Koznetsov, N.D.; Stepanenko, N.D.


    The introduction of composite materials in gas turbine engines is rationally done in stages. It is desirable to concentrate efforts on the use of them for production of vanes, sound deadening panes, the reverse rod, and other elements of the stator. The authors use compressor blades as an example of the basic principles of design, the selection of the reinforcing structure, and inspection of the quality of structures of composite materials. A method of determination of the elastodamping properties of polymer composite materials on specimens with free ends in high frequency flexural vibrations excited by a modulated jet of compressed air has been developed and standardized. With the use of this method such defects as separations, cracks, disorientation of the reinforcing, deviations in the order of alternation and the angular orientation of the layers are revealed.

  10. Composite Materials and Sandwich Structures - A Primer


    quality and protects prepreg from handling damage. Non - woven unidirectional tapes can otherwise split between fibers. Clean, white lint-free cotton ...applications and S glass fibers are used in strength critical situations. S glass fibers are sometimes woven in composite materials to increase toughness...A woven form of the reinforcements (Figure 1b) is also used in certain cases, depending on the application of the composite. Figure 1a- Fiber


    Romildo Dias Tolêdo Filho


    Full Text Available ABSTRACT The inclusion of fibre reinforcement in concrete, mortar and cement paste can enhance many of the engineering properties of the basic materials, such as fracture toughness, flexural strength and resistance to fatigue, impact, thermal shock and spalling. In recent years, a great deal of interest has been created worldwide on the potential applications of natural fibre reinforced, cement based composites. Investigations have been carried out in many countries on various mechanical properties, physical performance and durability of cement based matrices reinforced with naturally occurring fibres including sisal, coconut, jute, bamboo and wood fibres. These fibres have always been considered promising as reinforcement of cement based matrices because of their availability, low cost and low consumption of energy. In this review, the general properties of the composites are described in relation to fibre content, length, strength and stiffness. A chronological development of sisal fibre reinforced, cement based matrices is reported and experimental data are provided to illustrate the performance of sisal fibre reinforced cement composites. A brief description on the use of these composite materials as building products has been included. The influence of sisal fibres on the development of plastic shrinkage in the pre-hardened state, on tensile, compressive and bending strength in the hardened state of mortar mixes is discussed. Creep and drying shrinkage of the composites and the durability of natural fibres in cement based matrices are of particular interest and are also highlighted. The results show that the composites reinforced with sisal fibres are reliable materials to be used in practice for the production of structural elements to be used in rural and civil construction. This material could be a substitute asbestos-cement composite, which is a serious hazard to human and animal health and is prohibited in industrialized countries. The


    季葆华; 王自强


    A micromechanical model is developed to simulate the mechanical behaviors of discontinuous reinforced composites. The analysis for a representative unit cell is based on the assumption of a periodic array of aligned reinforcements.The minimum energy principle is used to determine the unknown coefficients of the displacement field of the unit cell. The constitutive behavior of composites is studied to obtain the relationship between the main variables of matrix and reinforcements.It is concluded that the flow strength of composites is strongly influenced by volume fraction, aspect ratio of reinforcement, and the strain hardening exponent of matrix.An analytical constitutive relation of composites is obtained. The predicted results are in agreement with the existing experimental and numerical results.

  13. Research on Flax Fiber Reinforced Polylactide Environmental Friendly Composite

    WANG Chun-hong; WANG Rui; LIU Ming; SHEN Lu; BIAN Dong-cai


    Biodegradable polylactide acid (PLA) resin can be combined with flax fibers to produce biodegradable composite materials. In our study, commercial PLA fibers were mixed with flax fibers by a non-woven method so as to make nonwoven pre-forms, which can be generated into flax fiber reinforced PLA environmental friendly composites by heat pressing technology. The tensile, flexural and impact properties are tested in order to evaluate the basic physical properties of the composites, and the influenced factors listed as making technology of the pre-forms, weight ratio of flax fibers and heat pressing technology are discussed and optimized, which can be described as weight ratio of flax fibers and PLA fibers is 50/50, heating temperature, time and pressure are respectively 195℃, 20 min and 12.5 Mpa.Preliminary results show that mechanical properties of the flax/PLA composites are quite promising compared with flax/PP composites in common commercial automotive use.Scanning electron microscope (SEM) is used to analyze the tensile specimen fracture surfaces, which shows voids and gaps occurring between flax fibers and PLA matrix and sign of fiber pull-out, the strength of flax/PLA interface can be further improved.

  14. Fracture and fatigue of discontinuously reinforced copper/tungsten composites

    Harris, B.; Ramani, S. V.


    The strength, toughness and resistance to cyclic crack propagation of composites consisting of copper reinforced with short tungsten wires of various lengths have been studied and the results compared with the behavior of continuously reinforced composites manufactured by the same method, i.e., by vacuum hot-pressing. It has been found that whereas the resistance to fatigue crack growth of continuously reinforced composites is very similar to that of continuous Al/stainless steel composites reported elsewhere, the addition of short fibers completely changes the mode of fracture, and no direct comparisons are possible. In effect, short fibers inhibit single crack growth by causing plastic flow to be distributed rather than localized, and although these composites are much less strong than continuous fiber composites, they nevertheless have much greater fatigue resistance.

  15. Smart damping of laminated fuzzy fiber reinforced composite shells using 1-3 piezoelectric composites

    Kundalwal, S. I.; Kumar, R. Suresh; Ray, M. C.


    This paper deals with the investigation of active constrained layer damping (ACLD) of smart laminated continuous fuzzy fiber reinforced composite (FFRC) shells. The distinct constructional feature of a novel FFRC is that the uniformly spaced short carbon nanotubes (CNTs) are radially grown on the circumferential surfaces of the continuous carbon fiber reinforcements. The constraining layer of the ACLD treatment is considered to be made of vertically/obliquely reinforced 1-3 piezoelectric composite materials. A finite element (FE) model is developed for the laminated FFRC shells integrated with the two patches of the ACLD treatment to investigate the damping characteristics of the laminated FFRC shells. The effect of variation of the orientation angle of the piezoelectric fibers on the damping characteristics of the laminated FFRC shells has been studied when the piezoelectric fibers are coplanar with either of the two mutually orthogonal vertical planes of the piezoelectric composite layer. It is revealed that radial growth of CNTs on the circumferential surfaces of the carbon fibers enhances the attenuation of the amplitude of vibrations and the natural frequencies of the laminated FFRC shells over those of laminated base composite shells without CNTs.

  16. Effect of Moisture Absorption Behavior on Mechanical Properties of Basalt Fibre Reinforced Polymer Matrix Composites

    Amuthakkannan Pandian


    Full Text Available The study of mechanical properties of fibre reinforced polymeric materials under different environmental conditions is much important. This is because materials with superior ageing resistance can be satisfactorily durable. Moisture effects in fibre reinforced plastic composites have been widely studied. Basalt fibre reinforced unsaturated polyester resin composites were subjected to water immersion tests using both sea and normal water in order to study the effects of water absorption behavior on mechanical properties. Composites specimens containing woven basalt, short basalt, and alkaline and acid treated basalt fibres were prepared. Water absorption tests were conducted by immersing specimens in water at room temperature for different time periods till they reached their saturation state. The tensile, flexural, and impact properties of water immersed specimens were conducted and compared with dry specimens as per the ASTM standard. It is concluded that the water uptake of basalt fibre is considerable loss in the mechanical properties of the composites.

  17. Recent progress in NASA Langley Research Center textile reinforced composites program

    Dexter, H. Benson; Harris, Charles E.; Johnston, Norman J.


    Research was conducted to explore the benefits of textile reinforced composites for transport aircraft primary structures. The objective is to develop and demonstrate the potential of affordable textile reinforced composite materials to meet design properties and damage tolerance requirements of advanced aircraft structural concepts. Some program elements include development of textile preforms, processing science, mechanics of materials, experimental characterization of materials, and development and evaluation of textile reinforced composite structural elements and subcomponents. Textile 3-D weaving, 3-D braiding, and knitting and/or stitching are being compared with conventional laminated tape processes for improved damage tolerance. Through-the-thickness reinforcements offer significant damage tolerance improvements. However, these gains must be weighted against potential loss in in-plane properties such as strength and stiffness. Analytical trade studies are underway to establish design guidelines for the application of textile material forms to meet specific loading requirements. Fabrication and testing of large structural parts are required to establish the potential of textile reinforced composite materials.

  18. The Effect of Pre-Tension on Deformation Behaviour of Natural Fabric Reinforced Composite



    Full Text Available In the fiber-reinforced composites industry together with the promotion of environmental friendly production, synthetic materials are attempted to be replaced by renewable, biodegradable and recyclable materials. The most important challenge is to improve strength and durability of these materials. Matrix that supports the fiber-reinforcement in composite generally is brittle and deformation causes fragmentation of the matrix. Pre-tension of reinforcement is a well-known method to increase tensile strength of woven material. The current study develops the idea to use pre-tension of woven fabric in order to improve quality and strength properties of the obtained composite. Natural (cotton fiber and synthetic (glass fiber woven fabrics were investigated. The pressure forming operation was carried out in order to study clamping imposed strain variation across the surface of woven fabric. The uniaxial tension test of single-layer composite specimens with and without pre-tension was performed to study the effect of pre-tension on strength properties of composite. The results have shown that pre-tension imposed by clamping is an effective method to improve the quality of shaped composite parts (more smoothed contour is obtained and to increase the strength properties of composite reinforced by woven natural fabric. After pre-tension the tensile strength at break increased in 12 % in warp direction, in 58 % in weft direction and in 39 % in bias direction.

  19. The influence of matrix composition and reinforcement type on the properties of polysialate composites

    Hammell, James A.

    There is a critical need for the development of materials for eliminating fire as a cause of death in aircraft accidents. Currently available composites that use organic matrices not only deteriorate at temperatures above 300°C but also emit toxic fumes. The results presented in this dissertation focus on the development of an inorganic matrix that does not burn or emit toxic fumes. The matrix, known as polysialate, can withstand temperatures in excess of 1000°C. The matrix behaves like a ceramic, but does not need high curing temperatures, so it can be processed like many common organic matrices. The major parameters evaluated in this dissertation are: (i) Influence of reinforcement type, (ii) Matrix formulation for both wet-dry durability and high temperature resistance, (iii) Influence of processing variables such as moisture reduction and storage, (iv) Tensile strain capacity of modified matrices and matrices reinforced with ceramic microfibers and discrete carbon fibers, and (v) analytical modeling of mechanical properties. For the reinforcement type; carbon, glass, and stainless steel wire fabrics were investigated. Carbon fabrics with 1, 3, 12, and 50k tows were used. A matrix chemical formulation that can withstand wetting and drying was developed. This formulation was tested at high temperatures to ascertain its stability above 400°C. On the topic of processing, shelf life of prepregged fabric layers and efficient moisture removal methods were studied. An analytical model based on layered reinforcement was developed for analyzing flexural specimens. It is shown that the new inorganic matrix can withstand wetting and drying, and also high temperature. The layered reinforcement concept provides accurate prediction of strength and stiffness for composites reinforced with 1k and 3k tows. The prepregged fabric layers can be stored for 14 days at -15°C without losing strength.

  20. Creep Forming of Carbon-Reinforced Ceramic-Matrix Composites

    Vaughn, Wallace L.; Scotti, Stephan J.; Ashe, Melissa P.; Connolly, Liz


    A set of lecture slides describes an investigation of creep forming as a means of imparting desired curvatures to initially flat stock plates of carbon-reinforced ceramic-matrix composite (C-CMC) materials. The investigation is apparently part of a continuing effort to develop improved means of applying small CCMC repair patches to reinforced carbon-carbon leading edges of aerospace vehicles (e.g., space shuttles) prior to re-entry into the atmosphere of the Earth. According to one of the slides, creep forming would be an intermediate step in a process that would yield a fully densified, finished C-CMC part having a desired size and shape (the other steps would include preliminary machining, finish machining, densification by chemical vapor infiltration, and final coating). The investigation included experiments in which C-CMC disks were creep-formed by heating them to unspecified high temperatures for time intervals of the order of 1 hour while they were clamped into single- and double-curvature graphite molds. The creep-formed disks were coated with an oxidation- protection material, then subjected to arc-jet tests, in which the disks exhibited no deterioration after exposure to high-temperature test conditions lasting 490 seconds.

  1. Development of niobium aluminide-based composites with improved toughness using treated reinforcements

    Woytera, S.A.; Bhagat, R.B.; Amateau, M.F. [Pennsylvania State Univ., University Park, PA (United States). Applied Research Lab.


    Many ordered intermetallic compounds exhibit attractive properties for high temperature structural aerospace applications. The major obstacles limiting the use of these materials are their low ductility and toughness at room temperature and poor creep resistance at elevated temperatures. In this investigation treated silicon carbide whisker and niobium particle reinforced niobium aluminide matrix composites have been fabricated by reaction hot pressing in vacuum. Elemental matrix powders react exothermally and form the niobium aluminide matrix in situ. A suitable hot pressing cycle has been established for the successful development of the niobium aluminide matrix, while reducing adverse reactions between the matrix and the reinforcements. The composites with treated reinforcements are expected to have high resistance to creep at elevated temperatures and they show relatively low hardness and higher toughness in comparison with the composites reinforced with untreated whiskers.

  2. Investigations of mechanical and wear properties of alumina/titania/fire-clay reinforced epoxy composites

    Patel, Vinay Kumar; Chauhan, Shivani; Sharma, Aarushi


    In this work, the effect of various particulates (alumina, titania, fire clay) reinforcements on mechanical and wear properties of epoxy composites have been studied with a prime motive of replacing the costly alumina and titania by much economical fire clay for high mechanical strength and/or wear resistant materials. Fire clay based epoxy composites delivered better mechanical (both tensile and impact) properties than the alumina filled or neat epoxy composites and slightly lower than titania reinforced composites, which qualified the fire clay a very suitable cost effective alternatives of both alumina and titania for high mechanical strength based applications. However, the poor wear behavior of fire clay reinforced composites revealed its poor candidacy for wear and tear applications.

  3. Tribological Potential of Hybrid Composites Based on Zinc and Aluminium Alloys Reinforced with SiC and Graphite Particles

    D. Džunić


    Full Text Available The paper reviews contemporary research in the area of hybrid composites based on zinc and aluminium alloys reinforced with SiC and graphite particles. Metal matrix composites (MMCs based on ZA matrix are being increasingly applied as light-weight and wear resistant materials. Aluminium matrix composites with multiple reinforcements (hybrid AMCsare finding increased applications because of improved mechanical and tribological properties and hence are better substitutes for single reinforced composites. The results of research show that the hybrid composites possess higher hardness, higher tensile strength, better wear resistance and lower coefficient of friction when compared to pure alloys.

  4. Strength and deformability of concrete beams reinforced by non-metallic fiber and composite rebar

    Kudyakov, K. L.; Plevkov, V. S.; Nevskii, A. V.


    Production of durable and high-strength concrete structures with unique properties has always been crucial. Therefore special attention has been paid to non-metallic composite and fiber reinforcement. This article describes the experimental research of strength and deformability of concrete beams with dispersed and core fiber-based reinforcement. As composite reinforcement fiberglass reinforced plastic rods with diameters 6 mm and 10 mm are used. Carbon and basalt fibers are used as dispersed reinforcement. The developed experimental program includes designing and production of flexural structures with different parameters of dispersed fiber and composite rebar reinforcement. The preliminary testing of mechanical properties of these materials has shown their effectiveness. Structures underwent bending testing on a special bench by applying flexural static load up to complete destruction. During the tests vertical displacements were recorded, as well as value of actual load, slippage of rebars in concrete, crack formation. As a result of research were obtained structural failure and crack formation graphs, value of fracture load and maximum displacements of the beams at midspan. Analysis of experimental data showed the effectiveness of using dispersed reinforcement of concrete and the need for prestressing of fiberglass composite rebar.

  5. High Performance Fiber Reinforced Cement Composites 6 HPFRCC 6

    Reinhardt, Hans; Naaman, A


    High Performance Fiber Reinforced Cement Composites (HPFRCC) represent a class of cement composites whose stress-strain response in tension undergoes strain hardening behaviour accompanied by multiple cracking, leading to a high strain prior to failure. The primary objective of this International Workshop was to provide a compendium of up-to-date information on the most recent developments and research advances in the field of High Performance Fiber Reinforced Cement Composites. Approximately 65 contributions from leading world experts are assembled in these proceedings and provide an authoritative perspective on the subject. Special topics include fresh and hardening state properties; self-compacting mixtures; mechanical behavior under compressive, tensile, and shear loading; structural applications; impact, earthquake and fire resistance; durability issues; ultra-high performance fiber reinforced concrete; and textile reinforced concrete. Target readers: graduate students, researchers, fiber producers, desi...

  6. Investigations on Void Formation in Composite Molding Processes and Structural Damping in Fiber-Reinforced Composites with Nanoscale Reinforcements

    DeValve, Caleb Joshua

    Fiber-reinforced composites (FRCs) offer a stronger and lighter weight alternative to traditional materials used in engineering components such as wind turbine blades and rotorcraft structures. Composites for these applications are often fabricated using liquid molding techniques, such as injection molding or resin transfer molding. One significant issue during these processing methods is void formation due to incomplete wet-out of the resin within the fiber preform, resulting in discontinuous material properties and localized failure zones in the material. A fundamental understanding of the resin evolution during processing is essential to designing processing conditions for void-free filling, which is the first objective of the dissertation. Secondly, FRCs used in rotorcraft experience severe vibrational loads during service, and improved damping characteristics of the composite structure are desirable. To this end, a second goal is to explore the use of matrix-embedded nanoscale reinforcements to augment the inherent damping capabilities in FRCs. The first objective is addressed through a computational modeling and simulation of the infiltrating dual-scale resin flow through the micro-architectures of woven fibrous preforms, accounting for the capillary effects within the fiber bundles. An analytical model is developed for the longitudinal permeability of flow through fibrous bundles and applied to simulations which provide detailed predictions of local air entrapment locations as the resin permeates the preform. Generalized design plots are presented for predicting the void content and processing time in terms of the Capillary and Reynolds Numbers governing the molding process. The second portion of the research investigates the damping enhancement provided to FRCs in static and rotational configurations by different types and weight fractions of matrix-embedded carbon nanotubes (CNTs) in high fiber volume fraction composites. The damping is measured using

  7. The effect of reinforcement volume ratio on porosity and thermal conductivity in Al-Mgo composites

    Recep Calin


    Full Text Available In this study, the effects of reinforcement volume ratios (RVR on composite structure and thermal conductivity were examined in Al-MgO reinforced metal matrix composites (MMCs of 5%, 10% and 15% RVR produced by melt stirring. In the production of composites, EN AW 1050A aluminum alloy was used as the matrix material and MgO powders with particle size of -105 µm were used as the reinforcement material. For every composite specimen was produced at 500 rev/min stirring speed, at 750 °C liquid matrix temperature and 4 minutes stirring time. Composite samples were cooled under normal atmosphere. Then, microstructures of the samples were determined and evaluated by using Scanning Electron Microscope (SEM and Energy Dispersive X-ray Spectroscopy (EDS analysis. In general, it was observed that the reinforcement exhibited a homogeneous distribution. Furthermore, it was determined that the increase in the RVR increased porosity. From the Scanning Electron Microscope images, a thermal Ansys model was generated to determine effective thermal conductivity. Effective thermal conductivity of Al-MgO composites increased with the decrease in reinforcement volume ratio.

  8. Deformation behavior of metallic glass composites reinforced with shape memory nanowires studied via molecular dynamics simulations

    Şopu, D.; Stoica, M.; Eckert, J.


    Molecular dynamics simulations indicate that the deformation behavior and mechanism of Cu64Zr36 composite structures reinforced with B2 CuZr nanowires are strongly influenced by the martensitic phase transformation and distribution of these crystalline precipitates. When nanowires are distributed in the glassy matrix along the deformation direction, a two-steps stress-induced martensitic phase transformation is observed. Since the martensitic transformation is driven by the elastic energy release, the strain localization behavior in the glassy matrix is strongly affected. Therefore, the composite materials reinforced with a crystalline phase, which shows stress-induced martensitic transformation, represent a route for controlling the properties of glassy materials.

  9. Bioactive Glass Fiber Reinforced Starch-Polycaprolactone Composite for Bone Applications

    Jukola, H.; Nikkola, L.; Gomes, M. E.; Chiellini, F.; Tukiainen, M.; Kellomäki, M.; Chiellini, E.; Reis, R. L.; Ashammakhi, N.


    For bone regeneration and repair, combinations of different materials are often needed. Biodegradable polymers are often combined with osteoconductive materials, such as bioactive glass (BaG), which can also improve the mechanical properties of the composite. The aim of this study was to develop and characterize BaG fiber-reinforced starch-poly-ɛ-caprolactone (SPCL) composite. Sheets of SPCL (30/70 wt%) were produced using single-screw extrusion. They were then cut and compression molded in layers with BaG fibers to form composite structures of different combinations. Thermal, mechanical, and degradation properties of the composites were studied. The actual amount of BaG in the composites was determined using combustion tests. A strong endothermic peak indicating melting at about 56 °C was observed by differential scanning calorimetry (DSC) analysis. Thermal gravimetry analysis (TGA) showed that thermal decomposition of SPCL started at 325 °C with the decomposition of starch and continued at 400 °C with the degradation of polycaprolactone (PCL). Initial mechanical properties of the reinforced composites were at least 50% better than the properties of the non-reinforced composites. However, the mechanical properties of the composites after two weeks of hydrolysis were comparable to those of the non-reinforced samples. During the six weeks' hydrolysis the mass of the composites had decreased only by about 5%. The amount of glass in the composites remained the same for the six-week period of hydrolysis. In conclusion, it is possible to enhance the initial mechanical properties of SPCL by reinforcing it with BaG fibers. However, the mechanical properties of the composites are only sufficient for use as filler material and they need to be further improved to allow long-lasting bone applications.

  10. Characterization of silane coated hollow sphere alumina-reinforced ultra high molecular weight polyethylene composite as a possible bone substitute material

    S Roy; S Pal


    Silane coated hollow sphere alumina ceramic particles were moulded with ultra high molecular weight polyethylene (UHMWPE) to form a series of composites with alumina weight percent in the range from 15 to 50. The composites were prepared in a cylindrical mould using powder-processing technique. The composites were characterized for mechanical properties using destructive and non-destructive ultrasonic testing methods. The physical properties of the composite were determined and compared with those of cortical bone.

  11. The Effects of Weathering on Mechanical Properties of Glass Fiber Reinforced Plastics (Grp) Materials

    Abdullah, H.; S. Al Araimi and R. A. Siddiqui


    Glass fiber reinforced plastics composite is extensively used as a structural material for pools, oil pipes and tanks because it has good corrosion resistance properties.  The effects of weathering on the mechanical properties of glass fiber reinforced plastics (GRP) in the Sultanate of Oman have been studied.  The tensile and three point bend specimens were exposed to outdoor conditions (open atmosphere) in sunlight and tested for various intervals of time.  It was observed th...

  12. Design and realization a skiff racing boat hull made of natural fibers reinforced composite

    Collotta, M.; Solazzi, L.; Pandini, S.; Tomasoni, G.; Alberti, M.; Donzella, G.


    This paper discusses the development of a racing boat with an hull made of a composite material reinforced by natural fibers. In particular, we report here the design and realization of the boat hull, the assessment of its mechanical performance by means of a computer assisted simulation, and the cost analysis to assess the economic sustainability of the new composite developed. The results have shown that the new composite has a performance comparable with conventional glass fiber reinforced composites employed for the realization of this type of boat, accordingly to the technology employed and the lamination sequence adopted. Moreover, the FEM analysis performed over the skiff of the designed and constructed boat has demonstrated a successful choice of the material for real application, as it was later confirmed by the good performance of the boat in water. Finally, the cost analysis highlighted the economic sustainability of the new composite, allowing a cost saving of over 28% with respect to carbon fiber composites.

  13. Modeling and simulation of continuous fiber-reinforced ceramic composites

    Bheemreddy, Venkata

    Finite element modeling framework based on cohesive damage modeling, constitutive material behavior using user-material subroutines, and extended finite element method (XFEM), are developed for studying the failure behavior of continuous fiber-reinforced ceramic matrix composites (CFCCs) by the example of a silicon carbide matrix reinforced with silicon carbide fiber (SiC/SiCf) composite. This work deals with developing comprehensive numerical models for three problems: (1) fiber/matrix interface debonding and fiber pull-out, (2) mechanical behavior of a CFCC using a representative volume element (RVE) approach, and (3) microstructure image-based modeling of a CFCC using object oriented finite element analysis (OOF). Load versus displacement behavior during a fiber pull-out event was investigated using a cohesive damage model and an artificial neural network model. Mechanical behavior of a CFCC was investigated using a statistically equivalent RVE. A three-step procedure was developed for generating a randomized fiber distribution. Elastic properties and damage behavior of a CFCC were analyzed using the developed RVE models. Scattering of strength distribution in CFCCs was taken into account using a Weibull probability law. A multi-scale modeling framework was developed for evaluating the fracture behavior of a CFCC as a function of microstructural attributes. A finite element mesh of the microstructure was generated using an OOF tool. XFEM was used to study crack propagation in the microstructure and the fracture behavior was analyzed. The work performed provides a valuable procedure for developing a multi-scale framework for comprehensive damage study of CFCCs.

  14. Micromechanics of Composite Materials

    Dvorak, George


    This book presents a broad exposition of analytical and numerical methods for modeling composite materials, laminates, polycrystals and other heterogeneous solids, with emphasis on connections between material properties and responses on several length scales, ranging from the nano and microscales to the macroscale. Many new results and methods developed by the author are incorporated into a rich fabric of the subject, which has been explored by several researchers over the last 40 years.   The first  part of the book reviews anisotropic elasticity theory, and then it describes the frequently used procedures and theorems for bounding and estimating overall properties, local fields and energy changes in elastic inhomogeneities, heterogeneous media, fiber composites and functionally graded materials.  Those are caused by mechanical loads and by phase eigenstrains, such as thermal, transformation and inelastic strains, and also by cavities and cracks.    Worked examples show that the eigendeformations may...

  15. Pyrolysis of reinforced polymer composites: Parameterizing a model for multiple compositions

    Martin, Geraldine E.

    A single set of material properties was developed to describe the pyrolysis of fiberglass reinforced polyester composites at multiple composition ratios. Milligram-scale testing was performed on the unsaturated polyester (UP) resin using thermogravimetric analysis (TGA) coupled with differential scanning calorimetry (DSC) to establish and characterize an effective semi-global reaction mechanism, of three consecutive first-order reactions. Radiation-driven gasification experiments were conducted on UP resin and the fiberglass composites at compositions ranging from 41 to 54 wt% resin at external heat fluxes from 30 to 70 kW m -2. The back surface temperature was recorded with an infrared camera and used as the target for inverse analysis to determine the thermal conductivity of the systematically isolated constituent species. Manual iterations were performed in a comprehensive pyrolysis model, ThermaKin. The complete set of properties was validated for the ability to reproduce the mass loss rate during gasification testing.

  16. A Study of Strength Transfer from tow to Textile Composite Using Different Reinforcement Architectures

    Cristian, Irina; Nauman, Saad; Boussu, Francois; Koncar, Vladan


    The paper proposes an experimental and analytical approach of designing composites with the predetermined ultimate strength, reinforced with warp interlock fabrics. In order to better understand the phenomena of transfer of tensile properties from a tow to the composite, intermediate phases of composite manufacturing have also been taken into account and tensile properties of tows taken from the loom and the woven reinforcements have also been tested. Process of transfer of mechanical properties of raw materials to the final product (composite) depends on various structural factors. Here the influence of weave structure, which ultimately influences crimp has been studied. A strength transfer coefficient has been proposed which helps in estimating the influence of architectural parameters on 3D woven composites. 3 woven interlock reinforcements were woven to form composites. The coefficients of strength transfer were calculated for these three variants. The structural parameters were kept the same for these three reinforcements except for the weave structure. In was found that the phenomenon of strength transfer from tow to composite is negatively influenced by the crimp. In general the strength transfer coefficients have higher values for dry reinforcements and afterwards due to resin impregnation the values drop.

  17. Mechanical Properties of Nonwoven Reinforced Thermoplastic Polyurethane Composites.

    Tausif, Muhammad; Pliakas, Achilles; O'Haire, Tom; Goswami, Parikshit; Russell, Stephen J


    Reinforcement of flexible fibre reinforced plastic (FRP) composites with standard textile fibres is a potential low cost solution to less critical loading applications. The mechanical behaviour of FRPs based on mechanically bonded nonwoven preforms composed of either low or high modulus fibres in a thermoplastic polyurethane (TPU) matrix were compared following compression moulding. Nonwoven preform fibre compositions were selected from lyocell, polyethylene terephthalate (PET), polyamide (PA) as well as para-aramid fibres (polyphenylene terephthalamide; PPTA). Reinforcement with standard fibres manifold improved the tensile modulus and strength of the reinforced composites and the relationship between fibre, fabric and composite's mechanical properties was studied. The linear density of fibres and the punch density, a key process variable used to consolidate the nonwoven preform, were varied to study the influence on resulting FRP mechanical properties. In summary, increasing the strength and degree of consolidation of nonwoven preforms did not translate to an increase in the strength of resulting fibre reinforced TPU-composites. The TPU composite strength was mainly dependent upon constituent fibre stress-strain behaviour and fibre segment orientation distribution.

  18. Microstructure and hardness of WC-Co particle reinforced iron matrix surface composite

    Zhang Peng; Zeng Shaolian; Zhang Zhiguo


    In this study, a high Cr cast iron surface composite material reinforced with WC-Co particles 2-6 mm in size was prepared using a pressureless sand mold infiltration casting technique. The composition, microstructure and hardness were determined by means of energy dispersive spectrometry (EDS), electron probe microanalysis (EPMA), scanning electron microscope (SEM) and Rockwell hardness measurements. It is determined that the obtained composite layer is about 15 mm thick with a WC-Co particle...

  19. Processing and damage recovery of intrinsic self-healing glass fiber reinforced composites

    Sordo, Federica; Michaud, Véronique


    Glass fiber reinforced composites with a self-healing, supramolecular hybrid network matrix were produced using a modified vacuum assisted resin infusion moulding process adapted to high temperature processing. The quality and fiber volume fraction (50%) of the obtained materials were assessed through microscopy and matrix burn-off methods. The thermo-mechanical properties were quantified by means of dynamic mechanical analysis, revealing very high damping properties compared to traditional epoxy-based glass fiber reinforced composites. Self-healing properties were assessed by three-point bending tests. A high recovery of the flexural properties, around 72% for the elastic modulus and 65% of the maximum flexural stress, was achieved after a resting period of 24 h at room temperature. Recovery after low velocity impact events was also visually observed. Applications for this intrinsic and autonomic self-healing highly reinforced composite material point towards semi-structural applications where high damping and/or integrity recovery after impact are required.

  20. Finite-Element Analysis of Jute- and Coir-Fiber-Reinforced Hybrid Composite Multipanel Plates

    Nirbhay, M.; Misra, R. K.; Dixit, A.


    Natural-fiber-reinforced polymer composite materials are rapidly gaining interest worldwide both in terms of research and industrial applications. The present work includes the characterization and modeling of jute- and coir-fiber-reinforced hybrid composite materials. The mechanical behavior of a two-panel plate and a sixpanel box structure is analyzed under various loading regimes by using the finite-element software ABAQUS®. Exhaustive parametric studies are also performed to obtain a clear insight into the relationships between various parameters and deflections of the panels and stress distributions in them. Deflections of both the structures are compared and found to be in good agreement with published results. To determine the mechanical behavior of natural-fiber-reinforced composite panels, a finite-element analysis is performed.

  1. Spring forward of woven fabric reinforced composites

    Wijskamp, Sebastiaan; Lamers, E.A.D.; Akkerman, Remko


    Continuous-fibre-reinforced plastic products are usually formed at elevated temperatures. They exhibit distortions when they are cooled to room temperature and released from the mould. For example, the enclosed angle of an L-shaped product decreases, see Fig. 1. This effect is known as

  2. Service life prediction and fibre reinforced cementitious composites

    Stoklund Larsen, E.

    The present Ph.D.thesis addresses the service life concept on the fibre reinforced cementitious composites. The advantages and problems of adding fibre to a cementitious matrix and the influence on service life are described. In SBI Report 221, Service life prediction and cementitious somposites......, the factors affecting the pure cementitious composite are described. Different sizes and types of fibre reinforced crmentitious composites have been chosen to illustrate different ageing and deterioration mechanisms. Some ageing mechanisms can be accelerated and others cannot which is demonstrated in a test...

  3. Micromechanisms of damage in unidirectional fiber reinforced composites

    Mishnaevsky, Leon; Brøndsted, Povl


    Numerical micromechanical investigations of the mechanical behavior and damage evolution of glass fiber reinforced composites are presented. A program code for the automatic generation of 3D micromechanical unit cell models of composites with damageable elements is developed, and used in the nume...

  4. Flows in polymers, reinforced polymers and composites a multi-scale approach

    Binetruy, Christophe; Keunings, Roland


    This book gives a detailed and practical introduction to complex flows of polymers and reinforced polymers as well as the flow of simple fluids in complex microstructures. Over the last decades, an increasing number of functional and structural parts, made so far with metals, has been progressively reengineered by replacing metallic materials by polymers, reinforced polymers and composites. The motivation for this substitution may be the weight reduction, the simpler, cheaper or faster forming process, or the ability to exploit additional functionalities. The present Brief surveys modern developments related to the multi-scale modeling and simulation of polymers, reinforced polymers, that involve a flowing microstructure and continuous fiber-reinforced composites, wherein the fluid flows inside a nearly stationary multi-scale microstructure. These developments concern both multi-scale modeling, defining bridges between the micro and macro scales - with special emphasis on the mesoscopic scale at which kinetic...

  5. Engineered cementitious composites for strengthening masonry infilled reinforced concrete frames

    Dehghani, Ayoub; Nateghi-Alahi, Fariborz; Fischer, Gregor


    The results of the second part of a comprehensive experimental program, aimed at investigating the behavior of masonry infilled reinforced concrete (RC) frames strengthened with fiber reinforced engineered cementitious composites (ECC) used as an overlay on the masonry wall, are presented in this...... and energy absorption capacity of the infilled frame, prevent brittle failure modes in the infill wall, and provide a reasonable system overstrength....

  6. Hybrid Composites Based on Carbon Fiber/Carbon Nanofilament Reinforcement

    Mehran Tehrani


    Full Text Available Carbon nanofilament and nanotubes (CNTs have shown promise for enhancing the mechanical properties of fiber-reinforced composites (FRPs and imparting multi-functionalities to them. While direct mixing of carbon nanofilaments with the polymer matrix in FRPs has several drawbacks, a high volume of uniform nanofilaments can be directly grown on fiber surfaces prior to composite fabrication. This study demonstrates the ability to create carbon nanofilaments on the surface of carbon fibers employing a synthesis method, graphitic structures by design (GSD, in which carbon structures are grown from fuel mixtures using nickel particles as the catalyst. The synthesis technique is proven feasible to grow nanofilament structures—from ethylene mixtures at 550 °C—on commercial polyacrylonitrile (PAN-based carbon fibers. Raman spectroscopy and electron microscopy were employed to characterize the surface-grown carbon species. For comparison purposes, a catalytic chemical vapor deposition (CCVD technique was also utilized to grow multiwall CNTs (MWCNTs on carbon fiber yarns. The mechanical characterization showed that composites using the GSD-grown carbon nanofilaments outperform those using the CCVD-grown CNTs in terms of stiffness and tensile strength. The results suggest that further optimization of the GSD growth time, patterning and thermal shield coating of the carbon fibers is required to fully materialize the potential benefits of the GSD technique.

  7. Influence of the Geometric Parameters on the Mechanical Behaviour of Fabric Reinforced Composite Laminates

    Axinte, Andrei; Taranu, Nicolae; Bejan, Liliana


    A polymer fabric reinforced composite is a high performance material, which combines strength of the fibres with the flexibility and ductility of the matrix. For a better drapeability, the tows of fibres are interleaved, resulting the woven fabric, used as reinforcement. The complex geometric shape of the fabric is of paramount importance in establishing the deformability of the textile reinforced composite laminates. In this paper, an approach based on Classical Lamination Theory ( CLT), combined with Finite Element Methods ( FEM), using Failure Analysis and Internal Load Redistribution, is utilised, in order to compare the behaviour of the material under specific loads. The main goal is to analyse the deformability of certain types of textile reinforced composite laminates, using carbon fibre satin as reinforcement and epoxy resin as matrix. This is accomplished by studying the variation of the in-plane strains, given the fluctuation of several geometric parameters, namely the width of the reinforcing tow, the gap between two consecutive tows, the angle of laminae in a multi-layered configuration and the tows fibre volume fraction.

  8. Processing and characterization of redmud reinforced polypropylene composites

    Shanmugavel, R.; Jayamani, M.; Nagarajan, R.; Irullappasamy, S.; Cardona, F.; Sultan, M. T. H.


    In this work, the redmud reinforced polypropylene composites were fabricated by compression molding setup. The effects of the redmud content on the mechanical, melting and crystalline behavior of the composites was investigated. The melting and crystalline behavior of the composites were investigated using Digital Scanning Calorimeter. The test results show that hardness of the composites increases with increasing redmud content while incorporation of redmud content decreases tensile and impact strength of the composites. It is determined that the addition of redmud on the polypropylene does not affect the crystalline behavior of the composites.

  9. Test Methods for Measuring Material Properties of Composite Materials in all Three Material Axes


    conducted using ASTM D 6641/D 6641M “Standard Test Method for Determining the Compressive Properties of Polymer Matrix Composite Laminates Using a Combined...D 7291/D 7291M “Standard Test Method for Through-Thickness “Flatwise” Tensile Strength and Elastic Modulus of a Fiber- Reinforced Polymer Matrix Composite Material...34Flatwise" Tensile Strength and Elastic Modulus of a Fiber-Reinforced Polymer Matrix Composite Material”. West Conshohocken, PA, 2005, DOI: 10.1520/D7291

  10. Biotechnology and Composite Materials


    Biotechnology, in general terms, is the science and engineering of using living organisms for making useful products such as pharmaceuticals, foods , fuels...chemicals, materials or in waste treatment processes and clinical and chemical analyses. It encompases the prosaic form of using yeast cells to make...ductile component of the composite. Table 1. Mechanical Properties of Ceramics, Cermets, and Abalone Shell •if KIC Hardness MPa MPam 1n 2 /2 Mohs KIlN

  11. Composites materials for friction and braking application

    Crăciun, A. L.; Pinca-Bretotean, C.; Birtok-Băneasă, C.; Josan, A.


    The brake pads are an important component in the braking system of automotive. Materials used for brake pads should have stable and reliable frictional and wear properties under varying conditions of load, velocity, temperature and high durability. These factors must be satisfied simultaneously which makes it difficult to select effective brake pads material. The paper presents the results of the study for characterisation of the friction product used for automotive brake pads. In the study it was developed four frictional composites by using different percentages of coconut fibres (0%, 5%, 10%, 15%) reinforcement in aluminium matrix. The new composites tested in the laboratory, modelling appropriate percentage ratio between matrix and reinforcement volume and can be obtained with low density, high hardness properties, good thermal stability, higher ability to hold the compressive force and have a stable friction coefficient. These characteristics make them useful in automotive industry.

  12. Studying Impact Damage on Carbon-Fiber Reinforced Aircraft Composite Panels with Sonicir

    Han, Xiaoyan; Zhao, Xinyue; Zhang, Ding; He, Qi; Song, Yuyang; Lubowicki, Anthony; Newaz, Golam.; Favro, Lawrence D.; Thomas, Robert L.


    Composites are becoming more important materials in commercial aircraft structures such as the fuselage and wings with the new B787 Dreamliner from Boeing which has the target to utilize 50% by weight of composite materials. Carbon-fiber reinforced composites are the material of choice in aircraft structures. This is due to their light weight and high strength (high strength-to-weight ratio), high specific stiffness, tailorability of properties, design flexibility etc. Especially, by reducing the aircraft's body weight by using such lighter structures, the cost of fuel can be greatly reduced with the high jet fuel price for commercial airlines. However, these composites are prone to impact damage and the damage may occur without any observable sign on the surface, yet resulting in delaminations and disbonds that may occur well within the layers. We are studying the impact problem with carbon-fiber reinforced composite panels and developing SonicIR for this application as a fast and wide-area NDE technology. In this paper, we present our results in studying composite structures including carbon-fiber reinforced composite materials, and preliminary quantitative studies on delamination type defect depth identification in the panels.

  13. Indirect composite resin materials for posterior applications.

    Shellard, E; Duke, E S


    Indirect composite resin restorations were introduced a number of years ago as possible alternatives to traditional metallic or ceramic-based indirect restorations. However, the earlier formulations did not provide evidence of improvement in mechanical and physical properties over chairside-placed direct composite resin materials. Because they required more tooth structure removal than direct restorations, their use became unpopular and was abandoned by most clinicians. Over the past few years, a new class of composite resin indirect materials has surfaced in the profession. Various technologies have been suggested as reinforcement mechanisms. Fibers, matrix modifications, and an assortment of innovations have been proposed for enhancing indirect composite resin restorations. Applications are from inlay restorations all the way to multi-unit fixed prostheses. This manuscript summarizes some of the progress made in this area. When available, data is presented to provide clinicians with guidelines and indications for the use of these materials.

  14. Fibreglass as an alternative to wood poles : Transmission and distribution poles and crossarms : use of fiber reinforced composite materials for overhead electric utility lines

    Wiles, J.R. [Shakespeare Composites and Electronics, Newberry, SC (United States)


    For over thirty years, Shakespeare Composites and Electronics has manufactured fiberglass composite lighting and utility poles, as well as being the number one maker of composite crossarms. Composite poles have a few advantages, such as being lightweight, they do no rust, are woodpecker and termite resistant, use no harmful chemicals, and have long life. A chart displaying the comparative pole weights is presented. The key design factors of fiberglass composite utility poles are: pole diameter, fiberglass type and wind angle, layers (thickness) of fiberglass, resin type and formulation, resin mix consistency, cure cycle and maximum curing temperature, and others. Two charts were also displayed presenting 40 feet class 4 pole bending strengths and 40 feet class 2 pole bending strengths. The author indicated that composite poles have a better strength consistency than wood, while being as consistent as steel and prestressed concrete. The design is based on an overload factor of safety of 2.5 for numerous installations. Some of the analytical methods used include mechanical testing, finite element modeling, and thermal analysis. The author describes in detail the concerns associated with attachments. Coating consists of a system of ultra violet blockers in the resin followed by an added resin rich polyester veil outer surface. In addition, there is a proprietary coating process with additional ultra violet blockers. Quality control is effected at the plant. The weathering system lasts 80 years. figs.

  15. Simulation of a Novel Joining Process for Fiber-Reinforced Thermoplastic Composites and Metallic Components

    Gude, M.; Freund, A.; Vogel, C.; Kupfer, R.


    In this study, a new joining technology to produce hybrid structures with continuous-fiber-reinforced thermoplastics and metallic components is presented adapting the concept of classical clinching for thermoplastic composites. To demonstrate the capability of the thermoclinching process, prototypic joints were manufactured using an experimental joining installation developed. Nondestructive and destructive analyses of the thermoclinched joints showed that a relocation of the reinforcement into the neck and head area of the joining zone could be achieved. For a first estimation of the maximum load-carrying capacity of the joints, single-lap specimens with both reinforced and nonreinforced thermoplastics were manufactured and tested, revealing up to 50% higher failure loads of the reinforced joints. To understand the local material configuration and to achieve a defined and adjustable fabric structure in the head area of the joint, further analyses with regard to material- and tool-side conditions of the joining zone are necessary.

  16. Fracture morphology of carbon fiber reinforced plastic composite laminates

    Vinod Srinivasa; Vinay Shivakumar; Vinay Nayaka; Sunil Jagadeeshaiaih; Murali Seethram; Raghavendra Shenoy; Abdelhakim Nafidi


    Carbon fiber reinforced plastic (CFRP) composites have been extensively used in fabrication of primary structures for aerospace, automobile and other engineering applications. With continuous and widespread use of these composites in several advanced technology, the frequency of failures is likely to increase. Therefore, to establish the reasons for failures, the fracture modes should be understood thoroughly and unambiguously. In this paper, CFRP composite have been tested in tension, compre...

  17. Numerical simulation of mechanical behavior of composite materials

    Oller, Sergio


    An original mechanical formulation to treat nonlinear orthotropic behavior of composite materials is presented in this book. It also examines different formulations that allow us to evaluate the behavior of composite materials through the composition of its components, obtaining a new composite material. Also two multiple scale homogenization methods are given, one based on the analytical study of the cells (Ad-hoc homogenization), and other one, more general based on the finite element procedure applied on the macro scale (upper-scale) and in the micro scale (sub-scale). A very general formulation to simulate the mechanical behavior for traditional composite structures (plywood, reinforced concrete, masonry, etc.), as well as the new composite materials reinforced with long and short fibers, nanotubes, etc., are also shown in this work. Typical phenomena occurring in composite materials are also described in this work, including fiber-matrix debounding, local buckling of fibers and its coupling with the over...

  18. Warm compaction of Al2O3 particulate reinforced powder metallurgy iron-base composite

    倪东惠; 陈维平; 肖志瑜; 邵明; 张双益


    Mechanical properties of the warm compacted alumina particulate reinforced powder metallurgy composite materials was compared with those of the materials obtained by conventional cold compaction. Factors affecting the properties of the warm compacted material such as compaction temperature, lubricant content and alumina content were studied. A 3%(mass fraction) alumina particulate reinforced iron-base composite with a green density of 7.0g/cm3 can be obtained by pressing the powder with a pressure of 700MPa at 175℃. The sintered materials have a density of 6.88g/cm3, a tensile strength of 512MPa and an elongation of 1.3%. Results show that as alumina content increases, density and mechanical properties of the composite decrease.

  19. Development of textile-reinforced carbon fibre aluminium composites manufactured with gas pressure infiltration methods

    W. Hufenbach


    Full Text Available Purpose: The aim of his paper is to show potential of textile-reinforced carbon fibre aluminium composite with advantage of the lightweight construction of structural components subjected to thermo-mechanical stress.Design/methodology/approach: The manufacture of specimens of the carbon fibre-reinforced aluminium was realised with the aid of an advanced differential gas pressure infiltration technique, which was developed at ILK, TU Dresden.Findings: The gas pressure infiltration technology enables to fabricate complex carbon aluminium composites with fibre or textile reinforcement using moulds of graphite, but in future development the optimization of infiltration process is required. The load-adapted combination of 3D reinforced semi-finished fibre products (textile preforms made from carbon fibres (CF with aluminium light metal alloys (Al offers a considerable lightweight construction potential, which up to now has not been exploited.Research limitations/implications: Gas pressure infiltration technology enables to fabricate complex carbon aluminium composites with fibre or textile reinforcement using precision moulds of graphite, but in future development the optimization of infiltration process is required.Practical implications: Load-adapted CF/Al-MMC, due to the relatively high stiffness and strength of the metal matrix, allow the introduction of extremely high forces, thereby enabling a much better exploitation of the existing lightweight construction potential of this material in comparison to other composite materials.Originality/value: Constantly rising demands on extremely stressed lightweight structures, particularly in traffic engineering as well as in machine building and plant engineering, increasingly require the use of endless fibre-reinforced composite materials which, due to their selectively adaptable characteristics profiles, are clearly superior to conventional monolithic materials.

  20. Considerations regarding the volume fraction influence on the wear behavior of the fiber reinforced composite systems

    Caliman, R.


    This paper contains an analysis of the factors that have an influence on the tribological characteristics of the composite material sintered with metal matrix reinforced with carbon fibers. These composites are used generally if it’s needed the wear resistant materials, whereas these composites have high specific strength in conjunction with a good corrosion resistance at low densities and some self-lubricating properties. Through the knowledge of the better tribological properties of the materials and their behavior to wear, can be generated by dry and the wet friction. Thus, where necessary the use of high temperature resistant material with low friction between the elements, carbon fiber composite materials are very suitable because they have: mechanical strength and good ductility, melting temperature on the higher values, higher electrical and thermal conductivity, lower wear speed and lower friction forces. For this purpose, this paper also contains an experimental program based on the evidence of formaldehyde resin made from fiber reinforced Cu-carbon with the aim to specifically determine the volume of fibers fraction for the consolidation of the composite material. In order to determine the friction coefficient and the wear rates of the various fiber reinforced polymer mixtures of carbon have been used special devices with needle-type with steel disc. These tests were conducted in the atmosphere at the room temperature without external lubrication study taking into consideration the sliding different speeds with constant loading task.

  1. Self-healing in single and multiple fiber(s) reinforced polymer composites


    You Polymer composites have been attractive medium to introduce the autonomic healing concept into modern day engineering materials. To date, there has been significant research in self-healing polymeric materials including several studies specifically in fiber reinforced polymers. Even though several methods have been suggested in autonomic healing materials, the concept of repair by bleeding of enclosed functional agents has garnered wide attention by the scientific community. A self-...

  2. Materials Characterisation of Glass/epoxy Composites - Focusing on Process Conditions

    Jakobsen, Johnny; Lyckegaard, Anders; Jensen, Erik Appel


    Predicting the behaviour of fibre reinforced polymer composites taking the process conditions into account involves advanced modelling techniques and an extensive materials characterisation. The materials characterisation of a chopped strand mat glass/epoxy composite has been the focus...

  3. Micromechanics of the Interface in Fibre-Reinforced Cement Materials

    Stang, Henrik; Shah, S.P.


    the strength and ductility of the brittlematrix material rather than changing the overall stiffness,the ability of the fibres to interact with cracking processes in thematrix material is essential. Furthermore, since matrix cracking in afibre reinforced material can only take place with simultaneousinterfacial...

  4. Shape distortions in fabric reinforced composite products due to processing induced fibre reorientation

    Lamers, Edwin Adriaan Derk


    Woven fabric reinforced composite materials are typically applied in plate or shell structures, such as ribs, stiffeners and skins. Products of these types can be produced with several production processes. A few examples are diaphragm forming, matched metal die forming and rubber press forming. Sha

  5. Shape distortions in fabric reinforced composite products due to processing induced fibre reorientation

    Lamers, E.A.D.


    Woven fabric reinforced composite materials are typically applied in plate or shell structures, such as ribs, stiffeners and skins. Products of these types can be produced with several production processes. A few examples are diaphragm forming, matched metal die forming and rubber press forming.

  6. Modeling of Self-Healing Polymer Composites Reinforced with Nanoporous Glass Fibers

    Privman, Vladimir; Dementsov, Alexander; Sokolov, Igor


    We report on our progress towards continuum rate equation modeling, as well as numerical simulations, of self-healing of fatigue in composites reinforced with glue carrying nanoporous fibers. We conclude that with the proper choice of the material parameters, effects of fatigue can be partially overcome and degradation of mechanical properties can be delayed.


    Shi Zhifei; Zhou Limin


    A new degradation function of the friction coefficient is used. Based on the double shear-lag model and Paris formula, the interfacial damage of coated fiber-reinforced composites under tension-tension cyclic loading is studied. The effects of strength and thickness of the coating materials on the debond stress, debond rate as well as debond length are simulated.

  8. A Micro Raman Investigation of Viscoelasticity in Short Fibre Reinforced Polymer Matrix Composites

    Schjødt-Thomsen, Jan

    The purpose of the present Ph.D. project is to investigate the load transfer mechanisms between the fibre and matrix and the stress/strain fields in and around single fibres in short fibre reinforced viscoelastic polymer matrix composites subjected to various loading histories. The materials...

  9. Agrofibre reinforced poly(lactic acid) composites: Effect of moisture on degradation and mechanical properties

    Oever, van den M.J.A.; Beck, B.; Müssig, J.


    Natural fibre reinforced PLA composites are a 100% biobased material with a promising mechanical properties profile. However, natural fibres are hygroscopic whereas PLA is sensitive to hydrolytic degradation under melt processing conditions in the presence of small amounts of water. Here, we determi

  10. Advanced composite materials and processes

    Baucom, Robert M.


    Composites are generally defined as two or more individual materials, which, when combined into a single material system, results in improved physical and/or mechanical properties. The freedom of choice of the starting components for composites allows the generation of materials that can be specifically tailored to meet a variety of applications. Advanced composites are described as a combination of high strength fibers and high performance polymer matrix materials. These advanced materials are required to permit future aircraft and spacecraft to perform in extended environments. Advanced composite precursor materials, processes for conversion of these materials to structures, and selected applications for composites are reviewed.

  11. NDE of Fiber Reinforced Foam Composite Structures for Future Aerospace Vehicles

    Walker, james; Roth, Don; Hopkins, Dale


    This slide presentation reviews the complexities of non-destructive evaluation (NDE) of fiber reinforced foam composite structures to be used for aerospace vehicles in the future.Various views of fiber reinforced foam materials are shown and described. Conventional methods of NDE for composites are reviewed such as Micro-computed X-Ray Tomography, Thermography, Shearography, and Phased Array Ultrasonics (PAUT). These meth0ods appear to work well on the face sheet and face sheet ot core bond, they do not provide adequate coverage for the webs. There is a need for additional methods that will examine the webs and web to foam core bond.

  12. Modeling and mesoscopic damage constitutive relation of brittle short-fiber-reinforced composites

    刘洪秋; 梁乃刚; 夏蒙棼


    Aimed at brittle composites reinforced by randomly distributed short-fibers with a relatively large aspect ratio, stiffness modulus and strength, a mesoscopic material model was proposed. Based on the statistical description,damage mechanisms, damage-induced anisotropy, damage rate effect and stress redistribution, the constitutive relation were derived. By taking glass fiber reinforced polypropylene polymers as an example, the effect of initial orientation distribution of fibers, damage-induced anisotropy, and damage-rate effect on macro-behaviors of composites were quantitatively analyzed. The theoretical predictions compared favorably with the experimental results.

  13. Friction Joint Between Basalt-Reinforced Composite and Aluminum

    Costache, Andrei; Glejbøl, Kristian; Sivebæk, Ion Marius


    The purpose of this study was to anchor basalt-reinforced polymers in an aluminum grip using dry friction. Dry friction clamping is considered the optimal solution for post-mounting of load-bearing terminations on composite structures. A new test method is presented for characterizing the frictio......The purpose of this study was to anchor basalt-reinforced polymers in an aluminum grip using dry friction. Dry friction clamping is considered the optimal solution for post-mounting of load-bearing terminations on composite structures. A new test method is presented for characterizing...

  14. Fatigue damage propagation in unidirectional glass fibre reinforced composites

    Hansen, Jens Zangenberg; Alzamora Guzman, Vladimir Joel; Østergaard, R.C.


    Damage progression in unidirectional glass fibre reinforced composites exposed to tension fatigue is investigated, and a quantitative explanation is given for the observed stiffness loss. The stiffness degradation during fatigue is directly related to fibre breaks in the load-carrying axial fibre...... needs further attention and understanding in order to improve the fatigue life-time of glass fibre reinforced composites....... bundles. The underlying mechanisms are examined using digital microscopy, and it is postulated that fatigue damage initiates due to stress concentrations between the backing (transverse) layer and the unidirectional layer, followed by a cyclic fretting and axial fibre debonding. This fretting mechanism...

  15. Epoxy-based carbon nanotubes reinforced composites

    Kesavan Pillai, Sreejarani


    Full Text Available blocks for 24 h at 60?C. Low and high magnification transmission electron microscopy (TEM) images of the thin slices cut from the composite showed that the thinner and longer nanotubes were preferentially oriented along the cutting direction, though... in Epon 828 epoxy resin matrix. The composites were cured with triethylene tetraamine hardener by gelling overnight at room temperature (RT) and curing at 100?C for 2 h. The micro-structural analysis of the composite using scanning electron microscopy...




    Full Text Available The use of Fibre Reinforced Polimer (FRP materials for the repair and strengthening of Reinforced Concrete structures has become widespread recently. FRP materials are being prefered because they have very high tensile strength, resistance to corrosion and they do not affect the use of the building during the repair and strengthening process. Four reinfoced concrete beams repaired and strengthened with FRP materials have been used in this study which were performed at Pamukkale University-Faculty of Engineering- Civil Engineering Department- Structural Engineering Laboratuary. The behaviour of the beams before and after repair and strengthening was compared by obtaining the load- displacement curves under static loading. In this study, it was observed that the repair and strengthening of reinforced concrete beams by using FRP materials had increased the load carrying capacity significantly.

  17. Effect of Sodium bicarbonate on Fire behaviour of tilled E- Glass Reinforced Epoxy Composites

    Girish, S.; Devendra, K.; Bharath, K. N.


    Composites such as fibre reinforced polymers give us the good mechanical properties, but their fire behaviour is not appreciable and needs to be improved. In this work, E- glass fiber is used as a reinforcement material and Epoxy resin is used as a matrix with particulate sodium bi-carbonate (NaHCO3) is used as additive. The hand lay-up technique is adopted for the development of composites by varying percentage of additive. All the tests were conducted according to ASTM standards to study the Fire behaviour of the developed composites. The different fire properties like Ignition time, mass loss rate and flame propagation rate of Fiber Reinforced Polymers (FRP) with NaHCO3 are compared with neat FRPs. It is found that the ignition time increases as the percentage of additive is increased.

  18. Dynamic Effects in Elastothermodynamic Damping of Hollow Particle Reinforced Metal-Matrix Composites

    Srivastava, Sunil Kumar; Mishra, Bhanu Kumar


    The Metal-Matrix Composites (MMCs) containing hollow spherical reinforcements are under active development for the applications such as space structures, submarine hulls etc. where weight is of critical importance. When these materials are subjected to a time varying strain field, energy is dissipated because of the thermoelastic effect (Elastothermodynamic Damping or ETD). The quasi-static ETD analysis for the MMCs containing hollow spherical particles has been reported in literature. The entropic approach, which is better suited for composite materials with perfect or imperfect interfaces, is used for the analysis. In the present work, the effect of inertia forces is carried out on ETD of hollow particle-reinforced MMCs. For given particle volume fractions (V p ), the inertia forces are found to be more significant at higher value of thermal parameter (Ω T1) (alternatively, frequency of vibration if reinforcement radius is fixed), large cavity volume fraction (V h ) and low value of the parameter B1.

  19. Parametric Analysis of Composite Reinforced Wood Tubes Under Axial Compression

    Cabrero, J.; Heiduschke, A.; Haller, P. (P.)


    Wood tubes combine economy, an efficient use of the material and optimal structural performance. They can be optionally reinforced with technical fibers and/or textiles laminated to the outer wood surface. The paper presents the outcomes of a parametric study on the performance of wood reinforced tubes submitted to axial compression. Simple analytical models were applied to estimate the load-carrying capacity of the tubes and their failure mechanisms. Analytical and numerical models were deve...




    Full Text Available This paper based on bidirectional and short carbon fiber reinforced epoxy composites reports the effect of fiber loading on physical, mechanical and thermo-mechanical properties respectively. The five different fiber loading, i.e., 10wt. %, 20wt. %, 30wt. %, 40wt. % and 50wt. % were taken for evaluating the above said properties. The physical and mechanical properties, i.e., hardness, tensile strength, flexural strength, inter-laminar shear strength and impact strength are determined to represent the behaviour of composite structures with that of fiber loading. Thermo-mechanical properties of the material are measured with the help of Dynamic Mechanical Analyser to measure the damping capacity of the material that is used to reduce the vibrations. The effect of storage modulus, loss modulus and tan delta with temperature are determined. Finally, Cole–Cole analysis is performed on both bidirectional and short carbon fiber reinforced epoxy composites to distinguish the material properties of either homogeneous or heterogeneous materials. The results show that with the increase in fiber loading the mechanical properties of bidirectional carbon fiber reinforced epoxy composites increases as compared to short carbon fiber reinforced epoxy composites except in case of hardness, short carbon fiber reinforced composites shows better results. Similarly, as far as Loss modulus, storage modulus is concerned bidirectional carbon fiber shows better damping behaviour than short carbon fiber reinforced composites.

  1. Effects of Fiber Reinforcement on Clay Aerogel Composites

    Katherine A. Finlay


    Full Text Available Novel, low density structures which combine biologically-based fibers with clay aerogels are produced in an environmentally benign manner using water as solvent, and no additional processing chemicals. Three different reinforcing fibers, silk, soy silk, and hemp, are evaluated in combination with poly(vinyl alcohol matrix polymer combined with montmorillonite clay. The mechanical properties of the aerogels are demonstrated to increase with reinforcing fiber length, in each case limited by a critical fiber length, beyond which mechanical properties decline due to maldistribution of filler, and disruption of the aerogel structure. Rather than the classical model for reinforced composite properties, the chemical compatibility of reinforcing fibers with the polymer/clay matrix dominated mechanical performance, along with the tendencies of the fibers to kink under compression.

  2. Debonding failure and size effects in micro reinforced composites

    Legarth, Brian Nyvang; Niordson, Christian Frithiof


    Failure in micro-reinforced composites is investigated numerically using the strain-gradient plasticity theory of Gudmundson [Gudmundson, P., 2004. A unified treatment of strain gradient plasticity. Journal of the Mechanics and Physics of Solids 52 (6) 1379–1406] in a plane strain visco......-plastic formulation. Bi-axially loaded unit cells are used and failure is modeled using a cohesive zone at the reinforcement interface. During debonding a sudden stress drop in the overall average stress–strain response is observed. Adaptive higher-order boundary conditions are imposed at the reinforcement interface...... for realistically modeling the restrictions on moving dislocations as debonding occurs. It is found that the influence of the imposed higher-order boundary conditions at the interface is minor. If strain-gradient effects are accounted for a void with a smooth shape develops at the reinforcement interface while...

  3. Failure Modes in Composite Materials.


    Derek, An Introduction to Composite Materials , New York: Cambridge University Press, 1981. 12. Jamison, R. D., Mechanical Engineering Department...1978. 19. Tsai, Stephen W., Introduction to Composite Materials , Lancaster, Pennsylvania: Technomic Publishing Company, Inc., 1980. 4,’ * .20. Vernon

  4. Micromechanics Fatigue Damage Analysis Modeling for Fabric Reinforced Ceramic Matrix Composites

    Min, J. B.; Xue, D.; Shi, Y.


    A micromechanics analysis modeling method was developed to analyze the damage progression and fatigue failure of fabric reinforced composite structures, especially for the brittle ceramic matrix material composites. A repeating unit cell concept of fabric reinforced composites was used to represent the global composite structure. The thermal and mechanical properties of the repeating unit cell were considered as the same as those of the global composite structure. The three-phase micromechanics, the shear-lag, and the continuum fracture mechanics models were integrated with a statistical model in the repeating unit cell to predict the progressive damages and fatigue life of the composite structures. The global structure failure was defined as the loss of loading capability of the repeating unit cell, which depends on the stiffness reduction due to material slice failures and nonlinear material properties in the repeating unit cell. The present methodology is demonstrated with the analysis results evaluated through the experimental test performed with carbon fiber reinforced silicon carbide matrix plain weave composite specimens.

  5. Microstructure and hardness of WC-Co particle reinforced iron matrix surface composite

    Zhang Peng


    Full Text Available In this study, a high Cr cast iron surface composite material reinforced with WC-Co particles 2-6 mm in size was prepared using a pressureless sand mold infiltration casting technique. The composition, microstructure and hardness were determined by means of energy dispersive spectrometry (EDS, electron probe microanalysis (EPMA, scanning electron microscope (SEM and Rockwell hardness measurements. It is determined that the obtained composite layer is about 15 mm thick with a WC-Co particle volumetric fraction of ~38%. During solidification, interface reaction takes place between WC-Co particles and high chromium cast iron. Melting and dissolving of prefabricated particles are also found, suggesting that local Co melting and diffusion play an important role in promoting interface metallurgical bonding. The composite layer is composed of ferrite and a series of carbides, such as (Cr, W, Fe23C6, WC, W2C, M6C and M12C. The inhomogeneous hardness in the obtained composite material shows a gradient decrease from the particle reinforced metal matrix composite layer to the matrix layer. The maximum hardness of 86.3 HRA (69.5 HRC is obtained on the particle reinforced surface, strongly indicating that the composite can be used as wear resistant material.

  6. Further development of the tungsten-fibre reinforced tungsten composite

    Gietl, Hanns; Hoeschen, Till; Riesch, Johann [Max-Planck-Institut fuer Plasmaphysik, 85748 Garching (Germany); Aumann, Martin; Coenen, Jan [Forschungszentrum Juelich, IEK4, 52425 Juelich (Germany); Huber, Philipp [Lehrstuhl fuer Textilmaschinenbau und Institut fuer Textiltechnik (ITA), 52062 Aachen (Germany); Neu, Rudolf [Max-Planck-Institut fuer Plasmaphysik, 85748 Garching (Germany); Technische Universitaet Muenchen, 85748 Garching (Germany)


    For the use in a fusion device tungsten has a unique property combination. The brittleness below the ductile-to-brittle transition temperature and the embrittlement during operation e.g. by overheating, neutron irradiation are the main drawbacks for the use of pure tungsten. Tungsten fibre-reinforced tungsten composites utilize extrinsic mechanisms to improve the toughness. After proofing that this idea works in principle the next step is the conceptual proof for the applicability in fusion reactors. This will be done by producing mock-ups and testing them in cyclic high heat load tests. For this step all constituents of the composite, which are fibre, matrix and interface, and all process steps need to be investigated. Tungsten fibres are investigated by means of tension tests to find the optimum diameter and pretreatment. New interface concepts are investigated to meet the requirements in a fusion reactor, e.g. high thermal conductivity, low activation. In addition weaving processes are evaluated for their use in the fibre preform production. This development is accompanied by an extensive investigation of the materials properties e.g. single fibre tension tests.

  7. Manufacture of magnetically active fiber-reinforced composites for use in power generation

    Etches, Julie; Bond, Ian; Mellor, Phil


    A major issue yet to be resolved for embedding sensors, actuators and microelectromechanical systems (MEMS) in 'smart' structures is that of providing power. Work is ongoing in the field with examples of micro battery technology, use of solar power and micro fuel cells. The work presented here considers a technology to enable the development of integrated power generation and actuation. Magnetic fibre reinforced composite material has been developed which utilises hollow glass fibres filled with active magnetic material. The resulting material maintains structural integrity as well as providing a possible means of electrical power generation from a dynamically loaded structure. The hollow glass fibres were manufactured in-house using a bespoke fibre drawing facility. Hard magnetic powder materials were introduced into the hollow fibre cores to provide an active electromagnetic function. This paper will discuss the manufacture, characterization and optimisation of active magnetic fibre reinforced composite materials.

  8. Hardness and wear resistance of carbon nanotube reinforced aluminum-copper matrix composites.

    Nam, Dong Hoon; Kim, Jae Hwang; Cha, Seung Il; Jung, Seung Il; Lee, Jong Kook; Park, Hoon Mo; Park, Hyun Dal; Hong, Hyung


    Recently, carbon nanotubes (CNTs) have been attracted to reinforcement of composite materials due to their extraordinary mechanical, thermal and electrical properties. Many researchers have attempted to develop CNT reinforced metal composites with various fabrication methods and have shown possibilities for structural and functional applications. Among them, CNT reinforced Al matrix composites have become very attractive due to their huge structural application in industry. In this study, CNT reinforced Al-Cu matrix composites with a microstructure of homogeneous dispersion of CNTs in the Al-Cu matrix are investigated. The CNT/Al-Cu composites are fabricated by mixing of CNT/Cu composite powders and Al powders by high energy ball mill process followed by hot extrusion process. The hardness and wear resistance of the CNT/Al-Cu composites are enhanced by 1.4 and 3 times, respectively, compared to those values for the Al-Cu matrix. This remarkable enhancement mainly originates from the homogeneous dispersion of CNTs in Al-Cu matrix and self-lubricant effect of CNTs.

  9. Advanced composite materials for optomechanical systems

    Zweben, Carl


    Polymer matrix composites (PMCs) have been well established in optomechanical systems for several decades. The other three classes of composites; metal matrix composites (MMCs), ceramic matrix composites (CMCs), and carbon matrix composites (CAMCs) are making significant inroads. The latter include carbon/carbon (C/C) composites (CCCs). The success of composites has resulted in increasing use in consumer, industrial, scientific, and aerospace/defense optomechanical applications. Composites offer significant advantages over traditional materials, including high stiffnesses and strengths, near-zero and tailorable coefficients of thermal expansion (CTEs), tailorable thermal conductivities (from very low to over twice that of copper), and low densities. In addition, they lack beryllium's toxicity problems. Some manufacturing processes allow parts consolidation, reducing machining and joining operations. At present, PMCs are the most widely used composites. Optomechanical applications date from the 1970s. The second High Energy Astrophysical Observatory spacecraft, placed in orbit in 1978, had an ultrahigh-modulus carbon fiber-reinforced epoxy (carbon/epoxy) optical bench metering structure. Since then, fibers and matrix materials have advanced significantly, and use of carbon fiber-reinforced polymers (CFRPs) has increased steadily. Space system examples include the Hubble Space Telescope metering truss and instrument benches, Upper Atmosphere Research Satellite (UARS), James Webb Space Telescope and many others. Use has spread to airborne applications, such as SOFIA. Perhaps the most impressive CFRP applications are the fifty-four 12m and twelve 7m moveable ground-based ALMA antennas. The other three classes of composites have a number of significant advantages over PMCs, including no moisture absorption or outgassing of organic compounds. CCC and CMC components have flown on a variety of spacecraft. MMCs have been used in space, aircraft, military and industrial

  10. Study on the Compatibility of SMA and Composite Materials by Holographic Interferometry

    ZHAO Zhimin


    With the help of holographic interferometry a study is conducted on the compatibility of SMA (shape memory alloy) and epoxy resin composite material. The paper gives experiment results and analysis which show that after coupling SMA with the composite material, the flexural rigidity of composite material is somewhat reinforced. Under certain conditions, SMA and the epoxy resin composite material are compatible.

  11. Study the Effect of Different Reinforcements on the Damping Properties of the Polymer Matrix Composite

    Mustafa Ziyara Shamukh


    Full Text Available In this research, damping properties for composite materials were evaluated using logarithmic decrement method to study the effect of reinforcements on the damping ratio of the epoxy matrix. Three stages of composites were prepared in this research. The first stage included preparing binary blends of epoxy (EP and different weight percentages of polysulfide rubber (PSR (0%, 2.5%, 5%, 7.5% and 10%. It was found that the weight percentage 5% of polysulfide was the best percentage, which gives the best mechanical properties for the blend matrix. The advantage of this blend matrix is that; it mediates between the brittle properties of epoxy and the flexible properties of a blend matrix with the highest percentage of PSR. The second stage included reinforcing the best blend matrix of epoxy-polysulfide (the blend matrix with the best percentage of polysulfide resulted from the previous stage, by different volume percentages of short fibers (Carbon& Glass separately and randomly. The volume percentages of fibers were (2.5%, 5%, 7.5%, and 10%. The third stage included reinforcing the blend composites with highest percentages of carbon and glass fiber, by different weight percentages of nano-particles (Red mud& Fly ash separately. The weight percentages of particles were (0.5%, 1%, 1.5%, and 2%. The experimental results showed that blending polysulfide rubber with epoxy increased the damping ratio. As for reinforcement materials, they decreased the damping ratio, where glass fiber composites have significantly higher damping ratio than other composites.

  12. Seamless metal-clad fiber-reinforced organic matrix composite structures and process for their manufacture

    Bluck, Raymond M. (Inventor); Bush, Harold G. (Inventor); Johnson, Robert R. (Inventor)


    A metallic outer sleeve is provided which is capable of enveloping a hollow metallic inner member having continuous reinforcing fibers attached to the distal end thereof. The inner member is then introduced into outer sleeve until inner member is completely enveloped by outer sleeve. A liquid matrix member is then injected into space between inner member and outer sleeve. A pressurized heat transfer medium is flowed through the inside of inner member, thereby forming a fiber reinforced matrix composite material. The wall thicknesses of both inner member and outer sleeve are then reduced to the appropriate size by chemical etching, to adjust the thermal expansion coefficient of the metal-clad composite structure to the desired value. thereby forming a fiber reinforced matrix composite material. The wall thicknesses of both inner member and outer sleeve are then reduced to the appropriate size by chemical etching, to adjust the thermal expansion coefficient of the metal-clad composite structure to the desired value. The novelty of this invention resides in the development of a efficient method of producing seamless metal clad fiber reinforced organic matrix composite structures.

  13. Fabrication and evaluation of mechanical properties of alkaline treated sisal/hemp fiber reinforced hybrid composite

    Venkatesha Gupta, N. S.; Akash; Sreenivasa Rao, K. V.; kumar, D. S. Arun


    Fiber reinforced polymer composite have acquired a dominant place in variety of applications because of higher specific strength and modulus, the plant based natural fiber are partially replacing currently used synthetic fiber as reinforcement for polymer composites. In this research work going to develop a new material which posses a strength to weight ratio that for exceed any of the present material. The hybrid composite sisal/hemp reinforced with epoxy matrix has been developed by compression moulding technique according to ASTM standards. Sodium hydroxide (NAOH) was used as alkali for treating the fibers. The amount of reinforcement was varied from 10% to 50% in steps of 10%. Prepared specimens were examined for mechanical properties such as tensile strength, flexural strength, and hardness. Hybrid composite with 40wt% sisal/hemp fiber were found to posses higher strength (tensile strength = 53.13Mpa and flexural strength = 82.07Mpa) among the fabricated hybrid composite specimens. Hardness value increases with increasing the fiber volume. Morphological examinations are carried out to analyze the interfacial characteristics, internal structure and fractured surfaces by using scanning electron microscope.


    Oliver Wirjadi


    Full Text Available Fibre reinforced composites constitute a relevant class of materials used chiefly in lightweight constructions for example in fuselages or car bodies. The spatial arrangement of the fibres and in particular their direction distribution have huge impact on macroscopic properties and, thus, its determination is an important topic of material characterisation. The fibre direction distribution is defined on the unit sphere, and it is therefore preferable to work with fully three-dimensional images of the microstructure as obtained, e.g., by computed micro-tomography. A number of recent image analysis algorithms exploit local grey value variations to estimate a preferred direction in each fibre point. Averaging these local results leads estimates of the volume-weighted fibre direction distribution. We show how the thus derived fibre direction distribution is related to quantities commonly used in engineering applications. Furthermore, we discuss four algorithms for local orientation analysis, namely those based on the response of anisotropic Gaussian filters, moments and axes of inertia derived from directed distance transforms, the structure tensor, or the Hessian matrix. Finally, the feasibility of these algorithms is demonstrated for application examples and some advantages and disadvantages of the underlying methods are pointed out.

  15. Fractography and Mechanical Properties of Urethane Dimethacrylate Dental Composites Reinforced with Glass Nanoparticles

    Monfared M; Bahrololoom ME


    Statement of Problem: Dental resin composites are becoming prevalent in restorative dentistry and have almost replaced amalgam nowadays. Consequently, their mechanical properties and durability are critical. Objectives: The aim of this study was to produce Pyrex glass nano-particles by wet milling process and use them as reinforcement in dental resins for anterior restorations and then examination of fractographic properties of these composites. Materials and Methods: The glass nano-par...


    张少琴; 杨维阳


    A newly developed Z fracture criterion for the composite materials was introduced,the new concepts of in-plane average strain,in-plane dilatational strain energy density factor and reciprocal characteristic function were presented.Many experimental results show that the Z fracture criterion can be well used to predict the crack propagating direction for mode Ⅰ crack in carbon-fiber reinforced composite laminates.

  17. An Expert System in FRP Composite Material Design


    An expert system prototype for fibre-reinforced plastic matrix (FRP) composite material design,ESFRP, has been developed. The system consists of seven main functional parts: a general inference engine, a set of knowledge bases, a material properties algorithm base, an explanation engine, various data bases, several function models and the user interface. The ESFRP can simulate human experts to make design scheme for fibre-reinforced plastics design, FRP layered plates design and FRP typical engineering components design. It can also predict the material properties and make strength analysis according to the micro and macro mechanics of composite materials. A satisfied result can be gained through the reiterative design.

  18. Studies on natural fiber reinforced polymer matrix composites

    Patel, R. H.; Kapatel, P. M.; Machchhar, A. D.; Kapatel, Y. A.


    Natural fiber reinforced composites show increasing importance in day to days applications because of their low cost, lightweight, easy availability, non-toxicity, biodegradability and environment friendly nature. But these fibers are hydrophilic in nature. Thus they have very low reactivity and poor compatibility with polymers. To overcome these limitations chemical modifications of the fibers have been carried out. Therefore, in the present work jute fibers have chemically modified by treating with sodium hydroxide (NaOH) solutions. These treated jute fibers have been used to fabricate jute fiber reinforced epoxy composites. Mechanical properties like tensile strength, flexural strength and impact strength have been found out. Alkali treated composites show better properties compare to untreated composites.

  19. Microstructural study of aluminium-matrix composites reinforced with SiC

    Velhinho, A.; Braz Fernandes, F.M.; Botas, J.D. [CENIMAT, Centro de Investigacao de Materiais, Caparica (Portugal)


    Rheocasting, as a semi-solid process, allows the production of aluminium matrix composites at relatively low temperatures (ca. 580 C), thus favouring a reduced reactivity at the reinforcement-metal matrix interface. When one considers the possibility of further processing (such as any treatment involving remelting, even if partial) of the material, this trait allows a more rigorous control of the interfaces. Composite samples have been produced using as matrix an Al7Si-0.3Mg alloy reinforced with SiC{sub p} (granulometry: 120 {mu}m; V{sub r}=0.30). These were rheocast at 583 C, followed by compression and subsequent water-quenching. A structural characterisation (optical microscopy and XRD) of the as-received matrix material, as well as of the reinforced and non-reinforced rheocast material was performed. The phases identification will provide a basis for the understanding of the further processing where the rheocast material will be used as a precursor to produce functionally graded metal-matrix composites by centrifugal casting. (orig.)

  20. Mechanical Spectroscopy of Nanostructured Composite Materials

    Mari, Daniele; Schaller, Robert; Mazaheri, Mehdi, E-mail: [Ecole Polytechnique Federale de Lausanne, Laboratoire de Physique de la Matiere Complexe, Groupe de Spectroscopie Mecanique, CH-1015 Lausanne (Switzerland)


    The thermo-mechanical behavior of different nano-structured composite materials, which were processed within the SAPHIR European Integrated Project, has been characterized by mechanical spectroscopy. The obtained results show clearly that creep resistance of fine grain ceramics such as zirconia can be improved by carbon nano-tube (CNT) reinforcements. On the other hand the elastic modulus and the damping capacity of aluminum matrix composites were increased by SiC nano-particle additions. It has also been observed that CNT additions are responsible for a better thermal stability of polymer such as ABS (Acrylonitrile-Butadiene-Styrene) used in automotive industry.

  1. Doubly curved nanofiber-reinforced optically transparent composites

    Shams, Md. Iftekhar; Yano, Hiroyuki


    Doubly curved nanofiber-reinforced optically transparent composites with low thermal expansion of 15 ppm/k are prepared by hot pressing vacuum-filtered Pickering emulsions of hydrophobic acrylic resin monomer, hydrophilic chitin nanofibers and water. The coalescence of acrylic monomer droplets in the emulsion is prevented by the chitin nanofibers network. This transparent composite has 3D shape moldability, making it attractive for optical precision parts.

  2. Flexural Properties of WeftKnitted Fabric Reinforced Composites

    龙海如; 冯勋伟


    Several different kinds of weft knitted fabrics from glass fiber yarns were used as reinforcement to make fabric/polyester composite laminates. Flexural tests were carried out to examine stress- deflection process and compare the mechanical properties in course and wale directions of these composites. The experimental results indicate that the numbers of load-bearing yarn in course and wale direction and the fabric density are the main factors influencing the ultimate tensile strength and initial elastic modulus of specimens.

  3. Tensile Properties of Weft Knitted Fabric Reinforced Composites



    Seven kinds of weft knitted fabrics from glass fiber yarns were used as reinforcement to make fabric/epoxy composite laminates. Tensile tests were carried out to examine and compare the mechanical properties in course and wale direction of these composites. On the basis of experimental results, attempts have been made to analyze some main factors influencing stress-strain curve, ultimate tensile strength and initial elastic modulus of specimens.

  4. Processing of thermo-structural carbon-fiber reinforced carbon composites

    Luiz Cláudio Pardini


    Full Text Available The present work describes the processes used to obtain thermostructural Carbon/Carbon composites. The processing of these materials begins with the definition of the architecture of the carbon fiber reinforcement, in the form of stacked plies or in the form of fabrics or multidirectional reinforcement. Incorporating fiber reinforcement into the carbon matrix, by filling the voids and interstices, leads to the densification of the material and a continuous increase in density. There are two principal processing routes for obtaining these materials: liquid phase processing and gas phase processing. In both cases, thermal processes lead to the formation of a carbon matrix with specific properties related to their precursor. These processes also differ in terms of yield. With liquid phase impregnation the yield is around 45 per cent, while gas phase processing yields around 15 per cent.

  5. Exposure Assessment of Particulate Matter from Abrasive Treatment of Carbon and Glass Fibre-Reinforced Epoxy-Composites

    Jensen, Alexander C. Ø.; Levin, Marcus; Koivisto, Antti J.


    The use of composites is ever increasing due to their important structural and chemical features. The composite component production often involves high energy grinding and sanding processes to which emissions workers are potentially exposed. In this study we investigated the machining of carbon...... and glass fibre-reinforced epoxy composite materials at two facilities. We measured particle number concentrations and size distributions of the released material in near field and far field during sanding of glass-and carbon fibre-reinforced composites. We assessed the means of reducing exposure during...

  6. Mechanical properties of kenaf bast and core fibre reinforced unsaturated polyester composites

    Ishak, M R; Leman, Z; Sapuan, S M [Department of Mechanical and Manufacturing Engineering, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Edeerozey, A M M; Othman, I S, E-mail: [Faculty of Manufacturing Engineering, Universiti Teknikal Malaysia Melaka, 76109 Durian Tunggal, Melaka (Malaysia)


    Kenaf fibre has high potential to be used for composite reinforcement in biocomposite material. It is made up of an inner woody core and an outer fibrous bark surrounding the core. The aim of this study was to compare the mechanical properties of short kenaf bast and core fibre reinforced unsaturated polyester composites with varying fibre weight fraction i.e. 0%, 5%, 10%, 20%, 30% and 40%. The compression moulding technique was used to prepare the composite specimens for tensile, flexural and impact tests in accordance to the ASTM D5083, ASTM D790 and ASTM D256 respectively. The overall results showed that the composites reinforced with kenaf bast fibre had higher mechanical properties than kenaf core fibre composites. The results also showed that the optimum fibre content for achieving highest tensile strength for both bast and core fibre composites was 20%wt. It was also observed that the elongation at break for both composites decreased as the fibre content increased. For the flexural strength, the optimum fibre content for both composites was 10%wt while for impact strength, it was at 10%wt and 5%wt for bast and core fibre composites respectively.

  7. Study of variation of thermal diffusivity of advanced composite materials of E-glass fibre reinforced plastic (GFRP) in temperature range 5–300 K

    Kalobaran Das; S M Kamaruzzaman; Tapas Ranjan Middya; Siddhartha Datta


    Modified Angstrom method is applied to study the variation of thermal diffusivity of plain woven fabric composite in closed cycle cryo-refrigerator (CCR) based set up in the temperature range 5–300 K. The set up used is plug in type and its small size offers portability. The set up works without use of any liquid cryogen. The temperature versus thermal diffusivity curve shows three distinct regions viz. 5–30 K, 30–120 K and 120–300 K. In the first region thermal diffusivity varies exponentially and rapidly. In the second region thermal diffusivity changes exponentially but relatively slowly than that in the first region. In the last region the change in thermal diffusivity with temperature is exponential in nature but very slow.

  8. Optimisation of Fabric Reinforced Polymer Composites Using a Variant of Genetic Algorithm

    Axinte, Andrei; Taranu, Nicolae; Bejan, Liliana; Hudisteanu, Iuliana


    Fabric reinforced polymeric composites are high performance materials with a rather complex fabric geometry. Therefore, modelling this type of material is a cumbersome task, especially when an efficient use is targeted. One of the most important issue of its design process is the optimisation of the individual laminae and of the laminated structure as a whole. In order to do that, a parametric model of the material has been defined, emphasising the many geometric variables needed to be correlated in the complex process of optimisation. The input parameters involved in this work, include: widths or heights of the tows and the laminate stacking sequence, which are discrete variables, while the gaps between adjacent tows and the height of the neat matrix are continuous variables. This work is one of the first attempts of using a Genetic Algorithm (GA) to optimise the geometrical parameters of satin reinforced multi-layer composites. Given the mixed type of the input parameters involved, an original software called SOMGA (Satin Optimisation with a Modified Genetic Algorithm) has been conceived and utilised in this work. The main goal is to find the best possible solution to the problem of designing a composite material which is able to withstand to a given set of external, in-plane, loads. The optimisation process has been performed using a fitness function which can analyse and compare mechanical behaviour of different fabric reinforced composites, the results being correlated with the ultimate strains, which demonstrate the efficiency of the composite structure.

  9. The assessment of metal fiber reinforced polymeric composites

    Chung, Wenchiang R.


    Because of their low cost, excellent electrical conductivity, high specific strength (strength/density), and high specific modulus (modulus/density) short metal fiber reinforced composites have enjoyed a widespread use in many critical applications such as automotive industry, aircraft manufacturing, national defense, and space technology. However, little data has been found in the study of short metal fibrous composites. Optimum fiber concentration in a resin matrix and fiber aspect ratio (length-to-diameter ratio) are often not available to a user. Stress concentration at short fiber ends is the other concern when the composite is applied to a load-bearing application. Fracture in such composites where the damage will be initiated or accumulated is usually difficult to be determined. An experimental investigation is therefore carefully designed and undertaken to systematically evaluate the mechanical properties as well as electrical properties. Inconel 601 (nickel based) metal fiber with a diameter of eight microns is used to reinforce commercially available thermoset polyester resin. Mechanical testing such as tensile, impact, and flexure tests along with electrical conductivity measurements is conducted to study the feasibility of using such composites. The advantages and limitations of applying chopped metal fiber reinforced polymeric composites are also discussed.

  10. An engineering analysis of penetration of metal ball into fibre-reinforced composite targets

    Yong-chi LI; Zhi-hai WANG; Xiao-jun WANG; Xiu-zhang HU


    An engineering analysis of computing the penetration problem of a steel ball penetrating into fibre-reinforced composite targets is presented. Assume the metal ball is a rigid body, and the composite target is a transversely isotropic elasto-plastic material. In the analysis, a spherical cavity dilatation model is incorporated in the cylindrical cavity penetration method. Simulation results based on the modified model are in good agreement with the results for 3-D Kevlar woven (3DKW) composite anti-penetration experiments. Effects of the target material parameters and impact parameters on the penetration problem are also studied.

  11. Application of the finite-element method to improve the quasi-exact reinforcement theory of fibrous polymeric composites

    Klasztorny, M.; Urbanski, A.


    In the paper, the WL quasi-exact reinforcement theory of fibrous polymeric composites is improved. An optimum compatibility condition related to the transverse shear problem for a unit cell, which brings solutions closest to reality, is derived. This condition is formulated in the form of a linear combination of maximum radial and circumferential displacements. Optimum coefficients of this combination are determined by comparing analytical and numerical solutions for a test specimen in the form of a rectangular thin plate, which is in a plane strain state and is subject to selected loading schemes. The analytic solutions are obtained for a homogenized material by using the WL reinforcement theory. The numerical solutions are found for an actual heterogeneous composite material by using the finite-element method, and they verify the WL reinforcement theory, in particular, the admissibility of Hill's assumption. An analysis performed for two composite materials shows that the improved WL reinforcement theory gives adequate displacement fields.

  12. Thermoforming continuous fiber-reinforced thermoplastic composites

    Wu, Xiang.


    In this research the forming process was first decomposed into basic deformation elements with simple geometries, and models were then developed for these elements. A series-parallel model was developed for predicting the upper and lower bounds of composite shear modulus at forming temperature based on the fiber content, fiber distribution, and matrix shear modulus. A shear-flexure model was proposed to describe the initial load-deflection behavior of thermoplastic composites in bending. A ply buckling model was developed which included the contributions from both a surface tension term and a ply buckling term.

  13. Review of Carbon Fiber Reinforced Polymer Reinforced Material in Concrete Structure

    Ayuddin Ayuddin


    Full Text Available Carbon Fiber Reinforced Polymer (FRP is a material that is lightweight, strong, anti-magnetic and corrosion resistant. This material can be used as an option to replace the steel material in concrete construction or as material to improve the strength of existing construction. CFRP is quite easy to be attached to the concrete structure and proved economically used as a material for repairing damaged structures and increase the resilience of structural beams, columns, bridges and other parts of the structure against earthquakes. CFRP materials can be shaped sheet to be attached to the concrete surface. Another reason is due to the use of CFRP has a higher ultimate strength and lower weight compared to steel reinforcement so that the handling is significantly easier. Through this paper suggests that CFRP materials can be applied to concrete structures, especially on concrete columns. Through the results of experiments conducted proved that the concrete columns externally wrapped with CFRP materials can increase the strength. This treatment is obtained after testing experiments on 130 mm diameter column with a height of 700 mm with concentric loading method to collapse. The experimental results indicate that a column is wrapped externally with CFRP materials can achieve a load capacity of 250 kN compared to the concrete columns externally without CFRP material which only reached 150 kN. If the column is given internally reinforcing steel and given externally CFRP materials can reach 270 kN. It shows that CFRP materials can be used for concrete structures can even replace reinforcing steel that has been widely used in building construction in Indonesia.

  14. Composite materials processing, applications, characterizations


    Composite materials are used as substitutions of metals/traditional materials in aerospace, automotive, civil, mechanical and other industries. The present book collects the current knowledge and recent developments in the characterization and application of composite materials. To this purpose the volume describes the outstanding properties of this class of advanced material which recommend it for various industrial applications.

  15. Niobium Carbide-Reinforced Al Matrix Composites Produced by High-Energy Ball Milling

    Travessa, Dilermando Nagle; Silva, Marina Judice; Cardoso, Kátia Regina


    Aluminum and its alloys are key materials for the transportation industry as they contribute to the development of lightweight structures. The dispersion of hard ceramic particles in the Al soft matrix can lead to a substantial strengthening effect, resulting in composite materials exhibiting interesting mechanical properties and inspiring their technological use in sectors like the automotive and aerospace industries. Powder metallurgy techniques are attractive to design metal matrix composites, achieving a homogeneous distribution of the reinforcement into the metal matrix. In this work, pure aluminum has been reinforced with particles of niobium carbide (NbC), an extremely hard and stable refractory ceramic. Its use as a reinforcing phase in metal matrix composites has not been deeply explored. Composite powders produced after different milling times, with 10 and 20 vol pct of NbC were produced by high-energy ball milling and characterized by scanning electron microscopy and by X-ray diffraction to establish a relationship between the milling time and size, morphology, and distribution of the particles in the composite powder. Subsequently, an Al/10 pct NbC composite powder was hot extruded into cylindrical bars. The strength of the obtained composite bars is comparable to the commercial high-strength, aeronautical-grade aluminum alloys.

  16. Physicochemical characterization of three fiber-reinforced epoxide-based composites for dental applications.

    Bonon, Anderson J; Weck, Marcus; Bonfante, Estevam A; Coelho, Paulo G


    Fiber-reinforced composite (FRC) biomedical materials are in contact with living tissues arising biocompatibility questions regarding their chemical composition. The hazards of materials such as Bisphenol A (BPA), phthalate and other monomers and composites present in FRC have been rationalized due to its potential toxicity since its detection in food, blood, and saliva. This study characterized the physicochemical properties and degradation profiles of three different epoxide-based materials intended for restorative dental applications. Characterization was accomplished by several methods including FTIR, Raman, Brunauer-Emmett-Teller (BET) Analysis, X-ray fluorescence spectroscopy, and degradation experiments. Physicochemical characterization revealed that although materials presented similar chemical composition, variations between them were more largely accounted by the different phase distribution than chemical composition.

  17. Composite Reinforcement using Boron Nitride Nanotubes


    ApprovedOMB No. 0704-0188 The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for...nitride nanotubes change with the presence of atomic oxygen were also carried out. 15.  SUBJECT TERMS Nanotubes, Boron Nitride, Composites, Theoretical

  18. Epoxy Nano-Reinforced Composite Systems


    phase, in addition to the bulk matrix and nanofiller phases. The suppression of Tg in nanofilled composites has been observed by other reseachers (13...drawback. As this technology advances, the nanofiller market should see large growth and cost reduction as these additives are successfully applied

  19. Reinforced Sisal Fiber with Ferric Nitrate Composites

    Asif Jehan


    Full Text Available Ferric oxide synthesized through annealing route. The present research work deals with ferrite composite prepared using chemical reactions. Ferric nitrates and ammonium chloride doped with sisal fiber has been prepared. The structural behavior of aluminum oxide was studied in XRD, SEM, TEM, FTIR & dielectric measurement. This behavior showed ferrite nature of the sample.

  20. Effect of silane activation on shear bond strength of fiber-reinforced composite post to resin cement

    Kim, Hyun-Dong; Lee, Joo-Hee; Ahn, Kang-Min; Kim, Hee-Sun; Cha, Hyun-Suk


    PURPOSE Among the surface treatment methods suggested to enhance the adhesion of resin cement to fiber-reinforced composite posts, conflicting results have been obtained with silanization. In this study, the effects of silanization, heat activation after silanization, on the bond strength between fiber-reinforced composite post and resin cement were determined. MATERIALS AND METHODS Six groups (n=7) were established to evaluate two types of fiber post (FRC Postec Plus, D.T. Light Post) and th...

  1. Morphological, thermal and optical studies of jute-reinforced PbSrCaCuO-polypropylene composite

    Jacob, Reenu; Isac, Jayakumari


    New research with modern technologies has always grabbed substantial attention. Conservation of raw materials like natural fibers has helped composite world to explore eco-friendly components. The aim of this paper is to study the potential of jute fiber-reinforced ceramic polymers. Alkali-treated jute fiber has been incorporated in a polypropylene ceramic matrix at different volume fractions. The morphological, thermal and optical studies of jute-reinforced ceramic Pb2Sr2CaCu2O9 (PbSrCaCuO) are studied. Morphological results evidently demonstrate that when the polypropylene ceramic matrix is reinforced with jute fiber, interfacial interaction between the varying proportions of the jute fiber and ceramic composite takes place. TGA and DSC results confirm the enhancement in the thermal stability of ceramic composites reinforced with jute fiber. The UV analysis of the composite gives a good quality measure on the optical properties of the new composite prepared.


    A. V. Visnap


    Full Text Available From the analysis of a range of energy-saving materials used in the construction, it follows that the properties of fibropenobetona allow to expand the range of products from cellular concrete. At present, therefore become topical study on the applicability of composite rod reinforcement to ensure the operational reliability of building products, working in tension and bending under the condition of reducing their consumption of materials.

  3. Sol-gel coatings as active barriers to protect ceramic reinforcement in aluminum matrix composites

    Rams, J.; Urena, A.; Campo, M. [Departamento de Tecnologia Quimica, Ambiental y de los Materiales, ESCET, Universidad Rey Juan Carlos C/ Tulipan s/nMostoles 28933 Madrid (Spain)


    Silica obtained through a sol-gel process is used as a coating for ceramic reinforcements (SiC) in aluminium matrix composite materials. The interaction between molten aluminium and the coated particles during material casting can be controlled by means of the thermal treatment given to the coating. Wettability is increased because the coating reacts with molten aluminium, and the formation of the degrading aluminium carbide is inhibited. (Abstract Copyright [2004], Wiley Periodicals, Inc.)

  4. Coupling of plasticity and damage in glass fibre reinforced polymer composites

    Osnes H.


    Full Text Available This study addresses the nonlinear stress-strain response in glass fibre reinforced polymer composite laminates. Loading and unloading of these laminates indicate that the nonlinear response is caused by both damage and plasticity. A user defined material model is implemented in the finite element code LS-DYNA. The damage evolution is based on the Puck failure criterion [1], and the plastic behaviour is based on the quadratic Hill yield criterion for anisotropic materials [2].

  5. Processing and Performance of Alumina Fiber Reinforced Alumina Composites

    P.Y.Lee; T.Uchijima; T.Yano


    Processing of alumina fiber-reinforced alumina matrix composites by hot-pressing was described. The mechanical properties of the composites fabricated by different sintering conditions including temperature and pressure have been investigated. The results indicated that the higher sintering temperature and pressure corresponded to the higher bulk density and higher maximum strength of the composite, whereas the pseudo-ductility of the composite was lower. The preliminary results of the composite with monazite-coated fibers showed that maximum strength could be improved up to 35% compared with the noncoated fiber composite in the same sintering condition. Moreover, the fracture behavior of the composite changed from completely brittle fracture to non-brittle fracture under the suitable sintering conditions. SEM observation of the fracture surface indicated that the coating worked as a protective barrier and avoided sintering of the fibers together even at high temperature and pressure during densification process.

  6. Performance of Potassium Titanate Whisker Reinforced PPESK Composites

    Minjie QU; Xigao JIAN; Wei HE; Gongxiong LIAO


    A group of poly (phthalazinone ether sulfone ketone)/potassium-titanate-whisker (PPSEK/whisker) composites was prepared by coprecipitation from solution. The whisker surface was modified using titanate coupling agent prior to blending. The tensile, impact, morphology and thermal properties of the moulded composites were investigated.The measurements showed that the tensile strength and impact strength of the composites increased with increasing whiskers content up to 10 to 20 phr, thereafter they showed a decrease in the whiskers content reached 40 phr.At the same time, the modulus of the composites increased with increasing whiskers content. Scanning electron microscopy studies revealed that the whiskers within the composites were dispersed uniformly by treated with coupling agent. Finally, thermogravimetric analysis showed that the heat resistance of the composites tended to increase with increasing whisker content. The results were analysed and discussed in terms of established models of the behaviour of short-fiber reinforced composites.

  7. Shear behavior of reinforced Engineered Cementitious Composites (ECC) beams

    Paegle, Ieva; Fischer, Gregor


    This paper describes an experimental investigation of the shear behavior of beams consisting of steel reinforced Engineered Cementitious Composites (ECC). Based on the strain hardening and multiple cracking behavior of ECC, this study investigates the extent to which ECC can improve the shear...... randomly distributed PVA (polyvinyl alcohol) fiber beams with different stirrup spacing and reinforced concrete (RC) beams for comparison. Displacement and strain measurements taken using the ARAMIS photogrammetric data acquisition system by means of processing at high frame rate captured images of applied...

  8. Wear Behaviour of Carbon Nanotubes Reinforced Nanocrystalline AA 4032 Composites

    Senthil Saravanari, M. S.; Kumaresh Babu, S. P.; Sivaprasad, K.


    The present paper emphasizes the friction and wear properties of Carbon Nanotubes reinforced AA 4032 nanocomposites prepared by powder metallurgy technique. CNTs are multi-wall in nature and prepared by electric arc discharge method. Multi-walled CNTs are blended with AA 4032 elemental powders and compaction followed by sintering to get bulk nanocomposites. The strength of the composites has been evaluated by microhardness and the surface contact between the nanocomposites and EN 32 steel has been evaluated by Pin on disk tester. The results are proven that reinforcement of CNTs play a major role in the enhancement of hardness and wear.

  9. Fabrication and mechanical properties of self-reinforced poly(ethylene terephthalate composites


    Full Text Available Self-reinforced poly(ethylene terephthalate (PET composites prepared by using a modified film-stacking technique were examined in this study. The starting materials included a high tenacity PET yarn (reinforcement and a low melting temperature biodegradable polyester resin (matrix, both of which differ in their melting temperatures with a value of 56°C. This experiment produced composite sheets at three consolidation temperatures (Tc: 215, 225, and 235°C at a constant holding time (th: 6.5 min, and three holding times (3, 6.5 and 10 min at a constant consolidation temperature of 225°C. This study observed a significant improvement in the mechanical properties obtained in self-reinforced PET composites compared to the pure polyester resin. The results of tensile, flexural, and Izod impact tests proved that optimal conditions are low consolidation temperature and short holding time. The absorbed impact energy of the best self-reinforced PET composite material was 854.0 J/m, which is 63 times that of pure polyester resin.

  10. Durability of Cement Composites Reinforced with Sisal Fiber

    Wei, Jianqiang

    understanding of degradation mechanisms, two approaches are proposed to mitigate the degradation of sisal fiber in the cement matrix. In order to relieve the aggressive environment of hydrated cement, cement substitution by a combination of metakaolin and nanoclay, and a combination of rice husk ash and limestone are studied. Both metakaolin and nanoclay significantly optimize the cement hydration, while the combination of these two supplementary cementitious materials validates their complementary and synergistic effect at different stages of aging. The presented approaches effectively reduce the calcium hydroxide content and the alkalinity of the pore solution, thereby mitigating the fiber degradation and improving both the initial mechanical properties and durability of the fiber-cement composites. The role of rice husk ash in cement modification is mainly as the active cementitious supplementary material. In order to improve the degradation resistance of sisal fiber itself, two novel, simple, and economical pretreatments of the fibers (thermal and sodium carbonate treatment) are investigated. Both thermal treatment and Na 2CO3 treatment effectively improve the durability of sisal fiber-reinforced concrete. The thermal treatment achieves improvement of cellulose's crystallization, which ensures the initial strength and improved durability of sisal fiber. A layer consisting of calcium carbonate sediments, which protects the internals of a fiber from the strong alkali pore solution, is formed and filled in pits and cavities on the Na2CO3 treated sisal fiber's surface.

  11. Examining of abrasion resistance of hybrid composites reinforced with SiC and Cgr particles

    M. Łągiewka


    Full Text Available The presented work discusses the influence of the type and volume percentage of particulate reinforcement consisting of mixed silicon carbide and graphite on the abrasion wear of hybrid composites with AlMg10 matrix. Also the macro photos of frictional surfaces have been shown and the results of hardness measurements have been presented. The performed examinations have allowed for stating that the mixture of SiC and Cgr particles changes in favour the tribological properties of the matrix alloy. It has been also proved that introducing hard reinforcing particles along with soft lubricating ones allows for achieving the material exhibiting high abrasion resistance, and moreover, the graphite particles protect the abraded surface from the destructive action of silicon carbide particles. Also hardness measurements have been performed and the resulting conclusion is that the composite hardness increases with an increase in volume fraction of the reinforcing particles.

  12. Effect of sintering temperatures on titanium matrix composites reinforced by ceramic particles

    Romero, F.; Amigo, V.; Busquets, D.; Klyatskina, E. [Mechanical and Materials Engineering Department. Polytechnical University of Valencia, Valencia (Spain)


    Titanium and titanium composites have a potential use in aerospace and biotechnology industries, and nowadays in others like sports and fashion ones. In this work composite materials, based on titanium matrix reinforced with ceramic particles, have been developed. PM route is used to obtain compact and sintered samples. TiN and TiAl powders, are milled with Ti powder in different volumetric percentages in a ball mill. These mixtures are pressed in a uniaxial press and sintered in a vacuum furnace at different temperatures between 1180 to 1220 deg. C. Porosity of samples is analysed, before and after the sintering process, by Archimedes technique and by image analysis. Mechanical properties and the reinforcement particles influence in the titanium matrix are studied by flexion test in green and sintered states, and by hardness and microhardness tests. Complimentarily, a microstructural analysis is carried out by optical and electron microscopy, and the reactivity between the reinforce particles and titanium matrix are studied. (authors)

  13. Preparation technique of SiCp reinforced Al matrix composite

    HAO Bin; CUI Hua; YU Zhi-yong; TAO Kai; YANG Bin; ZHANG Ji-shan


    A new preparation technique-"block dispersal and cast" method is introduced, and three kinds of mixing methods, vertical, horizontal and inclining styles, are compared. The results demonstrate that the inclining style is the best way to mix powders. The Al and nano SiC powders are pressed into blocks, dipped into molten Al, stirred into mold so that SiC/Al matrix composites can be obtained at last. The microstructure of SiC particle reinforced Al matrix composite prepared by "block dispersal and cast" method have been studied using scanning electron microscopy (SEM). Phase analysis has also been conducted by means of X-ray diffraction (XRD). The results show that nano SiC particles can be dispersed uniformly in Al matrix. Thus, it is feasible to prepare SiC particle reinforced Al matrix composites by this method.

  14. Mechanical Behavior of Hybrid Glass/Steel Fiber Reinforced Epoxy Composites

    Amanda K. McBride


    Full Text Available While conventional fiber-reinforced polymer composites offer high strength and stiffness, they lack ductility and the ability to absorb energy before failure. This work investigates hybrid fiber composites for structural applications comprised of polymer, steel fiber, and glass fibers to address this shortcoming. Varying volume fractions of thin, ductile steel fibers were introduced into glass fiber reinforced epoxy composites. Non-hybrid and hybrid composite specimens were prepared and subjected to monolithic and half-cyclic tensile testing to obtain stress-strain relationships, hysteresis behavior, and insight into failure mechanisms. Open-hole testing was used to assess the vulnerability of the composites to stress concentration. Incorporating steel fibers into glass/epoxy composites offered a significant improvement in energy absorption prior to failure and material re-centering capabilities. It was found that a lower percentage of steel fibers (8.2% in the hybrid composite outperformed those with higher percentages (15.7% and 22.8% in terms of energy absorption and re-centering, as the glass reinforcement distributed the plasticity over a larger area. A bilinear hysteresis model was developed to predict cyclic behavior of the hybrid composite.

  15. Development of Cu Reinforced SiC Particulate Composites

    Singh, Harshpreet; Kumar, Lailesh; Nasimul Alam, Syed


    This paper presents the results of Cu-SiCp composites developed by powder metallurgy route and an attempt has been made to make a comparison between the composites developed by using unmilled Cu powder and milled Cu powder. SiC particles as reinforcement was blended with unmilled and as-milled Cu powderwith reinforcement contents of 10, 20, 30, 40 vol. % by powder metallurgy route. The mechanical properties of pure Cu and the composites developed were studied after sintering at 900°C for 1 h. Density of the sintered composites were found out based on the Archimedes' principle. X-ray diffraction of all the composites was done in order to determine the various phases in the composites. Scanning electron microscopy (SEM) and EDS (electron diffraction x-ray spectroscopy) was carried out for the microstructural analysis of the composites. Vickers microhardness tester was used to find out the hardness of the samples. Wear properties of the developed composites were also studied.

  16. Glass fibres reinforced polyester composites degradation monitoring by surface analysis

    Croitoru, Catalin [“Transilvania” University of Brasov, Materials Engineering and Welding Department, Eroilor 29 Str., 500036 Brasov (Romania); Patachia, Silvia, E-mail: [“Transilvania” University of Brasov, Product Design Environment and Mechatronics Department, Eroilor 29 Str., 500036 Brasov (Romania); Papancea, Adina [“Transilvania” University of Brasov, Product Design Environment and Mechatronics Department, Eroilor 29 Str., 500036 Brasov (Romania); Baltes, Liana; Tierean, Mircea [“Transilvania” University of Brasov, Materials Engineering and Welding Department, Eroilor 29 Str., 500036 Brasov (Romania)


    Highlights: • Glass fibre-reinforced polyester composites surface analysis by photographic method. • The composites are submitted to accelerated ageing by UV irradiation at 254 nm. • The UV irradiation promotes differences in the surface chemistry of the composites. • MB dye is differently adsorbed on surfaces with different degradation degrees. • Good correlation between the colouring degree and surface chemistry. - Abstract: The paper presents a novel method for quantification of the modifications that occur on the surface of different types of gel-coated glass fibre-reinforced polyester composites under artificial UV-ageing at 254 nm. The method implies the adsorption of an ionic dye, namely methylene blue, on the UV-aged composite, and computing the CIELab colour space parameters from the photographic image of the coloured composite's surface. The method significantly enhances the colour differences between the irradiated composites and the reference, in contrast with the non-coloured ones. The colour modifications that occur represent a good indicative of the surface degradation, alteration of surface hydrophily and roughness of the composite and are in good correlation with the ATR-FTIR spectroscopy and optical microscopy results. The proposed method is easier, faster and cheaper than the traditional ones.

  17. Experimental Investigation into Shaping Particle-reinforced Material by WEDM-H

    T; M; Yue


    Al 2O 3 particle-reinforced material (6061 alloy ), which is one of new composites and characterized by high strength and small spe cific gravity, good wear resistance and corrosion resistance, has been widel y used in industry. But it is difficult to machine. Because of electric conducti vity, it can be shaped and processed by electro-machining means. However, this kind of material is mixed with the electrically conductive substances and the di electrically conductive substances, its machining proces...

  18. Self-healing in single and multiple fiber(s reinforced polymer composites

    Woldesenbet E.


    Full Text Available You Polymer composites have been attractive medium to introduce the autonomic healing concept into modern day engineering materials. To date, there has been significant research in self-healing polymeric materials including several studies specifically in fiber reinforced polymers. Even though several methods have been suggested in autonomic healing materials, the concept of repair by bleeding of enclosed functional agents has garnered wide attention by the scientific community. A self-healing fiber reinforced polymer composite has been developed. Tensile tests are carried out on specimens that are fabricated by using the following components: hollow and solid glass fibers, healing agent, catalysts, multi-walled carbon nanotubes, and a polymer resin matrix. The test results have demonstrated that single fiber polymer composites and multiple fiber reinforced polymer matrix composites with healing agents and catalysts have provided 90.7% and 76.55% restoration of the original tensile strength, respectively. Incorporation of functionalized multi-walled carbon nanotubes in the healing medium of the single fiber polymer composite has provided additional efficiency. Healing is found to be localized, allowing multiple healing in the presence of several cracks.

  19. Self-healing in single and multiple fiber(s) reinforced polymer composites

    Woldesenbet, E.


    You Polymer composites have been attractive medium to introduce the autonomic healing concept into modern day engineering materials. To date, there has been significant research in self-healing polymeric materials including several studies specifically in fiber reinforced polymers. Even though several methods have been suggested in autonomic healing materials, the concept of repair by bleeding of enclosed functional agents has garnered wide attention by the scientific community. A self-healing fiber reinforced polymer composite has been developed. Tensile tests are carried out on specimens that are fabricated by using the following components: hollow and solid glass fibers, healing agent, catalysts, multi-walled carbon nanotubes, and a polymer resin matrix. The test results have demonstrated that single fiber polymer composites and multiple fiber reinforced polymer matrix composites with healing agents and catalysts have provided 90.7% and 76.55% restoration of the original tensile strength, respectively. Incorporation of functionalized multi-walled carbon nanotubes in the healing medium of the single fiber polymer composite has provided additional efficiency. Healing is found to be localized, allowing multiple healing in the presence of several cracks.

  20. Strong and light-weight materials made of reinforced honeycomb sandwich structures

    Mikkelsen, Lars Pilgaard; Madsen, Bo

    a low cost, in order for them to compete with conventionally used materials like steel or aluminum. A great candidate for a material that can fulfil these requirements of being light, strong and low cost is a sandwich material. A sandwich material is a material that is made of a light-weight core...... with a thin layer of steel or fibre composite on top and bottom of the core. The core in a sandwich material is typically made of a honeycomb structure. Honeycomb structures have been used for more than 50 years. Until now honeycombs have been expensive to produce. However, with a new production method...... it is now possible to produce honeycombs structures at a low cost. In a large collaborative European project called INCOM, the possibility of reinforcing the honeycomb structure is investigated. The honeycomb structure is reinforced with sustainable fibres as the fibres are extracted from saw dust....

  1. DOE Automotive Composite Materials Research: Present and Future Efforts

    Warren, C.D.


    One method of increasing automotive energy efficiency is through mass reduction of structural components by the incorporation of composite materials. Significant use of glass reinforced polymers as structural components could yield a 20--30% reduction in vehicle weight while the use of carbon fiber reinforced materials could yield a 40--60% reduction in mass. Specific areas of research for lightweighting automotive components are listed, along with research needs for each of these categories: (1) low mass metals; (2) polymer composites; and (3) ceramic materials.

  2. Epoxy-based carbon nanotubes reinforced composites

    Kesavan Pillai, Sreejarani


    Full Text Available ). After curing the composite film system, the substrate was etched from the backside by deep reactive ion etching (DRIE) which left a circular thin film on the rigid substrate with a hole 8 mm in diameter. Extensive examination of the CNT... treatment or plasma oxidation to improve interfacial bonding and dispersion of nanotubes in the epoxy matrix. CVD-grown MWCNTs with average diameter of 13 nm and length of 10 ?m, epoxy resin (YD 128) and hardener (TH 432) were used in the study. The CNTs...

  3. Chemical modification of flax reinforced polypropylene composites

    Jacob John, Maya


    Full Text Available ) and ∆Ea is the activation energy for the relaxation. The slope of Arrhenius plot obtained by plotting log f versus 1/T will give the activation energy for that process. Table 3 presents the activation energy of the composites and it can be observed... at the temperature where the loss modulus is maximum indicating a relaxation phenomenon. The increase in loss modulus is attributed to the increase in energy absorption caused by the addition of fibres. Mechanical damping factor (tan δ) Page 9 of 26...

  4. Effect of reinforcement type and porosity on strength of metal matrix composite

    Kulkarni, S. G.; Lal, Achchhe; Menghani, J. V.


    In the present work, experimental investigation and the numerical analysis are carried out for strength analysis of A356 alloy matrix composites reinforced with alumina, fly ash and hybrid particle composites. The combined strengthening effect of load bearing, Hall-Petch, Orowan, coefficient of thermal expansion mismatch and elastic modulus mismatch is studied for predicting accurate uniaxial stress-strain behavior of A356 based alloy matrix composite. The unit cell micromechanical approach and nine noded isoparametric finite element analysis (FEA) is used to investigate the yield failure load by considering material defect of porosity as fabrication errors in particulate composite. The Ramberg-Osgood approach is considered for the linear and nonlinear relationship between stress and strain of A356 based metal matrix composites containing different amounts of fly ash and alumina reinforcing particles. A numerical analysis of material porosity on the stress strain behavior of the composite is performed. The literature and experimental results exhibit the validity of this model and confirm the importance of the fly ash as the cheapest and low density reinforcement obtained as a waste by product in thermal power plants.

  5. Improving Impact Strength Recovery of Fractured and Healed Rice Husks Fibre Reinforced Polypropylene Composites.

    Odhong, O.V.E


    Full Text Available Rice husks fibre reinforced polypropylene composite (rhfrpc is a natural plant fibre reinforced polymer composite having advantages of high strength, light weight and affordability. They are commonly used for light load structural and non structural applications. They are mainly used as particle boards, for fencing post, roofing tiles, for interiors of car and aircrafts among other usages. This material once cracked by impact forces cannot be repaired using traditional repair methods for engineering materials such as metals or other composites that can be repaired by welding or by patch repair methods respectively, thus a method of repair of rice husks fibre reinforced polypropylene composites by refilling the damaged volume by injection of various healing agents has been investigated. The composite coupons were produced by injection moulding, cooled sufficiently and prepared for charpy impact tests. Test results for pristine coupons were a maximum of 48 J/mm2 . The destroyed coupons were then subjected to healing in a fabricated healing fixture. Healing agents such as epoxy resin, ethyl cyanoacrylate, and tannin gum have been investigated for their use as possible healing agents to fill the damaged volume and perform healing action at the fractured surfaces. The impact test results were recorded and compared with those of unhealed pristine coupons. The recovered strengths were a maximum of 60 J/mm2 translating into a 125% impact strength recovery, and this is good enough for the healed composites to be recommended for reuse in their second lives of their respective original functions.

  6. Carbon-Nanotube-Reinforced Polymer-Derived Ceramic Composites

    An, Linan; Xu, Weixing; Rajagopalan, Sudhir; Wang, Chong M.; Wang, Hsin; Fan, Yi; Zhang, Ligong; Jiang, Dapeng; Kapat, Jay; Chow, Louis; Guo, Baohua; Liang, Ji; Vaidyanathan, Raj


    Carbon nanotube reinforced ceramic composites were synthesized by using recently developed polymer-derived ceramics as matrices. Multi-wall carbon nanotubes, treated with a surfactant, were first dispersed in a liquid polymer precursor by sonication and mechanical stirring. The solution was then converted to fully dense ceramic composites with pressure-assist pyrolysis technique. Microstructural observation revealed that nanotubes were homogeneously dispersed throughout the ceramic matrix. Significant increases in mechanical and thermal properties were observed by adding only {approx}6vol% nanotubes. Strong nanotube pullout revealed by SEM observation suggested that the composites could possess high fracture toughness.

  7. Micromechanical Modeling of Fiber-Reinforced Composites with Statistically Equivalent Random Fiber Distribution

    Wenzhi Wang


    Full Text Available Modeling the random fiber distribution of a fiber-reinforced composite is of great importance for studying the progressive failure behavior of the material on the micro scale. In this paper, we develop a new algorithm for generating random representative volume elements (RVEs with statistical equivalent fiber distribution against the actual material microstructure. The realistic statistical data is utilized as inputs of the new method, which is archived through implementation of the probability equations. Extensive statistical analysis is conducted to examine the capability of the proposed method and to compare it with existing methods. It is found that the proposed method presents a good match with experimental results in all aspects including the nearest neighbor distance, nearest neighbor orientation, Ripley’s K function, and the radial distribution function. Finite element analysis is presented to predict the effective elastic properties of a carbon/epoxy composite, to validate the generated random representative volume elements, and to provide insights of the effect of fiber distribution on the elastic properties. The present algorithm is shown to be highly accurate and can be used to generate statistically equivalent RVEs for not only fiber-reinforced composites but also other materials such as foam materials and particle-reinforced composites.

  8. Laser processed TiN reinforced Ti6Al4V composite coatings.

    Balla, Vamsi Krishna; Bhat, Abhimanyu; Bose, Susmita; Bandyopadhyay, Amit


    The purpose of this first generation investigation is to evaluate fabrication, in vitro cytotoxicity, cell-material interactions and tribological performance of TiN particle reinforced Ti6Al4V composite coatings for potential wear resistant load bearing implant applications. The microstructural analysis of the composites was performed using scanning electron microscope and phase analysis was done with X-ray diffraction. In vitro cell-material interactions, using human fetal osteoblast cell line, have been assessed on these composite coatings and compared with Ti6Al4V alloy control samples. The tribological performance of the coatings were evaluated, in simulated body fluids, up to 1000 m sliding distance under 10 N normal load. The results show that the composite coatings contain distinct TiN particles embedded in α+β phase matrix. The average top surface hardness of Ti6Al4V alloy increased from 394±8 HV to 1138±61 HV with 40 wt% TiN reinforcement. Among the composite coatings, the coatings reinforced with 40 wt% TiN exhibited the highest wear resistance of 3.74×10(-6) mm(3)/Nm, which is lower than the wear rate, 1.04×10(-5) mm(3)/Nm, of laser processed CoCrMo alloy tested under identical experimental conditions. In vitro biocompatibility study showed that these composite coatings were non-toxic and provides superior cell-material interactions compared to Ti6Al4V control, as a result of their high surface energy. In summary, excellent in vitro wear resistance and biocompatibility of present laser processed TiN reinforced Ti6Al4V alloy composite coatings clearly show their potential as wear resistant contact surfaces for load bearing implant applications.

  9. 78 FR 16044 - Hazardous Materials Packaging-Composite Cylinder Standards; Public Meeting


    ... reinforced plastic (DOT-FRP) or fully wrapped carbon-fiber reinforced aluminum lined cylinders (DOT- CFFC... TRANSPORTATION Pipeline and Hazardous Materials Safety Administration Hazardous Materials Packaging--Composite... the manufacture, marking, sale and use of non-DOT specification composite cylinders. The...

  10. Microstructure of a cement matrix composite reinforced with polypropylene fibers

    Rincón, J. M.


    Full Text Available The present investigation deals with the microstructural characterization of a composite material, which is comprised of polypropylene fibers in an cement matrix, by means of environmental scanning electron microscopy (ESEM and field emission scanning electron microscopy (FESEM. The microstructure of the different phases that compose the matrix is very heterogeneous, though there is a uniform distribution of the fibers inside it. The surface of this composite is different after setting, cured and hardening depending if the zone is or not in touch with the walls of the mould. The interface between the different crystalline regions of the cement matrix and the dispersed fibers shows compatibility between the matrix and the polymeric fibers. The mechanical properties (compression and bending strength have also been evaluated. The use of melamine formaldehyde as additive leads to a reinforcement of the cement matrix and to the improvement of the mechanical properties.

    Se ha llevado a cabo una observacíón microestructural detallada de un material compuesto de fibras de polipropileno embebidas en una matriz de cemento usando los nuevos tipos de microscopía electrónica de barrido, tales como: un microscopio electrónico medioambiental (acrónimo en inglés: ESEM y uno de emisión de campo (acrónimo en inglés: FESEM. La microestructura de las diferentes fases que componen la matriz es muy heterogénea, aunque hay una distribución uniforme de las fibras dentro de ellas. La superficie de este material compuesto es diferente después del fraguado, curado y endurecimiento según qué zonas estén o no en contacto con las paredes del molde. La interfase entre las diferentes fases cristalinas de la matriz de cemento y las fibras dispersadas se ha observado a diferentes aumentos, comprobándose compatibilidad entre la matriz y las fibras poliméricas. Las propiedades de resistencia mecánica (tanto a flexión como a compresión han sido tambi

  11. Damage tolerance of continuous fibre composites: material and environmental effects

    Bibo, G.A.; Hogg, P.J. [Queen Mary and Westfield Coll., London (United Kingdom). Dept. of Materials


    Aerospace design philosophies are used to discuss critically, the suitability of composite materials to primary structural applications. The principal issues limiting the use of composites, compression after impact performance and high cost, are examined in terms of material/manufacturing form and environmental conditioning. The material types investigated consist of thermoset and thermoplastic matrix reinforced unidirectional prepreg tape and textile manufactured architectures. (orig.) 141 refs.

  12. Banana fiber-reinforced biodegradable soy protein composites

    Rakesh Kumar; Veena Choudhary; Saroj Mishra; Ik Varma


    Banana fiber,a waste product of banana cultivation,has been used to prepare banana fiber reinforced soy protein composites. Alkali modified banana fibers were characterized in terms of density,denier and crystallinity index. Fourier transformed infrared spectroscopy (FTIR),scanning electron microscopy (SEM) and thermogravimetric analysis (TGA) were also performed on the fibers. Soy protein composites were prepared by incorporating different volume fractions of alkali,treated and untreated fibers into soy protein isolate (SPI) with different amounts of glycerol (25%,50%) as plasticizer.Composites thus prepared were characterized in terms of mechanical properties,SEM and water resistance.The results indicate that at 0.3 volume fraction,tensile strength and modulus of alkali treated fiber reinforced soy protein composites increased to 82% and 963%,respectively,compared to soy protein film without fibers.Water resistance of the composites increased significantly with the addition of glutaraldehyde which acts as crosslinking agent. Biodegradability of the composites has also been tested in the contaminated environment and the composites were found to be 100% biodegradable.

  13. Investigation of Coating Capability of Composite Materials

    Yelda Akçin


    Full Text Available Nowadays, composite materials are widely used in the sectors that are overrated high strength / density and high elasticity modulus / density ratios such as defense industry, marine transportation, automotive and aerospace industry. However, because of the surface properties such as tribological behavior and low wear resistance their application areas are limited. Coating is the prominent process in order to improve these properties of the materials. In this study, hard ceramic powders (Al2O3 + TiO2 and CrO3 are coated to surface of glass fiber and carbon fiber reinforced epoxy matrix composite materials with plasma spray coating method started to be widely used todays and physical, mechanical and metallographic properties of obtained coatings were examined.

  14. Water Absorption Behaviour and Its Effect on the Mechanical Properties of Flax Fibre Reinforced Bioepoxy Composites

    E. Muñoz


    Full Text Available In the context of sustainable development, considerable interest is being shown in the use of natural fibres like as reinforcement in polymer composites and in the development of resins from renewable resources. This paper focuses on eco-friendly and sustainable green composites manufacturing using resin transfer moulding (RTM process. Flax fibre reinforced bioepoxy composites at different weight fractions (40 and 55 wt% were prepared in order to study the effect of water absorption on their mechanical properties. Water absorption test was carried out by immersion specimens in water bath at room temperature for a time duration. The process of water absorption of these composites was found to approach Fickian diffusion behavior. Diffusion coefficients and maximum water uptake values were evaluated; the results showed that both increased with an increase in fibre content. Tensile and flexural properties of water immersed specimens were evaluated and compared to dry composite specimens. The results suggest that swelling of flax fibres due to water absorption can have positive effects on mechanical properties of the composite material. The results of this study showed that RTM process could be used to manufacture natural fibre reinforced composites with good mechanical properties even for potential applications in a humid environment.

  15. Transverse isotropic modeling of the ballistic response of glass reinforced plastic composites

    Taylor, P.A. [Sandia National Labs., Albuquerque, NM (United States)


    The use of glass reinforced plastic (GRP) composites is gaining significant attention in the DoD community for use in armor applications. These materials typically possess a laminate structure consisting of up to 100 plies, each of which is constructed of a glass woven roving fabric that reinforces a plastic matrix material. Current DoD attention is focused on a high strength, S-2 glass cross-weave (0/90) fabric reinforcing a polyester matrix material that forms each ply of laminate structure consisting anywhere from 20 to 70 plies. The resulting structure displays a material anisotropy that is, to a reasonable approximation, transversely isotropic. When subjected to impact and penetration from a metal fragment projectile, the GRP displays damage and failure in an anisotropic manner due to various mechanisms such as matrix cracking, fiber fracture and pull-out, and fiber-matrix debonding. In this presentation, the author will describe the modeling effort to simulate the ballistic response of the GRP material described above using the transversely isotropic (TI) constitutive model which has been implemented in the shock physics code, CTH. The results of this effort suggest that the model is able to describe the delamination behavior of the material but has some difficulty capturing the in-plane (i.e., transverse) response of the laminate due to its cross-weave fabric reinforcement pattern which causes a departure from transverse isotropy.


    周莉; 张建中; 张林


    This paper use MEKP as curing agent, use cobalt iso-octoate as promote agent, study various different ratio of composition on mechanical properties influence. A short cut glass fibre felt reinforced unsaturated polyester resin composite material take the unsaturated polyester as a substrate, take the glass fiber as reinforced material, adding the promoting agent, firming agent and other additives, through the normal temperature solidification obtains its plate.%以不饱和聚醋为基体,玻璃纤维毡为增强材料,用过氧化甲乙酮为固化剂、异辛酸钴为促进剂,常温固化得到复合材料.研究固化剂、促进剂不同加入量和配比对材料力学性能的影响.

  17. Mechanical and Wear Properties of SiC/Graphite Reinforced Al359 Alloy-based Metal Matrix Composite

    Shubhranshu Bansal


    Full Text Available Al359 alloy was reinforced with Silicon Carbide and Silicon Carbide/Graphite particles using stir casting process. Thereafter their mechanical and wear properties were investigated. It was found that the hardness of the Al359-Silicon Carbide composite is better than Al359-Silicon Carbide-Graphite composite. The Silicon Carbide/Graphite reinforced composite exhibits a superior ultimate tensile strength against Silicon Carbide reinforced composite. The wear test was conducted at different loading, sliding velocities and sliding distances conditions. Results showed that the wear resistance of Al359 alloy increased with the reinforcement of Silicon Carbide/Graphite material for higher loading, sliding velocities and sliding distance conditions. SEM images of the worn surface of the pin were examined to study their wear mechanism.Defence Science Journal, Vol. 65, No. 4, July 2015, pp. 330-338, DOI:

  18. Development of hierarchical cellulosic reinforcement for polymer composites


    Cellulose is an environmentally friendly material which is obtainable in vast quantities, since it is present in every plant. Cellulosic fibers are commercially found in two forms: natural (flax, hemp, cotton, sisal, wood, etc.) and regenerated cellulose fibers (RCF). The biodegradability, the morphological and mechanical properties make these fibers a good alternative to the synthetic reinforcement (e.g. glass fibers). However, as all other cellulosic fibers these materials also have similar...

  19. Impact behavior of a SiC fiber-reinforced reaction bonded Si3N4 composite

    Grady, J.; Bhatt, R.; Klima, S.


    Impact tests were performed on a series of ceramic plate specimens. Monolithic (unreinforced) and composite specimens with various fiber layups were tested to determine the effect that the fiber reinforcement has on impact damage initiation and dynamic response of the ceramic materials. Results show that a porous surface layer of Si3N4 on the composite specimens can enhance the energy absorbing capability of the composite specimens. The addition of SiC fiber reinforcement to the RBSN matrix material is also shown to significantly change the mode of failure and reduce the extent of damage due to impact.

  20. Finite element modelling of fibre-reinforced brittle materials

    Kullaa, J.


    The tensile constitutive behaviour of fibre-reinforced brittle materials can be extended to two or three dimensions by using the finite element method with crack models. The three approaches in this study include the smeared and discrete crack concepts and a multi-surface plasticity model. The tensi

  1. Mechanical Performance of Rotomoulded Wollastonite-Reinforced Polyethylene Composites

    Yuan, Xiaowen; Easteal, Allan J.; Bhattacharyya, Debes

    This paper describes the development of a new processing technology for rotational moulding of wollastonite microfibre (WE) reinforced polyethylene (PE). Manufacturing wollastonite-polyethylene composites involved blending, compounding by extrusion, and granulating prior to rotational moulding. The properties of the resulting composites were characterised by tensile and impact strength measurements. The results show that tensile strength increases monotonically with the addition of wollastonite fibres, but impact strength is decreased. In addition, the processability is also decreased after adding more than 12 vol% WE because of increased viscosity. The effects of a coupling agent, maleated polyethylene (MAPE), on the mechanical performance and processability were also investigated. SEM analysis reveals good adhesion between the fibre reinforcements and polyethylene matrix at the fracture surface with the addition of MAPE. It is proposed that fillers with small particles with high aspect ratio (such as wollastonite) provide a large interfacial area between the filler and the polymer matrix, and may influence the mobility of the molecular chains.

  2. Discontinuously reinforced intermetallic matrix composites via XD synthesis. [exothermal dispersion

    Kumar, K. S.; Whittenberger, J. D.


    A review is given of recent results obtained for discontinuously reinforced intermetallic matrix composites produced using the XD process. Intermetallic matrices investigated include NiAl, multiphase NiAl + Ni2AlTi, CoAl, near-gamma titanium aluminides, and Ll2 trialuminides containing minor amounts of second phase. Such mechanical properties as low and high temperature strength, compressive and tensile creep, elastic modulus, ambient ductility, and fracture toughness are discussed as functions of reinforcement size, shape, and volume fraction. Microstructures before and after deformation are examined and correlated with measured properties. An observation of interest in many of the systems examined is 'dispersion weakening' at high temperatures and high strain rates. This behavior is not specific to the XD process; rather similar observations have been reported in other discontinuous composites. Proposed mechanisms for this behavior are presented.

  3. Fabrication Of Carbon-Boron Reinforced Dry Polymer Matrix Composite Tape

    Belvin, Harry L.; Cano, Roberto J.; Treasure, Monte; Shahood, Thomas W.


    Future generation aerospace vehicles will require specialized hybrid material forms for component structure fabrication. For this reason, high temperature composite prepregs in both dry and wet forms are being developed at NASA Langley Research Center (LaRC). In an attempt to improve compressive properties of carbon fiber reinforced composites, a hybrid carbon-boron tape was developed and used to fabricate composite laminates which were subsequently cut into flexural and compression specimens and tested. The hybrid material, given the designation HYCARB, was fabricated by modifying a previously developed process for the manufacture of dry polymer matrix composite (PMC) tape at LaRC. In this work, boron fibers were processed with IM7/LaRC(TradeMark)IAX poly(amide acid) solution-coated prepreg to form a dry hybrid tape for Automated Tow Placement (ATP). Boron fibers were encapsulated between two (2) layers of reduced volatile, low fiber areal weight poly(amide acid) solution-coated prepreg. The hybrid prepreg was then fully imidized and consolidated into a dry tape suitable for ATP. The fabrication of a hybrid boron material form for tow placement aids in the reduction of the overall manufacturing cost of boron reinforced composites, while realizing the improved compression strengths. Composite specimens were press-molded from the hybrid material and exhibited excellent mechanical properties.


    Joan P. López,


    Full Text Available The behavior of stone groundwood / polypropylene injection-molded composites was evaluated with and without coupling agent. Stone groundwood (SGW is a fibrous material commonly prepared in a high yield process and mainly used for papermaking applications. In this work, the use of SGW fibers was explored as a reinforcing element of polypropylene (PP composites. The surface charge density of the composite components was evaluated, as well as the fiber’s length and diameter inside the composite material. Two mixing extrusion processes were evaluated, and the use of a kinetic mixer, instead of an internal mixer, resulted in longer mean fiber lengths of the reinforcing fibers. On the other hand, the accessibility of surface hydroxyl groups of stone groundwood fibers was improved by treating the fibers with 5% of sodium hydroxide, resulting in a noticeable increase of the tensile strength of the composites, for a similar percentage of coupling agent. A new parameter called Fiber Tensile Strength Factor is defined and used as a baseline for the comparison of the properties of the different composite materials. Finally the competitiveness of stone groundwood / polypropylene / polypropylene-co-maleic anhydride system, which compared favorably to sized glass-fiber / polypropylene GF/PP and glass-fiber / polypropylene / polypropylene-co-maleic anhydride composite formulations, was quantified by means of the fiber tensile strength factor.

  5. Additive Manufacturing and Characterization of Polylactic Acid (PLA) Composites Containing Metal Reinforcements

    Kuentz, Lily; Salem, Anton; Singh, M.; Halbig, M. C.; Salem, J. A.


    Additive manufacturing of polymeric systems using 3D printing has become quite popular recently due to rapid growth and availability of low cost and open source 3D printers. Two widely used 3D printing filaments are based on polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS) systems. PLA is much more environmentally friendly in comparison to ABS since it is made from renewable resources such as corn, sugarcane, and other starches as precursors. Recently, polylactic acid-based metal powder containing composite filaments have emerged which could be utilized for multifunctional applications. The composite filaments have higher density than pure PLA, and the majority of the materials volume is made up of polylactic acid. In order to utilize functionalities of composite filaments, printing behavior and properties of 3-D printed composites need to be characterized and compared with the pure PLA materials. In this study, pure PLA and composite specimens with different metallic reinforcements (Copper, Bronze, Tungsten, Iron, etc) were 3D printed at various layer heights and resulting microstructures and properties were characterized. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) behavior of filaments with different reinforcements were studied. The microscopy results show an increase in porosity between 3-D printed regular PLA and the metal composite PLA samples, which could produce weaker mechanical properties in the metal composite materials. Tensile strength and fracture toughness behavior of specimens as a function of print layer height will be presented.

  6. Glass fibres reinforced polyester composites degradation monitoring by surface analysis

    Croitoru, Catalin; Patachia, Silvia; Papancea, Adina; Baltes, Liana; Tierean, Mircea


    The paper presents a novel method for quantification of the modifications that occur on the surface of different types of gel-coated glass fibre-reinforced polyester composites under artificial UV-ageing at 254 nm. The method implies the adsorption of an ionic dye, namely methylene blue, on the UV-aged composite, and computing the CIELab colour space parameters from the photographic image of the coloured composite's surface. The method significantly enhances the colour differences between the irradiated composites and the reference, in contrast with the non-coloured ones. The colour modifications that occur represent a good indicative of the surface degradation, alteration of surface hydrophily and roughness of the composite and are in good correlation with the ATR-FTIR spectroscopy and optical microscopy results. The proposed method is easier, faster and cheaper than the traditional ones.

  7. Optimization and Static Stress Analysis of Hybrid Fiber Reinforced Composite Leaf Spring

    Luay Muhammed Ali Ismaeel


    Full Text Available A monofiber reinforced composite leaf spring is proposed as an alternative to the typical steel one as it is characterized by high strength-to-weight ratio. Different reinforcing schemes are suggested to fabricate the leaf spring. The composite and the typical steel leaf springs are subjected to the same working conditions. A weight saving of about more than 60% can be achieved while maintaining the strength for the structures under consideration. The objective of the present study was to replace material for leaf spring. This study suggests various materials of hybrid fiber reinforced plastics (HFRP. Also the effects of shear moduli of the fibers, matrices, and the composites on the composites performance and responses are discussed. The results and behaviors of each are compared with each other and verified by comparison with analytical solution; a good convergence is found between them. The elastic properties of the hybrid composites are calculated using rules of mixtures and Halpin-Tsi equation through the software of MATLAB v-7. The problem is also analyzed by the technique of finite element analysis (FEA through the software of ANSYS v-14. An element modeling was done for every leaf with eight-node 3D brick element (SOLID185 3D 8-Node Structural Solid.

  8. Fabrication of fiber-reinforced composites by chemical vapor infiltration

    Besmann, T.M.; Stinton, D.P. [Oak Ridge National Lab., TN (United States); Matlin, W.M.; Liaw, P.K. [Univ. of Tennessee, Knoxville, TN (United States)


    Processing equipment for the infiltration of fiber-reinforced composite tubes is being designed that incorporates improvements over the equipment used to infiltrate disks. A computer-controlled machine-man interface is being developed to allow for total control of all processing variables. Additionally, several improvements are being made to the furnace that will reduce the complexity and cost of the process. These improvements include the incorporation of free standing preforms, cast mandrels, and simpler graphite heating elements.

  9. Fabrication of fiber-reinforced composites by chemical vapor infiltration

    Besmann, T.M.; Matlin, W.M.; Stinton, D.P.; Liaw, P.K.


    Processing equipment for the infiltration of fiber-reinforced composite tubes is being designed that incorporates improvements over the equipment used to infiltrate disks. A computer-controlled machine-man interface is being developed to allow for total control of all processing variables. Additionally, several improvements are being made to the furnace that will reduce the complexity and cost of the process. These improvements include the incorporation of free standing preforms, cast mandrels, and simpler graphite heating elements.

  10. Mechanical performance of oil palm empty fruit bunches/jute fibres reinforced epoxy hybrid composites

    Jawaid, M. [School of Industrial Technology, Universiti Sains Malaysia, 11800 Penang (Malaysia); Abdul Khalil, H.P.S., E-mail: [School of Industrial Technology, Universiti Sains Malaysia, 11800 Penang (Malaysia); Abu Bakar, A. [School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang (Malaysia)


    Research highlights: {yields} Hybrid composites constituents of natural fibres show good mechanical performances. {yields} Hybridization with 20% jute fibre gives rise to sufficient modulus to composites. {yields} Outer or core material affect mechanical performance of hybrid composites. {yields} Impact strength of pure EFB composite is higher than hybrid composites. - Abstract: Oil palm empty fruit bunches (EFB)/jute fibre reinforced epoxy hybrid composites with different sequence of fibre mat arrangement such as EFB/jute/EFB and jute/EFB/jute were fabricated by hand lay-up method. The effect of layering patterns on the mechanical performance of the composites was studied. The hybrid composites are intended for engineering applications as an alternative to synthetic fibre composites. Mechanical performance of hybrid composites were evaluated and compared with the pure EFB, pure jute composites and neat epoxy using flexural and impact testing. The flexural properties of hybrid composite is higher than that of pure EFB composite with respect to the weight fraction of fibre, where as the impact strength of pure EFB composite is much higher than those of hybrid composites. The flexural results were interpreted using sandwich theory. The fracture surface morphology of the impact testing samples of the hybrid composites was performed by scanning electron microscopy (SEM).

  11. Optimal Material Layout - Applied on Reinforced Concrete Slabs

    Dollerup, Niels; Jepsen, Michael S.; Damkilde, Lars


    to determine the optimal material layout of a slab in the ultimate load state, based on simple inputs such as outer geometry, boundary conditions, multiple load cases and design domains. The material layout of the optimal design can either be fully orthotropic or isotropic, or a combination with a predefined......This paper introduces a general, finite-element-based optimisation tool for improving the material layout of concrete structures. The application presented is general and exemplified by material optimisation of reinforced concrete slabs. By utilising the optimisation tool, it is possible...... coupling between design domains and reinforcement directions. The implementation is a lower bound formulation, resulting in a convex optimisation problem that consists of a number of linear constraints from the equilibrium equations and a number of convex non-linear constraints from the yield criteria...

  12. Erosion-resistant composite material

    Finch, C.B.; Tennery, V.J.; Curlee, R.M.

    A highly erosion-resistant composite material is formed of chemical vapor-deposited titanium diboride on a sintered titanium diboride-nickel substrate. This material may be suitable for use in cutting tools, coal liquefaction systems, etc.

  13. NewIn-situ synthesis method of magnesium matrix composites reinforced with TiC particulates

    Zhang Xiuqing


    Full Text Available Magnesium matrix composites reinforced with TiC particulates was prepared using a new in-situ synthesis method of remelting and dilution technique. And measurements were performed on the composites. The results of x ray diffraction (XRD analysis confirmed that TiC particulates were synthesized during the sintering process, and they retained in magnesium matrix composites after the remelting and dilution processing. From the microstructure characterization and electron probe microanalysis (EPMA, we could see that fine TiC particulates distributed uniformly in the matrix material.

  14. Impacts of Temperature Disparity on Surface Modification of Short Jute Fiber-Reinforced Epoxy Composites

    Basak, Reshmi; Choudhury, P. L.; Pandey, K. M.


    Chase for manufacturing composite materials without negotiating on the physio-mechanical performance has been prevailing since long. Short jute fiber-reinforced epoxy based composites are prepared and their mechanical properties have been analyzed. The fibers are peroxide-silane treated under varying conditions of temperature from low to high. Results display that the jute composites set at higher temperature values indicate higher values of mechanical properties compared to those synthesized under lower temperature range. The same can be cited for liquid retaining capacity.

  15. A Review on Tribological Behaviour of Polymeric Composites and Future Reinforcements

    B. Aldousiri


    Full Text Available Many different families of polymers are used in industries and engineering applications. The demands for studying the tribological behaviour of polymers and their composites are recently increased. This article briefs the most recent studies on the tribological behaviour of polymeric materials based on synthetic fibres. It reviews several factors which control the wear and frictional characteristics of such materials, that is, additives, fibres, interfacial adhesion, tribology environment, operating parameters, and composite geometry. In addition to that, new bioreinforcement (fibre is introduced associated with preliminary results. The results showed that there is high potential of replacing the conventional reinforcement with the bioones.

  16. Low Cost Fabrication of Silicon Carbide Based Ceramics and Fiber Reinforced Composites

    Singh, M.; Levine, S. R.


    A low cost processing technique called reaction forming for the fabrication of near-net and complex shaped components of silicon carbide based ceramics and composites is presented. This process consists of the production of a microporous carbon preform and subsequent infiltration with liquid silicon or silicon-refractory metal alloys. The microporous preforms are made by the pyrolysis of a polymerized resin mixture with very good control of pore volume and pore size thereby yielding materials with tailorable microstructure and composition. Mechanical properties (elastic modulus, flexural strength, and fracture toughness) of reaction-formed silicon carbide ceramics are presented. This processing approach is suitable for various kinds of reinforcements such as whiskers, particulates, fibers (tows, weaves, and filaments), and 3-D architectures. This approach has also been used to fabricate continuous silicon carbide fiber reinforced ceramic composites (CFCC's) with silicon carbide based matrices. Strong and tough composites with tailorable matrix microstructure and composition have been obtained. Microstructure and thermomechanical properties of a silicon carbide (SCS-6) fiber reinforced reaction-formed silicon carbide matrix composites are discussed.

  17. Reinforcement Learning Based Web Service Compositions for Mobile Business

    Zhou, Juan; Chen, Shouming

    In this paper, we propose a new solution to Reactive Web Service Composition, via molding with Reinforcement Learning, and introducing modified (alterable) QoS variables into the model as elements in the Markov Decision Process tuple. Moreover, we give an example of Reactive-WSC-based mobile banking, to demonstrate the intrinsic capability of the solution in question of obtaining the optimized service composition, characterized by (alterable) target QoS variable sets with optimized values. Consequently, we come to the conclusion that the solution has decent potentials in boosting customer experiences and qualities of services in Web Services, and those in applications in the whole electronic commerce and business sector.

  18. Analysis of Composite Material Blended With Thermoplastics and Jute Fibre

    Venugopal S


    Full Text Available Recently natural fibres have been receiving considerable attention as substitutes for synthetic fibre reinforcements due to their low cost, low density, acceptable specific strength, good thermal insulation properties, reduced tool wear, reduced thermal and respiratory irritation and renewable resources. The aim of this work is to develop chemically treated and chemically untreated fibre reinforced composite material with optimum properties so that it can replace the existing synthetic fibre reinforced composite material for a suitable application. In this work, polyester resin has been reinforced with jute fabric, so as to develop jute fibre reinforced plastic (JFRP with a weight ratio of 10:1:1 Hand lay-up technique was used to manufacture the composites where Methyl Ethyl Ketone Peroxide and cobalt Naphthalene were used as coupling agent and accelerator respectively. The thickness of the composite specimen was obtained by laying up layer of fibre and matrix. The untreated composites have been used and mechanical properties are compared with natural fibre and jute fibre composite by using the Ansys method.

  19. Manufacturing of Aluminum Composite Material Using Stir Casting Process

    Muhammad Hayat Jokhio


    Full Text Available Manufacturing of aluminum alloy based casting composite materials via stir casting is one of the prominent and economical route for development and processing of metal matrix composites materials. Properties of these materials depend upon many processing parameters and selection of matrix and reinforcements. Literature reveals that most of the researchers are using 2, 6 and 7xxx aluminum matrix reinforced with SiC particles for high strength properties whereas, insufficient information is available on reinforcement of \\"Al2O3\\" particles in 7xxx aluminum matrix. The 7xxx series aluminum matrix usually contains Cu-Zn-Mg. Therefore, the present research was conducted to investigate the effect of elemental metal such as Cu-Zn-Mg in aluminum matrix on mechanical properties of stir casting of aluminum composite materials reinforced with alpha \\"Al2O3\\" particles using simple foundry melting alloying and casting route. The age hardening treatments were also applied to study the aging response of the aluminum matrix on strength, ductility and hardness. The experimental results indicate that aluminum matrix cast composite can be manufactured via conventional foundry method giving very good responses to the strength and ductility up to 10% \\"Al2O3\\" particles reinforced in aluminum matrix.

  20. Approach to microstructure-behavior relationships for ceramic matrix composites reinforced by continuous fibers

    Lamon Jacques


    Full Text Available Ceramic matrix composites (CMCs reinforced with continuous fibers exhibit several features that differentiate them from homogeneous unreinforced materials. The microstructure consists of various distinct constituents: fibres, matrix, and fiber/matrix interfaces or interphases. Several entities at micro- and mesoscopic length scales can be defined depending on fiber arrangement. Furthermore, the CMCs contain flaw populations that govern matrix cracking and fiber failures. The paper describes the microstructure-behavior relations for ceramic matrix composites reinforced with continuous fibers. It focuses on matrix damage by multiple cracking, on ultimate fracture, on delayed fracture at high temperatures, and on stochastic features induced by flaw populations. Models of damage and ultimate failure are based on micromechanics and fracture probabilities. They provide a basis for a multiscale approach to composite and component design.

  1. Environment Friendly Composite Materials: Biocomposites and Green Composites

    B. C. Mitra


    Full Text Available Biocomposites can supplement and eventually replace petroleum-based composite materials in several applications. Several critical issues related to bio-fiber surface treatments is to make it a more suitable matrix for composite application and promising techniques need to be solved to design biocomposite of interest. The main motivation for developing biocomposites has been and still is to create a new generation of fiber reinforced plastics material competitive with glass fiber reinforced ones which are environmentally compatible in terms of products, use and renewal. There is an immense opportunity in developing new biobased products, but the real challenge isto design suitable bio-based products through innovation ideas. Green materials are the wave of the future. Bionanocomposites have very strong future prospects, though the present low level of production, some deficiency intechnology and high cost restrict them from a wide range of applications.Defence Science Journal, Vol. 64, No. 3, May 2014, pp. 244-261, DOI:

  2. Preliminary Study of the Influence of Post Curing Parameters to the Particle Reinforced Composite's Mechanical and Physical Properties

    Aare ARUNIIT; Jaan KERS; Andres KRUMME; Triinu POLTIMÄE; Kaspar TALL


    This study examines the effect of different post cure parameters to a polymer matrix particulate reinforced composite material. The goal is to evaluate the importance of different factors and to suggest a well-balanced post cure mode that supports the application of the material.Polymer matrix composites are post cured at elevated temperature to increase the amount of cross linking to achieve better chemical and heat resistance and mechanical properties. Every material has an individual post ...

  3. Kevlar-129纤维复合材料的弹道侵彻数值仿真%Ballistic impact simulation of Kevlar-1 29 fiber reinforced composite material

    张明; 原梅妮; 向丰华; 王振兴


    The penetration resistance of Kevlar-129 fiber reinforced composite materials was investigated with AUTODYN soft-ware.The ballistic limits of the fragment that pierced 6 kinds of target plates were obtained by finite element simulation when the 10 g fragment simulation projectile (FSP)impacting to the target plates of different thickness values of 8,10,12,14,16 and 1 8 mm with appropriate velocity,respectively,and the influences of thickness on the ballistic limits and the specific energy absorption were analyzed.The results show that the ballistic limit of Kevlar-129 fiber reinforced composite plates presents line-ar growth with the increase of the target thickness in the range from 8 to 1 8 mm.The specific energy absorption of plates pres-ents approximately linear growth,but there is slightly slow growth in the range from 10 to 16 mm of the target thickness.It al-so can be found that the influences of plate thickness and surface density on the varying pattern of specific energy absorption are almost the same.Therefore,both of them can be used to characterize the variation of specific energy absorption under the im-pact of the FSP fragment.%基于 AUTODYN有限元软件,研究了Kevlar-129纤维增强复合材料的抗侵彻性能。通过质量为10 g的 FSP破片对厚度为8、10、12、14、16以及18 mm 的六组 Kevlar 纤维靶板进行撞击模拟,获得了 FSP破片贯穿6组靶板的弹道极限,并分析了靶板的弹道极限、比吸收能随板厚的变化关系。结果表明,在板厚8-18 mm范围内,Kevlar纤维靶板的弹道极限随板厚的增加呈线性增长;在此范围内,靶板的比吸收能也呈近似线性增长,但在板厚为10-16 mm时,增长稍缓。对比还发现,比吸收能随板厚的变化规律与靶板面密度的变化规律几乎相同,二者都可用于描述Kevlar-129纤维复合材料靶板在 FSP 破片碰撞下比吸收能的变化。

  4. Fiber reinforced silicon-containing arylacetylene resin composites


    Full Text Available A silicon-containing arylacetylene resin (SAR, a poly(dimethylsilyleneethynylene phenyleneethynylene (PMSEPE, was synthesized. The PMSEPE is a solid resin at ambient temperature with a softening temperature about 60°C and soluble in some solvents like tetrahydrofuran. The melt viscosity of the PMSEPE resin is less than 1 Pa•s. The resin could cure at the temperature of lower than 200°C. Fiber reinforced PMSEPE composites were prepared from prepregs which were made by the impregnation of fibers in PMSEPE resin solution. The composites exhibit good mechanical properties at room temperature and 250°C. The observation on fracture surfaces of the composites reinforced by glass fibers and carbon fibers demonstrates that the adhesion between the fibers and resin is good. The results from an oxyacetylene flame test show that the composites have good ablation performance and XRD analyses indicate that SiC forms in the residues during the ablation of the composites.

  5. Composite Materials for Structural Design.


    Introduction to Composite Materials , Technomic, Westport, Connecticut, 1980, pp. 19-20, 388-401. 8. W.D. Bascom, J.L. Bitner, R.J. Moulton, and A.R. Siebert...34 Introduction to Composite Materials ", Technomic Publishing Co., pp. 8-18,(1980). [6] Beckwith, S. W., "Viscoelastic Characterization of a Nonlinear Glass

  6. Microbiological specifics of the phosphate removal systems with the help of reinforced materials

    Ruzhitskaya Ol’ga Andreevna


    Full Text Available The author presents the results of microbiological studies aimed at investigating the deep removal of phosphates from household wastewater. A method for deep cleaning of waste water using reinforced materials is provided. The living culture study in activated sludge and biofilm in the light microscope showed activating effect of the reinforced loading material on the life of microflora in activated sludge and biofilm. A steel wire in the the feed material has a significant impact on the number and variety of species of protozoa in the activated sludge, and also leads to rapid development of Chlorella sp. The study of the living culture of activated sludge and biofilm in the light microscope showed that the reinforced material activates the vital functions of the activated sludge microflora and biofilms, as well as the diversity of their species composition. The studies have confirmed that chlorella multiplies in an environment rich with iron, absorbs phosphorus from the environment and actively produces oxygen, providing bacterial biomass with it. This fact explains the increase in the removal of organic contaminants, as well as the influence of the reinforced material on the second step of nitrification.

  7. Composite Materials in Overhead Lines

    Sørensen, Thomas Kjærsgaard; Holbøll, Joachim


    The use of composite materials, e.g. fibreglass materials, in overhead transmission line systems is nothing new. Composite based insulators have been applied to transmission lines for over 30 years, mainly as suspension and post insulators and often as an option for special applications. Also...... towers and recently conductors based on composite materials are available at transmission levels. In this paper it is investigated which composite based solutions are available in connection with complete overhead line systems including insulators, towers and conductors. The components are reviewed...... with respect to solved and persisting known failures/problems of both mechanical and electrical nature. Major challenges related to extensive use of composite materials in an overhead line system are identified, as are possible benefits - both when using standard as well as customised composite components, e...

  8. The study of mechanical properties of pineapple leaf fibre reinforced tapioca based bioplastic resin composite

    Mathivanan D.


    Full Text Available Natural fibre reinforced composite has brought the material engineering to a high new level of research. Natural fibres are compatible with matrices like polypropylene and can be used as reinforcement material to reduce the composition of plastic in a material. Natural fibres such as kenaf, pineapple leaf, and coir already found its importance in reducing the dependence of petroleum based products. However the biodegradability of the product at the end of the intended lifespan is still questionable. This has led many researches to look for a suitable replacement for synthetic fibres and achieve better adhesion between fibre and matrix. In this study, fiber and matrix which are hydrophilic in nature was used and the mixture was extruded and hot compressed to acquire better mechanical properties. The specimens were fabricated and tested according to ASTM D638. The 30% composition illustrates the best average modulus value among other composition and from this result it can be concluded that the increase of PALF fibre in TBR composite increases the modulus strength of the composite.

  9. An experimental investigation into the trapping model core pillars with reinforced fly ash composites

    Mishra, M.K. [National Inst. of Technology, Rourkela (India); Karanam, U.M. [Indian Inst. of Technology, Kharagpur (India)


    This paper presented details of a study which examined the use of fly ash composite materials for backfilling mine voids in room-and-pillar mining techniques. The study examined the load deformation characteristics of model core pillars confined by wire mesh reinforced fly ash composite materials. Anhydrous chemical-grade lime and gypsum were added in various quantities to class F fly ash samples. The model core pillars were 57 mm in diameter and 200 mm in length. The engineering properties of the model core pillars were then determined using unconfined compressive strength and Brazilian indirect tensile strength tests. The experimental investigations showed that the percentage increases in the strength of the trapped model core pillars varied with the different types of composite materials, and was also influenced by the length of the curing period and the ratio of the annular thickness of the fill area to the model core pillar radius. Results demonstrated that the addition of excess lime to fly ash composites was not beneficial. Maximum strength gains of 14 per cent were achieved with model cores of a cement-sand ratio of 1:2.5 for fly ash composites containing 15 per cent lime and 5 per cent gypsum. It was concluded that suitable fly ash composites reinforced with wire ropes can enhance the strength of the load bearing element and alter the post-peak characteristics of trapped cores.

  10. Conductive Behaviors of Carbon Nanofibers Reinforced Epoxy Composites

    MEI Qilin; WANG Jihui; WANG Fuling; HUANG Zhixiong; YANG Xiaolin; WEI Tao


    By means of ultrasonic dispersion,carbon nanofibers reinforced epoxy resin composite was prepared in the lab,the electrical conductivity of composite with different carbon nanofibers loadings were studied,also the voltage-current relationship,resistance-temperature properties and mechano-electric effect were investigated.Results show that the resistivity of composite decreases in geometric progression with the increasing of carbon nanofibers,and the threshold ranges between 0.1 wt%-0.2 wt%.The voltage-current relationship is in good conformity with the Ohm's law,both positive temperature coefficient and negative temperature coefficient can be found at elevated temperature.In the course of stretching,the electrical resistance of the composites increases with the stress steadily and changes sharply near the breaking point,which is of importance for the safety monitor and structure health diagnosis.

  11. Progress in Research on Carbon Nanotubes Reinforced Cementitious Composites

    Qinghua Li


    Full Text Available As one-dimensional (1D nanofiber, carbon nanotubes (CNTs have been widely used to improve the performance of nanocomposites due to their high strength, small dimensions, and remarkable physical properties. Progress in the field of CNTs presents a potential opportunity to enhance cementitious composites at the nanoscale. In this review, current research activities and key advances on multiwalled carbon nanotubes (MWCNTs reinforced cementitious composites are summarized, including the effect of MWCNTs on modulus of elasticity, porosity, fracture, and mechanical and microstructure properties of cement-based composites. The issues about the improvement mechanisms, MWCNTs dispersion methods, and the major factors affecting the mechanical properties of composites are discussed. In addition, large-scale production methods of MWCNTs and the effects of CNTs on environment and health are also summarized.

  12. Mechanical properties of pineapple leaf fibre reinforced polypropylene composites

    Arib, R.M.N. [Department of Mechanical and Manufacturing Engineering, Universiti Putra Malaysia, 43400 Serdang, Selangor (Malaysia); Sapuan, S.M. [Department of Mechanical and Manufacturing Engineering, Universiti Putra Malaysia, 43400 Serdang, Selangor (Malaysia)]. E-mail:; Ahmad, M.M.H.M. [Department of Mechanical and Manufacturing Engineering, Universiti Putra Malaysia, 43400 Serdang, Selangor (Malaysia); Paridah, M.T. [Faculty of Forestry, Universiti Putra Malaysia, 43400 Serdang, Selangor (Malaysia); Zaman, H.M.D. Khairul [Radiation Processing Technology Division, Malaysian Institute for Nuclear Technology Research (MINT), Bangi 43000 Kajang, Selangor (Malaysia)


    Pineapple leaf fibre, which is rich in cellulose, relative inexpensive and abundantly available has the potential for polymer-reinforced composite. The present study investigates the tensile and flexural behaviours of pineapple leaf fibre-polypropylene composites as a function of volume fraction. The tensile modulus and tensile strength of the composites were found to be increasing with fibre content in accordance with the rule of mixtures. The tensile modulus and tensile strength with a volume fraction 10.8% are 687.02 and 37.28 MPa, respectively. The flexural modulus gives higher value at 2.7% volume fraction. The flexural strength of the composites containing 5.4% volume fraction was found to be higher than that of pure polypropylene resin by 5.1%. Scanning electron microscopic studies were carried out to understand the fibre-matrix adhesion and fibre breakage.

  13. Objective Surface Evaluation of Fiber Reinforced Polymer Composites

    Palmer, Stuart; Hall, Wayne


    The mechanical properties of advanced composites are essential for their structural performance, but the surface finish on exterior composite panels is of critical importance for customer satisfaction. This paper describes the application of wavelet texture analysis (WTA) to the task of automatically classifying the surface finish properties of two fiber reinforced polymer (FRP) composite construction types (clear resin and gel-coat) into three quality grades. Samples were imaged and wavelet multi-scale decomposition was used to create a visual texture representation of the sample, capturing image features at different scales and orientations. Principal components analysis was used to reduce the dimensionality of the texture feature vector, permitting successful classification of the samples using only the first principal component. This work extends and further validates the feasibility of this approach as the basis for automated non-contact classification of composite surface finish using image analysis.

  14. Experimental Test of Stainless Steel Wire Mesh and Aluminium Alloy With Glass Fiber Reinforcement Hybrid Composite


    At present, composite materials are mostly used in aircraft structural components, because of their excellent properties like lightweight, high strength to weight ratio, high stiffness, and corrosion resistance and less expensive. In this experimental work, the mechanical properties of laminate, this is reinforced with stainless steel wire mesh, aluminum sheet metal, perforated aluminum sheet metal and glass fibers to be laminate and investigated. The stainless steel wire mesh and...

  15. Basalt fiber reinforced porous aggregates-geopolymer based cellular material

    Luo, Xin; Xu, Jin-Yu; Li, Weimin


    Basalt fiber reinforced porous aggregates-geopolymer based cellular material (BFRPGCM) was prepared. The stress-strain curve has been worked out. The ideal energy-absorbing efficiency has been analyzed and the application prospect has been explored. The results show the following: fiber reinforced cellular material has successively sized pore structures; the stress-strain curve has two stages: elastic stage and yielding plateau stage; the greatest value of the ideal energy-absorbing efficiency of BFRPGCM is 89.11%, which suggests BFRPGCM has excellent energy-absorbing property. Thus, it can be seen that BFRPGCM is easy and simple to make, has high plasticity, low density and excellent energy-absorbing features. So, BFRPGCM is a promising energy-absorbing material used especially in civil defense engineering.

  16. Size-effects on yield surfaces for micro reinforced composites

    Azizi, Reza; Niordson, Christian Frithiof; Legarth, Brian Nyvang


    of the plastic strain tensor appear as free variables in addition to the displacement variables. Non-conventional boundary conditions are applied at material interfaces to model a constraint on plastic flow due to dislocation blocking. Unit cell calculations are carried out under generalized plane strain...... conditions. The homogenized response of a material with cylindrical reinforcing fibers is analyzed for different values of the internal material length scale and homogenized yield surfaces are presented. While the main focus is on initial yield surfaces, subsequent yield surfaces are also presented...

  17. Superconducting composites materials. Materiaux composites supraconducteurs

    Kerjouan, P.; Boterel, F.; Lostec, J.; Bertot, J.P.; Haussonne, J.M. (Centre National d' Etudes des Telecommunications (CNET), 22 - Lannion (FR))


    The new superconductor materials with a high critical current own a large importance as well in the electronic components or in the electrotechnical devices fields. The deposit of such materials with the thick films technology is to be more and more developed in the years to come. Therefore, we tried to realize such thick films screen printed on alumina, and composed mainly of the YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} material. We first realized a composite material glass/YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}, by analogy with the classical screen-printed inks where the glass ensures the bonding with the substrate. We thus realized different materials by using some different classes of glass. These materials owned a superconducting transition close to the one of the pure YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} material. We made a slurry with the most significant composite materials and binders, and screen-printed them on an alumina substrate preliminary or not coated with a diffusion barrier layer. After firing, we studied the thick films adhesion, the alumina/glass/composite material interfaces, and their superconducting properties. 8 refs.; 14 figs.; 9 tabs.

  18. Fatigue of multiscale composites with secondary nanoplatelet reinforcement: 3D computational analysis

    Dai, Gaoming; Mishnaevsky, Leon, Jr.


    3D numerical simulations of fatigue damage of multiscale fiber reinforced polymer composites with secondary nanoclay reinforcement are carried out. Macro–micro FE models of the multiscale composites are generated automatically using Python based software. The effect of the nanoclay reinforcement...

  19. Strain-Detecting Composite Materials

    Wallace, Terryl A. (Inventor); Smith, Stephen W. (Inventor); Piascik, Robert S. (Inventor); Horne, Michael R. (Inventor); Messick, Peter L. (Inventor); Alexa, Joel A. (Inventor); Glaessgen, Edward H. (Inventor); Hailer, Benjamin T. (Inventor)


    A composite material includes a structural material and a shape-memory alloy embedded in the structural material. The shape-memory alloy changes crystallographic phase from austenite to martensite in response to a predefined critical macroscopic average strain of the composite material. In a second embodiment, the composite material includes a plurality of particles of a ferromagnetic shape-memory alloy embedded in the structural material. The ferromagnetic shape-memory alloy changes crystallographic phase from austenite to martensite and changes magnetic phase in response to the predefined critical macroscopic average strain of the composite material. A method of forming a composite material for sensing the predefined critical macroscopic average strain includes providing the shape-memory alloy having an austenite crystallographic phase, changing a size and shape of the shape-memory alloy to thereby form a plurality of particles, and combining the structural material and the particles at a temperature of from about C. to form the composite material.

  20. Development and characterization of 430L matrix composites gradient materials

    Elisa Maria Ruiz-Navas


    Full Text Available This paper deals with a new concept that is Functionally Gradient Materials (FGM. The materials developed in this work are constituted by a 430L matrix core and composite materials with this matrix and gradient concentration with NbC reinforcement, from the core to the surface, through different steps. Composite powders of different content in NbC were produced through high energy milling in order to obtain the gradient composition. The morphology and microhardness of these powders were characterised and subsequently were processed through conventional P/M techniques, pressing and sintering. The materials obtained show improved wear behaviour.

  1. ECAP – New consolidation method for production of aluminium matrix composites with ceramic reinforcement

    Mateja Šnajdar Musa


    Full Text Available Aluminium based metal matrix composites are rapidly developing group of materials due to their unique combination of properties that include low weight, elevated strength, improved wear and corrosion resistance and relatively good ductility. This combination of properties is a result of mixing two groups of materials with rather different properties with aluminium as ductile matrix and different oxides and carbides added as reinforcement. Al2O3, SiC and ZrO2 are the most popular choices of reinforcement material. One of the most common methods for producing this type of metal matrix composites is powder metallurgy since it has many variations and also is relatively low-cost method. Many different techniques of compacting aluminium and ceramic powders have been previously investigated. Among those techniques equal channel angular pressing (ECAP stands out due to its beneficial influence on the main problem that arises during powder compaction and that is a non-uniform distribution of reinforcement particles. This paper gives an overview on ECAP method principles, advantages and produced powder composite properties.

  2. Reliable non-destructive inspection of composite materials in use in the aviation industry

    Johannes, Manfred


    Full Text Available Fibre reinforced composite materials are increasingly being used in engineering applications in the aircraft industry as they display an excellent weight to strength ratio. The limitation on the use of these materials in load-bearing applications...

  3. Properties and Microstructure of Polymer Emulsions Modified Fibers Reinforced Cementitious Composites

    WU Ying; SUN Qianyao; KONG Lian; FANG He


    The synthesis and characterization of a new class of cementitious composites filled with polymer emulsions were investigated, and their superior mechanical strength and durability properties compared to composites devoid of fillers were reported. Polymer emulsions were utilized to mechanically reinforce the composite and bridge the cement, fly ash, aggregate and fibers. The results reveal that the epoxy emulsion and poly (ethylene-co-vinyl acetate) emulsion markedly enhance the mechanical and durability properties of cemetitious composites. The fibers can be pulled out in the form of slip-hardening and the abrasion phenomenon can be observed clearly on the surface of the fibers. The hydration extent of cement is higher than that of the pristine composites. The polymer modified cementitious composites designed on micromechanics, have flexibility and plasticity which could be applied for a novel form of multifunctional materials with a range of pipeline coatings applications.

  4. Recycling of asbestos tailings used as reinforcing fillers in polypropylene based composites.

    Zhai, Wensi; Wang, Yao; Deng, Yuan; Gao, Hongli; Lin, Zhen; Li, Mao


    In this work, asbestos tailings were recycled and used as reinforcing fillers to enhance the mechanical properties of polypropylene (PP). A silane coupling agent was used to chemically modify the asbestos tailings to increase the compatibility between asbestos tailings and polypropylene matrix. Both raw and chemically treated asbestos tailings with different loading levels (from 3 to 30 wt%) were utilized to fabricate composites. Mechanical properties of these composites have been investigated by dynamic mechanical analysis, tensile test and notched impact test. Results showed that hybridization of asbestos tailings in the composites enhanced the mechanical properties of neat PP evidently, and treated asbestos tailings/PP composites yielded even better mechanical properties compared with those of raw asbestos tailings/PP composites. This recycling method of asbestos tailings not only reduces disposal costs and avoids secondary pollution but also produces a new PP-based composite material with enhanced mechanical properties.


    Andrzej Skrzat


    Full Text Available The determination of effective mechanical properties of multi-layer composite is presented in this paper. Computations based on finite element method predicting properties of inhomogeneous materials require solving huge tasks. More effective is Mori-Tanaka approach, typical for micromechanics problems. For regularly distributed fibers closed-forms for effective composite material properties are possible to derive. The results of homogenization are used in strength analysis of the composite pressure vessel.

  6. Study of the stress-strain state of compressed concrete elements with composite reinforcement

    Bondarenko Yurii


    Full Text Available The efficiency analysis of the application of glass composite reinforcement in compressed concrete elements as a load-carrying component has been performed. The results of experimental studies of the deformation-strength characteristics of this reinforcement on compression and compressed concrete cylinders reinforced by this reinforcement are presented. The results of tests and mechanisms of sample destruction have been analyzed. The numerical analysis of the stress-strain state has been performed for axial compression of concrete elements with glasscomposite reinforcement. The influence of the reinforcement percentage on the stressed state of a concrete compressed element with the noted reinforcement is estimated. On the basis of the obtained results, it is established that the glass-composite reinforcement has positive effect on the strength of the compressed concrete elements. That is, when calculating the load-bearing capacity of such structures, the function of composite reinforcement on compression should not be neglected.

  7. Carbon Fiber Reinforced Polymer with Shredded Fibers: Quasi-Isotropic Material Properties and Antenna Performance

    Gerald Artner; Philipp K. Gentner; Johann Nicolics; Mecklenbräuker, Christoph F.


    A carbon fiber reinforced polymer (CFRP) laminate, with the top layer consisting of shredded fibers, is proposed and manufactured. The shredded fibers are aligned randomly on the surface to achieve a more isotropic conductivity, as is desired in antenna applications. Moreover, fiber shreds can be recycled from carbon fiber composites. Conductivity, permittivity, and permeability are obtained with the Nicolson-Ross-Weir method from material samples measured inside rectangular waveguides in the...

  8. New Polylactic Acid Composites Reinforced with Artichoke Fibers

    Luigi Botta


    Full Text Available In this work, artichoke fibers were used for the first time to prepare poly(lactic acid (PLA-based biocomposites. In particular, two PLA/artichoke composites with the same fiber loading (10% w/w were prepared by the film-stacking method: the first one (UNID reinforced with unidirectional long artichoke fibers, the second one (RANDOM reinforced by randomly-oriented long artichoke fibers. Both composites were mechanically characterized in tensile mode by quasi-static and dynamic mechanical tests. The morphology of the fracture surfaces was analyzed through scanning electron microscopy (SEM. Moreover, a theoretical model, i.e., Hill’s method, was used to fit the experimental Young’s modulus of the biocomposites. The quasi-static tensile tests revealed that the modulus of UNID composites is significantly higher than that of the neat PLA (i.e., ~40%. Moreover, the tensile strength is slightly higher than that of the neat matrix. The other way around, the stiffness of RANDOM composites is not significantly improved, and the tensile strength decreases in comparison to the neat PLA.

  9. Carbon nanofiber reinforced epoxy matrix composites and syntactic foams - mechanical, thermal, and electrical properties

    Poveda, Ronald Leonel

    The tailorability of composite materials is crucial for use in a wide array of real-world applications, which range from heat-sensitive computer components to fuselage reinforcement on commercial aircraft. The mechanical, electrical, and thermal properties of composites are highly dependent on their material composition, method of fabrication, inclusion orientation, and constituent percentages. The focus of this work is to explore carbon nanofibers (CNFs) as potential nanoscale reinforcement for hollow particle filled polymer composites referred to as syntactic foams. In the present study, polymer composites with high weight fractions of CNFs, ranging from 1-10 wt.%, are used for quasi-static and high strain rate compression analysis, as well as for evaluation and characterization of thermal and electrical properties. It is shown that during compressive characterization of vapor grown carbon nanofiber (CNF)/epoxy composites in the strain rate range of 10-4-2800 s-1, a difference in the fiber failure mechanism is identified based on the strain rate. Results from compression analyses show that the addition of fractions of CNFs and glass microballoons varies the compressive strength and elastic modulus of epoxy composites by as much as 53.6% and 39.9%. The compressive strength and modulus of the syntactic foams is also shown to generally increase by a factor of 3.41 and 2.96, respectively, with increasing strain rate when quasi-static and high strain rate testing data are compared, proving strain rate sensitivity of these reinforced composites. Exposure to moisture over a 6 month period of time is found to reduce the quasi-static and high strain rate strength and modulus, with a maximum of 7% weight gain with select grades of CNF/syntactic foam. The degradation of glass microballoons due to dealkalization is found to be the primary mechanism for reduced mechanical properties, as well as moisture diffusion and weight gain. In terms of thermal analysis results, the

  10. 预测纤维增强气凝胶复合材料热导率的研究进展∗%Predicting Thermal Conductivity of Fiber-reinforced Aerogel Composite Materials

    杨建明; 吴会军; 王沫然


    SiO2气凝胶复合材料具有纳米尺度结构和极低热导率,作为隔热保温材料在航天航空、建筑和其他工业领域具有重要的科学和应用价值。根据纤维在气凝胶基体中的不同分布方式,概述了预测 SiO2气凝胶复合材料的气固耦合热导率的研究进展;基于纤维和气凝胶的消光系数的不同计算方法,概述了预测 SiO2气凝胶复合材料的辐射热导率的研究进展。并提出了纤维增强气凝胶复合材料体系存在的跨尺度、多物相、分级及相互耦合等仍需进一步解决的难题,结合最新发展的格子 Boltzmann 方法(LBM),指出了预测 SiO2气凝胶复合材料等效热导率的可能发展方向。%SiO2 aerogel composites with nano-scale structure and very low thermal conductivity have widely been used in aeronautics and astronautics,construction and other industries for thermal insulations.The research de-velopment in the conductive thermal conductivity of the SiO2 aerogel composites are reviewed according to the various distribution modes of reinforced fibers in aerogel matrix.Based on the calculation methods of the extinction coefficients of aerogels and fiber reinforcements,the advances in the radiative thermal conductivity of the SiO2 aerogel composites are demonstrated.The existing difficulties in predicting the effective thermal conductivity of the SiO2 aerogel compo-sites are generalized relevant to the cross scale,multiphase,classification and interconnection in the fiber-reinforced SiO2 aerogel composites.The perspective of the accurate prediction of the effective thermal conductivity of SiO2 aero-gel composites is also proposed involving a newly developed method - lattice Boltzmann method.

  11. A Study of Nanoclay Reinforcement of Biocomposites Made by Liquid Composite Molding

    Farida Bensadoun


    Full Text Available Liquid composite molding (LCM processes are widely used to manufacture composite parts for the automotive industry. An appropriate selection of the materials and proper optimization of the manufacturing parameters are keys to produce parts with improved mechanical properties. This paper reports on a study of biobased composites reinforced with nanoclay particles. A soy-based unsaturated polyester resin was used as synthetic matrix, and glass and flax fiber fabrics were used as reinforcement. This paper aims to improve mechanical and flammability properties of reinforced composites by introducing nanoclay particles in the unsaturated polyester resin. Four different mixing techniques were investigated to improve the dispersion of nanoclay particles in the bioresin in order to obtain intercalated or exfoliated structures. An experimental study was carried out to define the adequate parameter combinations between vacuum pressure, filling time, and resin viscosity. Two manufacturing methods were investigated and compared: RTM and SCRIMP. Mechanical properties, such as flexural modulus and ultimate strength, were evaluated and compared for conventional glass fiber composites (GFC and flax fiber biocomposites (GFBiores-C. Finally, smoke density analysis was performed to demonstrate the effects and advantages of using an environment-friendly resin combined with nanoclay particles.

  12. Mechanics in Composite Materials and Process

    Lee, Dae Gil


    This book includes introduction of composite materials, stress, in-plane stiffness of laminates strain rate, ply stress, failure criterion and bending, composite materials micromechanics, composite plates and micromechanics of composite materials. It also deals with process of composite materials such as autoclave vacuum bag degassing process, connection of composite materials, filament winding process, resin transfer molding, sheet molding compound and compression molding.

  13. Investigations of sewn preform characteristics and quality aspects for the manufacturing of fiber reinforced polymer composites

    Ogale, Amol


    Sewn net-shape preform based composite manufacturing technology is widely accepted in combination with liquid composite molding technologies for the manufacturing of fiber reinforced polymer composites. The development of threedimensional dry fibrous reinforcement structures containing desired fiber orientation and volume fraction before the resin infusion is based on the predefined preforming processes. Various preform manufacturing aspects influence the overall composite m...

  14. Dynamic fracture behaviour in fibre-reinforced cementitious composites

    Yu, Rena C.; Cifuentes, Héctor; Rivero, Ignacio; Ruiz, Gonzalo; Zhang, Xiaoxin


    The object of this work is to simulate the dynamic fracture propagation in fibre-reinforced cementitious composites, in particular, in steel fibre reinforced concrete (SFRC). Beams loaded in a three-point bend configuration through a drop-weight impact device are considered. A single cohesive crack is assumed to propagate at the middle section; the opening of this crack is governed by a rate-dependent cohesive law; the fibres around the fracture plane are explicitly represented through truss elements. The fibre pull-out behaviour is depicted by an equivalent constitutive law, which is obtained from an analytical load-slip curve. The obtained load-displacement curves and crack propagation velocities are compared with their experimental counterparts. The good agreement with experimental data testifies to the feasibility of the proposed methodology and paves the way to its application in a multi-scale framework.


    Mr. Khosen ф Ri


    Full Text Available The authors study obtaining a composite material NiAl - Mo2B5 while carrying out thermally coupled reactions of self-propagating high-temperature synthesis with a deoxidizing aluminothermal stage. The authors established ultimate and phase composition of the obtained composite. The microstructure is studied. It is shown that the composite consists of the intermetallic phase NiAl with Mo2B5 inclusions.

  16. Automobile materials competition: energy implications of fiber-reinforced plastics

    Cummings-Saxton, J.


    The embodied energy, structural weight, and transportation energy (fuel requirement) characteristics of steel, fiber-reinforced plastics, and aluminum were assessed to determine the overall energy savings of materials substitution in automobiles. In body panels, a 1.0-lb steel component with an associated 0.5 lb in secondary weight is structurally equivalent to a 0.6-lb fiber-reinforced plastic component with 0.3 lb in associated secondary weight or a 0.5-lb aluminum component with 0.25 lb of secondary weight. (Secondary weight refers to the combined weight of the vehicle's support structure, engine, braking system, and drive train, all of which can be reduced in response to a decrease in total vehicle weight.) The life cycle transportation energy requirements of structurally equivalent body panels (including their associated secondary weights) are 174.4 x 10/sup 3/ Btu for steel, 104.6 x 10/sup 3/ Btu for fiber-reinforced plastics, and 87.2 x 10/sup 3/ Btu for aluminum. The embodied energy requirements are 37.2 x 10/sup 3/ Btu for steel, 22.1 x 10/sup 3/ Btu for fiber-reinforced plastics, and 87.1 x 10/sup 3/ Btu for aluminum. These results can be combined to yield total energy requirements of 211.6 x 10/sup 3/ Btu for steel, 126.7 x 10/sup 3/ Btu for fiber-reinforced plastics, and 174.3 x 10/sup 3/ Btu for aluminum. Fiber-reinforced plastics offer the greatest improvements over steel in both embodied and total energy requirements. Aluminum achieves the greatest savings in transportation energy.

  17. Mechanical property analysis of kenaf–glass fibre reinforced polymer composites using finite element analysis

    M Ramesh; S Nijanthan


    Nowadays, natural fibres are used as a reinforcing material in polymer composites, owing to severe environmental concerns. Among many different types of natural resources, kenaf plants have been extensively exploited over the past few years. In this experimental study, partially eco-friendly hybrid composites were fabricated by using kenaf and glass fibres with two different fibre orientations of 0° and 90°. The mechanical properties such as tensile, flexural and impact strengths of these composites have been evaluated. From the experiment, it was observed that the composites with the 0° fibre orientation can withstand the maximum tensile strength of 49.27 MPa, flexural strength of 164.35 MPa, and impact strength of 6 J. Whereas, the composites with the 90° fibre orientation hold the maximum tensile strength of 69.86 MPa, flexural strength of 162.566 MPa and impact strength of 6.66 J. The finite element analysis was carried out to analyse the elastic behaviour of the composites and to predict the mechanical properties by using NX Nastran 9.0 software. The experimental results were compared with the predicted values and a high correlation between the results was observed. The morphology of the fractured surfaces of the composites was analysed using a scanning electron microscopy analysis. The results indicated that the properties were in the increasing trend and comparable with pure synthetic fibre reinforced composites, which shows the potential for hybridization of kenaf fibre with glass fibre.

  18. Structural and thermophysical properties characterization of continuously reinforced cast Al matrix composite

    Brian Gordon


    Full Text Available In this work the process of manufacturing a continuously reinforced cast Al matrix composite and its properties are presented. The described technology permits obtaining a structural material of competitive properties compared to either heat treatable aluminum alloys or polymer composites for several types of applications. The examined thermophysical properties and structural characterization, including material anisotropy, coupled with the results of previous measurements of the mechanical properties of both Al2O3 reinforcing filaments and metallic prepregs have proven the high quality of this material and the possibility of its operation under special loading modes and environmental conditions. Microscopic examinations (LM, SEM were carried out to reveal the range of morphological homogeneity of the microstructure, the anisotropy of the filament band distribution, and simultaneously the adhesive behavior of the metal/fiber interface. The 3D morphology of the chosen microstructure components was revealed by computed tomography. The obtained results indicate that special properties of the examined prepreg materials have been strongly influenced, on the one hand, by the geometry of its internal microstructure, i.e. spatial distribution and volume fraction of the Al2O3 reinforcing filaments and, on the other hand, by a very good compatibility obtained between the individual metal prepreg components.

  19. Hydrophobicity, surface tension, and zeta potential measurements of glass-reinforced hydroxyapatite composites.

    Lopes, M A; Monteiro, F J; Santos, J D; Serro, A P; Saramago, B


    Wettability and zeta potential studies were performed to characterize the hydrophobicity, surface tension, and surface charge of P2O5-glass-reinforced hydroxyapatite composites. Quantitative phase analysis was performed by the Rietveld method using GSAS software applied to X-ray diffractograms. Surface charge was assessed by zeta potential measurements. Protein adsorption studies were performed using vitronectin. Contact angles and surface tensions variation with time were determined by the sessile and pendent drop techniques, respectively, using ADSA-P software. The highest (-18.1 mV) and lowest (-28.7 mV) values of zeta potential were found for hydroxyapatite (HA) and beta-tricalcium phosphate (beta-TCP), respectively, with composite materials presenting values in between. All studied bioceramic materials showed similar solid surface tension. For HA and beta-TCP, solid surface tensions of 46.7 and 45.3 mJ/m2, respectively, were obtained, while composites presented intermediate surface tension values. The dispersive component of surface tension was the predominant one for all materials studied. Adhesion work values between the vitronectin solution and HA and beta-TCP were found to be 79.8 and 88.0 mJ/m2, respectively, while the 4.0 wt % glass composites showed slightly lower values than the 2.5 wt % ones. The presence of beta-TCP influenced surface charge, hydrophobicity, and protein adsorption of the glass-reinforced HA composites, and therefore indirectly affected cell-biomaterial interactions.

  20. Drilling analysis of coir–fibre-reinforced polyester composites

    S Jayabal; U Natarajan


    An investigation has been carried out to make use of coir, a natural fibre abundantly available in India. Coir–polyester composites were prepared and their mechanical and machinability characteristics were studied. The short coir–fibre-reinforced composites exhibited the tensile, flexural and impact strength of 16.1709 MPa, 29.2611 MPa and 46.1740 J/m, respectively. The regression equations were developed and optimized for studying drilling characteristics of coir–polyester composites using the Taguchi approach. A drill bit diameter of 6 mm, spindle speed of 600 rpm and feed rate of 0.3 mm/rev gave the minimum value of thrust force, torque and tool wear in drilling analysis.