Journal articles: 'Composites systems'

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Kedward, K. T., and P. W. R. Beaumont. "The treatment of Fatigue and Damage Accumulation in Composite Design." Advanced Composites Letters 1, no. 4 (July 1992): 096369359200100. http://dx.doi.org/10.1177/096369359200100404.

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SUMMARY The process of design has traditionally involved a specialized treatment of damage accumulation and associated fatigue phenomena, e.g. Miners Rule. The treatment of such phenomena for the case of advanced composites tends to be complicated by the existence of a multiplicity of competing failure modes. The subject assumes even greater importance when the ever expanding types of composite systems are considered, i.e. Polymer Matrix Composites (PMC's), Ceramic Matrix Composites (CMC's) and Metal Matrix Composites (MMC's) to name the broader categories. All composite systems are considered herein to comprise continuous fiber reinforcements.

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Pędzich, Zbigniew. "Fracture of Oxide Matrix Composites with Different Phase Arrangement." Key Engineering Materials 409 (March 2009): 244–51. http://dx.doi.org/10.4028/www.scientific.net/kem.409.244.

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The paper presents the analysis of the fracture path in composites with the alumina or zirconia matrix containing inclusions of another oxide or tungsten carbide. The description concerns the fracture of composite systems with 10 vol.% of inclusions (particulate composites), other three-systems with 33 vol.% of inclusions of each phase and the two phase composite with the equal phase content (50 : 50 vol.%). The different phase proportion and diversified content of inclusions cause significant differences in the microstructure of composites. The main difference between particulate composites and composites with continuous phases depends on a possibility of occurrence of toughening mechanisms connected with crack – inclusions interactions. In connection with a different interphase boundary strength, this phenomenon leads to significant differences in the way of composite fracture. The presented results of mechanical properties of composites were analyzed in the aspect of their way of fracture.

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Matsuo, T. "Analysis on Thermoplastic Composites Systems." Advanced Composites Letters 1, no. 5 (September 1992): 096369359200100. http://dx.doi.org/10.1177/096369359200100504.

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Many kinds of molding materials and molding methods relating to thermoplastic composites have ever been developed. An attempt to make clear arrangement for these materials and molding methods was carried out. Materials were systematically classified. The relationships among materials, molding methods and molded parts were summarized in a table.

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Li, Yan, Han Zhang, Ton Peijs, and Emiliano Bilotti. "Graphene Delivery Systems for Hierarchical Fiber Reinforced Composites." MRS Advances 1, no. 19 (2016): 1339–44. http://dx.doi.org/10.1557/adv.2016.92.

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ABSTRACTThree different methods are evaluated for the introduction of graphene nanoplatelets (GNP) in hierarchical carbon- or glass fiber reinforced plastics. They involve; (1) direct infusion of GNP filled epoxy resin, (2) spray coating of GNP on fiber preforms and (3) the use of dissolvable thermoplastic interleaf carrier films. Direct infusion of GNP filled resin is the easiest method to deliver GNP into composite laminates but may lead to viscosity and filtration issues. Automated spray coating was set up to manufacture GNP modified carbon- or glass fiber fabrics, while graphene filled phenoxy interleaf films were manufactured by bar coating, both followed by resin infusion using neat epoxy resin to produce GNP modified epoxy laminates, without the disadvantages of GNP filled resins. No substantial difference in interlaminar shear strength (ILSS) for composites manufactured using the different delivery methods is found. However, the electrical conductivity of the GNP modified glass-fiber composites manufactured by spray coating of glass fabrics is two orders of magnitude higher than for laminates made by direct infusion of GNP modified resin.

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Xu, Ling, and Rui Yang. "Stearic Acid/Inorganic Porous Matrix Phase Change Composite for Hot Water Systems." Molecules 24, no. 8 (April 15, 2019): 1482. http://dx.doi.org/10.3390/molecules24081482.

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The storage and utilization of waste heat in low and medium temperature ranges using phase change materials (PCMs) is an effective technology to improve energy utilization efficiency in combined cooling, heating, and power (CCHP) systems. In this paper, stearic acid/inorganic porous matrix phase change composites were developed to store waste heat for hot water systems. Among them, stearic acid/expanded graphite (EG) phase change composite was highlighted and the thermal physical properties, the dynamic response, and the long-term cyclic stability were evaluated. The stearic acid concentrations in the composites were over 95 wt%. The thermal diffusion coefficients were 3–5 times higher than pure stearic acid, independent of composite densities. Accordingly, the heat storage and release times were decreased by up to 41% and 55%, respectively. After 100 cycles, the composites maintained good dynamic response and long-term cyclic stability, with heat storage density of 122–152 MJ/m3. Hence, this stearic acid/EG phase change composite exhibits excellent comprehensive performances. It is also easy to be prepared and flexible for various types of heat exchangers.

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Fodarella, Cristina, Heidi Kuivaniemi-Smith, Julie Gawrylowicz, and Charlie D. Frowd. "Forensic procedures for facial-composite construction." Journal of Forensic Practice 17, no. 4 (November 9, 2015): 259–70. http://dx.doi.org/10.1108/jfp-10-2014-0033.

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Purpose – The paper provides a detailed description of standard procedures for constructing facial composites. These procedures are relevant to forensic practice and are contained in the technical papers of this special issue; the purpose of this paper is also to provide an expanding reference of procedures for future research on facial composites and facial-composite systems. Design/methodology/approach – A detailed account is given of the interaction between practitioner and witness for producing a facial composite. This account involves an overview of the Cognitive Interview (CI) and the Holistic CI (H-CI) techniques used to obtain a description of the face of an offender (target); the authors then describe how this information is used to produce a composite from five popular face-production systems: Sketch, PRO-fit, Electronic Facial Identification Technique (E-FIT), EvoFIT and EFIT-V. An online annex is also made available to provide procedural information for additional composite systems. Practical implications – The work is valuable to forensic practitioners and researchers as a reference for interviewing techniques (involving a CI or an H-CI) and using facial-composite systems. Originality/value – The authors provide an accessible, current guide for how to administer interviewing techniques and how to construct composites from a range of face-production systems.

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Koh, Richard, Gisele Neiva, Joseph Dennison, and Peter Yaman. "Finishing Systems on the Final Surface Roughness of Composites." Journal of Contemporary Dental Practice 9, no. 2 (2008): 138–45. http://dx.doi.org/10.5005/jcdp-9-2-138.

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Abstract Aim This study evaluated differences in surface roughness of a microhybrid (Gradia™ Direct, GC America) and a nanofil (Filtek™ Supreme, 3M™ ESPE™) composite using four polishing systems: PoGo™/Enhance® (DENTSPLY/Caulk), Sof-Lex™ (3MTM ESPE™), Astropol® (Ivoclar Vivadent), and Optidisc™ (KerrHawe). Methods and Materials An aluminum mold was used to prepare 2 X 60 composite disks (10 mm X 2 mm). Composite was packed into the mold, placed between two glass slabs, and polymerized for 40 seconds from the top and bottom surfaces. Specimens were finished to a standard rough surface using Moore's disks with six brushing strokes. Specimens were rinsed and stored in artificial saliva in individual plastic bags at 36°C for 24 hours prior to testing. Specimens were randomly assigned to one of the four polishing systems and were polished for 30 seconds (10 seconds per grit) with brushing strokes according to the manufacturer's instructions. Mean surface roughness (Ra) was recorded with a surface-analyzer 24 hours after storage in artificial saliva, both before and after polishing. Means were analyzed using two-way and one-way analysis of variance (ANOVA) and Tukey multiple comparison tests at p < 0.05. Results There was a statistically significant difference for baseline measures between Filtek™ and Gradia™ (p=0.0338). For Filtek™, Sof-Lex™ provided a significantly smoother surface (Ra=0.80 ± 0.21) than Optidisc™ (Ra=0.93 ± 0.28), Astropol® (Ra=1.15 ± 0.24), and Pogo™/Enhance® (Ra=1.39 ± 0.39). For Gradia, Sof-Lex™ provided a significantly smoother surface (Ra=0.47 ± 0.09) and Astropol® provided a significantly rougher surface (Ra=1.39 ± 0.19) than Pogo™/Enhance® (Ra=1.11 ± 0.20) and Optidisc™ (Ra=1.15 ± 0.18). There was no significant difference in roughness between composites for individual polishing systems (p=0.3991). Conclusion Filtek™ specimens were smoother than Gradia™ specimens after baseline roughening. Sof- Lex™ provided the smoothest final surface when used with either composite. Astropol® provided a rough surface for Gradia™ specimens. Citation Koh R, Neiva G, Dennison J, Yaman P. Finishing Systems on the Final Surface Roughness of Composites. J Contemp Dent Pract 2008 February;(9)2:138-145.

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Gallyamov, A. R., I. D. Ibatullin, and A. Y. Murzin. "Improvement of Electrical Insulating and Anti-Wear Properties of Composites Used in Telemetry Systems." Applied Mechanics and Materials 792 (September 2015): 578–81. http://dx.doi.org/10.4028/www.scientific.net/amm.792.578.

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This article deals with the research results of electroinsulated and tribotechnical properties of composite materials on the basis of epoxide resin. The effect of fillers — micro-and nanopowders of various materials - on the properties of composites is examined. The use of composites in the manufacture of separators for telemetry systems is demonstrated.

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Bobek, Jiří, Petr Lenfeld, Jiří Habr, Martin Seidl, and Luboš Běhálek. "New Silane and MAPP Coupling Agents as Natural Composites Production Systems Improvement." Key Engineering Materials 669 (October 2015): 52–59. http://dx.doi.org/10.4028/www.scientific.net/kem.669.52.

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Still more and more applications using synthetic polymers find new material alternative in materials based on synthetic polymer filled with nature fibers mainly plant fibers. Not only in common applications but also in technical applications is possible to use nature fiber composites. But some additional modifications are necessary to perform to gain properties possible to use in technical applications. Mainly increasing adhesion between matrix and fibers is the most common intent of these additional operations. This paper deals with maleic anhydride based coupling agent and silane coupling agent effect in the polypropylene matrix and jute fiber composite and its mechanical properties. By using of silane coupling agents was achieved mechanical properties which are possible to compare with composites with glass fibers mechanical properties mainly in case of the flexural and tensile modulus and mainly was gained significant increasing of composite production system stability.

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Gudder, Stanley P. "Parts and Composites of Quantum Systems." Symmetry 13, no. 6 (June 8, 2021): 1031. http://dx.doi.org/10.3390/sym13061031.

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We consider three types of entities for quantum measurements. In order of generality, these types are observables, instruments and measurement models. If α and β are entities, we define what it means for α to be a part of β. This relationship is essentially equivalent to α being a function of β and in this case β can be employed to measure α. We then use the concept to define the coexistence of entities and study its properties. A crucial role is played by a map α^ which takes an entity of a certain type to one of a lower type. For example, if I is an instrument, then I^ is the unique observable measured by I. Composite systems are discussed next. These are constructed by taking the tensor product of the Hilbert spaces of the systems being combined. Composites of the three types of measurements and their parts are studied. Reductions in types to their local components are discussed. We also consider sequential products of measurements. Specific examples of Lüders, Kraus and trivial instruments are used to illustrate various concepts. We only consider finite-dimensional systems in this article. Finally, we mention the role of symmetry representations for groups using quantum channels.

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Breiman, Uri, Jacob Aboudi, and Rami Haj-Ali. "Semianalytical compressive strength criteria for unidirectional composites." Journal of Reinforced Plastics and Composites 37, no. 4 (November 19, 2017): 238–46. http://dx.doi.org/10.1177/0731684417740982.

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The compressive strength of unidirectional composites is strongly influenced by the elastic and strength properties of the fiber and matrix phases, as well as by the local geometrical properties, such as fiber volume fraction, misalignment, and waviness. In the present investigation, two microbuckling criteria are proposed and examined against a large volume of measured data of unidirectional composites taken from the literature. The first criterion is based on the compressive strength formulation using the buckling of Timoshenko’s beam. It contains a single parameter that can be determined according to the best fit to experimental data for various types of polymeric matrix composites. The second criterion is based on buckling-wave propagation analogy using the solution of an eigenvalue problem. Both criteria provide closed-form expressions for the compressive strength of unidirectional composites. We propose modifications of the two criteria by a fitting approach, for a wide range of fiber volume fractions, applied to four classes of unidirectional composite systems. Furthermore, a normalized form of the two models is presented after calibration in order to compare their prediction against experimental data for each of the material systems. The new modified criteria are shown to give a good match to a wide range of unidirectional composite systems. They can be employed as practical compression failure criteria in the analysis and design of laminated structures.

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Davis, J. B., D. B. Marshall, K. S. Oka, R. M. Housley, and P. E. D. Morgan. "Ceramic composites for thermal protection systems." Composites Part A: Applied Science and Manufacturing 30, no. 4 (April 1999): 483–88. http://dx.doi.org/10.1016/s1359-835x(98)00138-9.

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Dong, Xueguang, Hongguang Zhang, Yongtao Li, Hao Liu, Kai Chen, Qingteng Hou, Yongchao Huang, and Qi Li. "Lattice mismatching effect in composites systems." Journal of Physics: Conference Series 430 (April 22, 2013): 012073. http://dx.doi.org/10.1088/1742-6596/430/1/012073.

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Eckert, Jürgen, Guo He, Jayanta Das, and Wolfgang Löser. "Nanostructured Composites in Multicomponent Alloy Systems." MATERIALS TRANSACTIONS 44, no. 10 (2003): 1999–2006. http://dx.doi.org/10.2320/matertrans.44.1999.

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Welder, S. M., H. J. Lause, and R. Fountain. "Structural repair systems for thermoplastic composites." Materials & Design 7, no. 3 (May 1986): 147–49. http://dx.doi.org/10.1016/0261-3069(86)90007-5.

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Dyana Merline, J., and C. P. Reghunadhan Nair. "Carbon / Epoxy Resin Based Elastic Memory Composites." Eurasian Chemico-Technological Journal 14, no. 3 (May 23, 2012): 227. http://dx.doi.org/10.18321/ectj118.

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Elastic memory composites were processed from shape memory epoxy resins and carbon fabric reinforcements. Three different types of epoxies (diglycidyl ether of bisphenol-A, tris(4-glycidyloxy phenyl)methane, and epoxy novolac) were used as matrices. Developed composites were evaluated for flexural strength and analyzed by Dynamic Mechanical Thermal analysis. Of the three different epoxy systems with carbon: resin ratio of 50:50, the composite with diepoxy system exhibited maximum glass transition value of 119 °C, epoxy novalac system exhibited a low glass transition value of 54 °C and the tris epoxy system exhibited a glass transition of 100 °C respectively. The flexural strength and modulus of the composites were optimised at a concentration of 40 wt.%. The transition temperature also showed a maximum at around this composition. Bending test was adopted for the shape memory evaluation. All the developed composites exhibited more than 90% shape recovery. The diepoxy resin series of composites exhibited the maximum shape recovery of 97%. The shape recovery properties of the tris epoxy and epoxy novolac-based composites were inferior. For the diepoxy resin-based system, the shape recovery time was proportional to the resin content. The shape recovery of composite with 80% resin was demonstrated experimentally. The properties of the composites show that these systems have the required elastic memory characteristics for possible use in thermo-responsive self-deployable applications.

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Barcellos, Daphne Camara, Alexandre Luiz Souto Borges, Alessandra Buhler Borges, Patricia Rondon Pleffken, and Sigmar Mello Rode. "Surface roughness of indirect composites using different polishing systems." Brazilian Dental Science 16, no. 4 (December 10, 2013): 77. http://dx.doi.org/10.14295/bds.2013.v16i4.927.

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Objective: The aim of this study was to evaluatethe surface roughness of indirect composites afterpolishing with aluminum oxide (Al2O3) discs. Materialand Methods: One-hundred and eighty specimenswere confectioned with 6 indirect composites using aprefabricated matrix, resulting in six groups (n-30):Group SO - Solidex, Group SI - Signum, Group SF- Sinfony, Group OP - Opallis; Group RE - Resilab,Group EP - Epricord, Group AD - Adoro. Each groupwas divided into three subgroups according to thepolishing (n-10): Subgroup C (Control) - withoutpolishing (polyester strip); Subgroup S - polishingwith Sof-Lex discs; Subgroup T - polishing with TDVdiscs. The surface roughness was measured with aprofilometer. Results: The results were analyzed byANOVA and Tukey tests (5%), resulting in p = 0.00.The mean values (±standard-deviation) measured inRa (μm) for each Group/Subgroup were: RE/C - 0.14(± 0.14) a; EP/C - 0.18 (± 0.46) ab; SO/C - 0.24 (±0.22) abc; SF/S - 0.24 (± 0.17) abc; SF/C - 0.26 (±2.54)abc; SI/C - 0.30 (± 0.34)abcd; SO/T - 0.33(±0.42) abcd; AD/S - 0.34(± 0.88)abcd; AD/C - 0.37(±0.60)ab; SI/S - 0.37(± 1.39)bcd; SO/S - 0.43(± 0.26)cd; EP/S – 0.44 (± 1.02) cd; RE/S - 0.54(±2.02) de;SI/T - 0.65(± 0.88)ef; RE/T - 0.83 (± 0.54) fg; SF/T- 0.85 (± 0.21) fg; AD/T - 0.88 (± 1.74) fg; EP/T- 0.91(± 0.89) g. Conclusion: It is concluded thatpolyester strip resulted in significantly lowest surfaceroughness; polishing with TDV discs resulted insignificantly higher surface roughness compared toSof-Lex discs and that the surface roughness resultsdepend on the composite tested.Keywords Composite resins; Dental polishing; Biofilms.

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Ambrosano, Gláucia Maria Bovi, Larissa Maria Assad Cavalcante, Alessandra Resende Peris, André Vicente Ritter, and Luiz André Freire Pimenta. "Effect of Photoactivation Systems and Resin Composites on the Microleakage of Esthetic Restorations." Journal of Contemporary Dental Practice 8, no. 2 (2007): 70–79. http://dx.doi.org/10.5005/jcdp-8-2-70.

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Abstract Aim The aim of this study was to evaluate the influence of four photoactivation systems [quartz tungsten halogen (QTH), light-emitting diode (LED), argon ion laser (AL), and plasma arc curing PAC)] on cementum/ dentin and enamel microleakage of Class II restorations using a microhybrid [Z250 – 3M ESPE] and two packable composites [(SureFil - Dentsply and Tetric Ceram HB – Ivoclair/Vivadent]. Methods and Materials Three hundred sixty “vertical-slot Class II cavities” were prepared at the mesial surface of bovine incisors using a 245 carbide bur in a highspeed handpiece. Specimens were divided into twelve groups (composite-photoactivation systems). Half of the specimens had the gingival margin placed in enamel (n=15) and the other half in cementum/dentin (n=15). Composites were inserted and cured in 2 mm increments according to manufacturers’ recommended exposure times. After polishing, the samples were immersed in 2% methylene blue solution, sectioned, and evaluated at the gingival margins. Data were submitted to statistical analysis using the Kruskal–Wallis and Mann-Whitney tests. Results No significant differences were found among the photoactivation systems and among resin composites (p>0.05). Microleakage was not significantly affected by location (enamel vs. cementum/dentin, p>0.05). These findings suggested neither the photoactivation systems nor the resin composite types might have an effect on the microleakage at gingival margins Class II cavities. Citation Cavalcante LMA, Peris AR, Ambrosano GMB, Ritter AV, Pimenta LAF. Effect of Photoactivation Systems and Resin Composites on the Microleakage of Esthetic Restorations. J Contemp Dent Pract 2007 February;(8)2:070-079.

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Rajaram, G., S. Kumaran, and T. Srinivas Rao. "Tensile Behaviour of Al-Si Alloy and Al-Si/Graphite Composites at Elevated Temperatures." Materials Science Forum 710 (January 2012): 457–62. http://dx.doi.org/10.4028/www.scientific.net/msf.710.457.

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The high temperature tensile behaviour of Al-Si alloy and two of its composite systems with graphite as major reinforcement were investigated. The composites were developed by the stir casting method, wherein a mixture of graphite (3 wt %) and Cu / Ni (2 wt% each) were added into the molten Al-Si alloy to fabricate two systems such as Al-Si-Cu/graphite composite and Al-Si-Ni/graphite composite. The properties of composites were better than that of the matrix alloy. Tensile behaviour of alloy and composites were studied at different temperatures from room temperature to 300°C. It is found that the tensile strength of the alloy and composites were decreasing with increase in temperature. The transition elements (Cu / Ni) have played the key role in improving the ultimate tensile and yield strength of the composites over the alloy. The flow stress of the composite is more than that of the alloy. The strain hardening exponent value continuously drops with the increase of tensile temperature due to the thermal softening effect. The % elongation of the alloy is more than that of the composites. Fracture surfaces of the samples are analyzed by scanning electron microscope to understand the fracture mechanisms. Fractography reveals that the fracture behaviour of the alloy changes from cleavage mode at room temperature to complete ductile mode at high temperature.

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Pekmezci, Bekir Y., Egemen Arabaci, and Cenk Ustundag. "Freeze-Thaw Durability of Lime Based FRCM Systems for Strengthening Historical Masonry." Key Engineering Materials 817 (August 2019): 174–81. http://dx.doi.org/10.4028/www.scientific.net/kem.817.174.

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In recent years, FRCM systems have become a preferred strengthening system in reinforced concrete structures together with masonry structures. The most important factor in the choice of FRCM as a strengthening system is its compatibility with concrete or masonry substrates. In addition, high fire resistance is an important factor in their preference. The components of FRCM composites are known to have high durability separately. However, the durability of composites, composed of a combination of fabric and matrices is still a matter of no detailed reported knowledge. In this experimental study, the durability properties of FRCM composites with lime matrix reinforced with glass and glass-polypropylene hybrid fabrics were investigated. Composite samples were subjected to tensile and bending tests before and after freeze thaw cycles. Load-deformation relations were obtained. As a result of the experimental study, the following results can be drawn: Following freeze thaw cycles, reduction in the bending and tensile performances of the biaxial glass fabric reinforced composite samples as well as matrix samples were obtained. A significant decrease of deformation capability was determined for biaxial glass fabric reinforced matrices and plain matrix.

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Gordon-Nuñez, Franklin, Katherine Vaca-Escobar, Milton Villacís-García, Lenys Fernández, Alexis Debut, María Belén Aldás-Sandoval, and Patricio J. Espinoza-Montero. "Applicability of Goethite/Reduced Graphene Oxide Nanocomposites to Remove Lead from Wastewater." Nanomaterials 9, no. 11 (November 7, 2019): 1580. http://dx.doi.org/10.3390/nano9111580.

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Lead ion in drinking water is one of the most dangerous metals. It affects several systems, such as the nervous, gastrointestinal, reproductive, renal, and cardiovascular systems. Adsorption process is used as a technology that can solve this problem through suitable composites. The adsorption of lead (Pb(II)) on graphene oxide (GO) and on two goethite (α-FeOOH)/reduced graphene oxide (rGO) composites (composite 1: 0.10 g GO: 22.22 g α-FeOOH and composite 2: 0.10 g GO: 5.56 g α-FeOOH), in aqueous medium, was studied. The GO was synthesized from a commercial pencil lead. Composites 1 and 2 were prepared from GO and ferrous sulfate. The GO and both composites were characterized by using scanning electron microscopy (SEM), scanning transmission electron microscopy (STEM), Raman spectroscopy, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and dynamic light scattering (DLS). The adsorption capacity of Pb(II) on the GO and both composites was evaluated through adsorption isotherms. Composite 1 presented a significant agglomeration of α-FeOOH nanorods on the reduced graphene oxide layers. Meanwhile, composite 2 exhibited a more uniform distribution of nanorods. The adsorption of Pb(II) on the three adsorbents fits the Langmuir isotherm, with an adsorption capacity of 277.78 mg/g for composite 2200 mg/g for GO and 138.89 mg/g for composite 1. Composite 2 emerged as a highly efficient alternative to purify water contaminated with Pb(II).

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Courtright, E. L. "A comparison of MoSi2 matrix composites with other silicon-base composite systems." Materials Science and Engineering: A 261, no. 1-2 (March 1999): 53–63. http://dx.doi.org/10.1016/s0921-5093(98)01049-1.

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Deleanu, Lorena, and Constantin Georgescu. "Water lubrication of PTFE composites." Industrial Lubrication and Tribology 67, no. 1 (February 9, 2015): 1–8. http://dx.doi.org/10.1108/ilt-11-2011-0095.

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Purpose – The paper aims to present results on the friction and the wear of polytetrafluoroethylene (PTFE) and eight commercially available composites with PTFE matrix, for tests done on shoe/roller tribotester with water lubrication in open circuit. There are pointed out particular tribological processes within the superficial layers of the composites with the help of optical microscopy. Design/methodology/approach – Analysing the tribological behaviour of eight grades of PTFE composites sliding in water on shoe/roller tribotester. Findings – Good results of wear behaviour under water lubrication for all the composites. PTFE exhibits severe wear under the tested regime. Originality/value – The research could support PTFE composite application for water lubricated systems.

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Garkina, Irina, and Alexander Danilov. "Kinetic Processes in Polydisperse Systems: Experience of Practical Approximation." Key Engineering Materials 814 (July 2019): 33–37. http://dx.doi.org/10.4028/www.scientific.net/kem.814.33.

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Composite material is considered as a complex system with corresponding system attributes. The systematization of studies on the structure formation of composites is carried out to ensure the fundamentalization of building materials based on the use of analytical methods. The experience of using the linearization of kinetic processes in polydisperse systems is given. The most important cases are considered. Examples of parametric identification of a table-specified and nonlinear kinetic processes are given. The results were used in the development of special purpose composite materials.

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Chiu, Hsing-Pang, S. M. Jeng, and J.-M. Yang. "Interface control and design for SiC fiber-reinforced titanium aluminide composites." Journal of Materials Research 8, no. 8 (August 1993): 2040–53. http://dx.doi.org/10.1557/jmr.1993.2040.

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The effectiveness of several coating systems which were used as a diffusion barrier for the SiC fiber-reinforced titanium aluminide composites was investigated. TaC, TiC, TiB2, B, C/graded TiB2, and Ag/Ta were applied to the SiC fiber via chemical vapor deposition and physical vapor deposition. The interfacial compatibility, interfacial stability, thermal residual stress, interfacial bond strength, and the transverse fracture behavior of the composites with coated fibers were characterized and determined. The results show that none of the above coating systems can satisfy the requirements for a strong, tough, and damage-tolerant SiC fiber-reinforced titanium aluminide composite. Several multilayer, multifunctional coating systems are proposed.

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Dangelmaier, Wilhelm, Thomas Sommer-Dittrich, Jenny Streichhan, and Markus Monhof. "Information Systems for Composite Materials: Requirements and Challenges." Applied Mechanics and Materials 597 (July 2014): 59–62. http://dx.doi.org/10.4028/www.scientific.net/amm.597.59.

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Using fiber-reinforced composites (FRC) in automotive lightweight construction currently is too expensive to achieve a wide distribution. To assist the engineers’ material selection process suitable information systems are needed. Development of those are a hard task due to the complex structure of FRC. In this paper we give an insight to the problem domain and introduce requirements which should be met by an information system for composite data storage.

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Rhodes, Gillian, Kieran Lee, Romina Palermo, Mahi Weiss, Sakiko Yoshikawa, Peter Clissa, Tamsyn Williams, Marianne Peters, Chris Winkler, and Linda Jeffery. "Attractiveness of Own-Race, Other-Race, and Mixed-Race Faces." Perception 34, no. 3 (March 2005): 319–40. http://dx.doi.org/10.1068/p5191.

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Averaged face composites, which represent the central tendency of a familiar population of faces, are attractive. If this prototypicality contributes to their appeal, then averaged composites should be more attractive when their component faces come from a familiar, own-race population than when they come from a less familiar, other-race population. We compared the attractiveness of own-race composites, other-race composites, and mixed-race composites (where the component faces were from both races). In experiment 1, Caucasian participants rated own-race composites as more attractive than other-race composites, but only for male faces. However, mixed-race (Caucasian/Japanese) composites were significantly more attractive than own-race composites, particularly for the opposite sex. In experiment 2, Caucasian and Japanese participants living in Australia and Japan, respectively, selected the most attractive face from a continuum with exaggerated Caucasian characteristics at one end and exaggerated Japanese characteristics at the other, with intervening images including a Caucasian averaged composite, a mixed-race averaged composite, and a Japanese averaged composite. The most attractive face was, again, a mixed-race composite, for both Caucasian and Japanese participants. In experiment 3, Caucasian participants rated individual Eurasian faces as significantly more attractive than either Caucasian or Asian faces. Similar results were obtained with composites. Eurasian faces and composites were also rated as healthier than Caucasian or Asian faces and composites, respectively. These results suggest that signs of health may be more important than prototypicality in making average faces attractive.

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Aljamhan, Abdullah, Syed Rashid Habib, Mohammed A. AlSarhan, Bashayer AlZahrani, Hessa AlOtaibi, and Norah AlSunaidi. "Effect of Finishing and Polishing on The Surface Roughness of Bulk Fill Composites." Open Dentistry Journal 15, no. 1 (February 16, 2021): 25–32. http://dx.doi.org/10.2174/1874210602115010025.

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Objective: The aim of this in vitro study was to compare the effect of three finishing/polishing systems on the surface roughness (Ra) of conventional and Bulk-fill composite resins. Materials and methods: The Ra values of three different brands of Bulk-fill composites (Filtek Bulk-fill®, 3M ESPE; SonicFill Bulk-fill®, Kerr; SDR Bulk-fill®, Dentsply) were tested and compared with the Ra of a conventional composite (Filtek XT Z350®, 3M ESPE). A total of 30 discs (10 mm × 2 mm) were fabricated from four test materials and divided into three groups (n = 10/group) depending on the three finishing/polishing systems used (Astropol®, Ivoclar Vivadent; PoGo®, Dentsply; Sof-LexTM®, 3M ESPE). The Ra of each specimen was recorded with an optical profilometer (Contour-GT-X®, USA). ANOVA and Tukey’s tests were used for statistical analysis. Results: Statistically significant differences (P < 0.05) were observed between the Ra values of all composite materials tested with three finishing/polishing systems. Among composite materials, only Group-III showed a significant difference (P = 0.003) in Ra obtained using all three finishing/polishing systems. SDR Bulk-fill® and Filtek XT Z350® showed the highest (0.810 ± 0.373 µm) and lowest (0.365 ± 0.119 µm) Ra values, respectively. Individually, the highest Ra was recorded for SDR Bulk-fill® when it was finished/polished with the Astropol® system. SonicFill Bulk-fill® and SDR Bulk-fill® composites exhibited the lowest Ra values when they were finished with the PoGo® system. Conclusion: Finishing and polishing techniques greatly affect the surface roughness of different Bulk-fill composites because variations in the surface roughness were observed for all tested composite materials. Filtek XT Z350® exhibited the lowest surface roughness, while SDR Bulk-fill® exhibited the highest surface roughness among the tested composite materials.

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Giacomelli, Luca, Giacomo Derchi, Andrea Frustaci, Orlando Bruno, Ugo Covani, Antonio Barone, Daniele De Santis, and Francesco Chiappelli. "Surface Roughness of Commercial Composites after Different Polishing Protocols: An Analysis with Atomic Force Microscopy." Open Dentistry Journal 4, no. 1 (September 15, 2010): 191–94. http://dx.doi.org/10.2174/1874210601004010191.

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Background and Aims: Polishing may increase the surface roughness of composites, with a possible effect on bacterial growth and material properties. This preliminary in vitro study evaluates the effect of three different polishing systems (PoGo polishers, Enhance, Venus Supra) on six direct resin composites (Gradia Direct, Venus, Venus Diamond, Enamel Plus HFO, Tetric Evoceram, Filtek Supreme XT). Materials and Methods: For each composite, 12 square specimens were prepared: 9 specimens were polished, three for each different method, while three specimens were used as controls. Surface roughness was determined with AFM by measuring Root Mean Square (RMS) of average height. Results: PoGo polisher determined a significantly rougher surface, versus controls, in 5 out of 6 composites evaluated. Some significant differences from unpolished controls were observed also for Enhance polishing. Polishing with Venus Supra did not result in any significant difference in surface roughness versus controls. No differences were observed between different polishing systems. Conclusions: These preliminary results suggest that Venus Supra polishing system could determine a smoother composite surface if compared to the other polishing systems tested. On this basis, we are conducting an in vivo study to evaluate bacterial colonization on some combinations of composites and polishing protocols.

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Park, Chong Sung, Hyun Seok Hong, Myung Ho Kim, and Chong Mu Lee. "Thermal Expansion Behavior of the Multiphase Composite System." Materials Science Forum 449-452 (March 2004): 765–68. http://dx.doi.org/10.4028/www.scientific.net/msf.449-452.765.

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A new approach for the CTE on the basis of Ashelby.s cutting and welding process was made for the analysis of the thermal expansion behaviors of Al-Si alloys and composites. In this theoretical approach, it was considered that relaxation of residual stress could create an elastoplastic zone in the matrix around a particle during cooling. A comparison of the measured CTEs with the calculated ones for the Al-Si-SiCp and Al-Si-Al2O3 composite systems was performed in terms of the volume percent and the size of reinforced phases. The calculated results revealed that the linear CTE of the both composite depends on the size of the reinforce phases, especially at the composite systems with a low volume percent of the reinforce phases. The increase in the volume percentages of Al2O3, SiCp and Si phase lowers the linear CTEs of the systems. The measured CTEs was deviated less than about ten percents from the calculated ones at composites with a high volume percent. The deviations of the CTEs of reinforced phases are about 4 - 6 vol% from real composite systems.

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Feltman, R. S., and M. H. Santare. "Anisotropic Effective Moduli of Cracked Short-Fiber Reinforced Composites." Journal of Applied Mechanics 66, no. 3 (September 1, 1999): 709–13. http://dx.doi.org/10.1115/1.2791629.

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A model is presented to analyze the effect of fiber fracture on the anisotropic elastic properties of short-fiber reinforced composite materials. The effective moduli of the material are modeled using a self-consistent scheme which includes the calculated energy dissipated through the opening of a crack in an arbitrarily oriented elliptical inclusion. The model is an extension of previous works which have modeled isotropic properties of short-fiber reinforced composites with fiber breakage and anisotropic properties of monolithic materials with microcracks. Two-dimensional planar composite systems are considered. The model allows for the calculation of moduli under varying degrees of fiber alignment and damage orientation. In the results, both aligned fiber systems and randomly oriented fiber systems with damage-induced anisotropy are examined.

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Valášek, P., and M. Brožek. "Degradation of polymer particle systems in agrocomplex." Research in Agricultural Engineering 59, No. 2 (May 31, 2013): 46–50. http://dx.doi.org/10.17221/12/2012-rae.

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One of the possibilities of recycling waste from blasting processes is the application of these secondary materials in polymeric matrix, where the primary material is replaced with the secondary one. By this quite specific recycling process a new material arises – polymeric particle composite. It is a case of two phase system, properties of which are defined by the mutual interaction of single components. One of the possible applications of these systems is agrocomplex. Systems used in agrocomplex environment can be subjected to specific influences, which change their mechanical properties in some time – degradation occurs. This contribution occupies with degradation processes of polymeric particle composites on the basis of waste-corundum after exposure to chosen degradation media, which are typical for agrocomplex environment. Changes of hardness, abrasive wear resistance and tensile strength in dependence on exposure time were tested.  

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Frowd, Charlie D., William B. Erickson, James M. Lampinen, Faye C. Skelton, Alex H. McIntyre, and Peter J. B. Hancock. "A decade of evolving composites: regression- and meta-analysis." Journal of Forensic Practice 17, no. 4 (November 9, 2015): 319–34. http://dx.doi.org/10.1108/jfp-08-2014-0025.

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Purpose – The purpose of this paper is to assess the impact of seven variables that emerge from forensic research on facial-composite construction and naming using contemporary police systems: EvoFIT, Feature and Sketch. Design/methodology/approach – The paper involves regression- and meta-analyses on composite-naming data from 23 studies that have followed procedures used by police practitioners for forensic face construction. The corpus for analyses contains 6,464 individual naming responses from 1,069 participants in 41 experimental conditions. Findings – The analyses reveal that composites constructed from the holistic EvoFIT system were over four-times more identifiable than composites from “Feature” (E-FIT and PRO-fit) and Sketch systems; Sketch was somewhat more effective than Feature systems. EvoFIT was more effective when internal features were created before rather than after selecting hair and the other (blurred) external features. Adding questions about the global appearance of the face (as part of the holistic-cognitive interview (H-CI)) gives a valuable improvement in naming over the standard face-recall cognitive interview (CI) for all three system types tested. The analysis also confirmed that composites were considerably less effective when constructed from a long (one to two days) compared with a short (0-3.5 hours) retention interval. Practical implications – Variables were assessed that are of importance to forensic practitioners who construct composites with witnesses and victims of crime. Originality/value – Using a large corpus of forensically-relevant data, the main result is that EvoFIT using the internal-features method of construction is superior; an H-CI administered prior to face construction is also advantageous (cf. face-recall CI) for EvoFIT as well as for two further contrasting production systems.

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Sunsaneeyametha, Weeraw, Angkhana Jaroenworaluck, Nudthakarn Kosachan, and Ron Stevens. "Relation between Degree of Conversion and Post-Cured Properties of Light Cured Composite Systems Used as Filling Materials." Key Engineering Materials 334-335 (March 2007): 401–4. http://dx.doi.org/10.4028/www.scientific.net/kem.334-335.401.

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The composite, based on a polymer matrix such as Bisphenol A glycol dimethacrylate (Bis-GMA), urethane dimethacrylate (UDMA), and triethyleneglycoldimethacrylate (TEGDMA) and a reinforced-ceramic filler has been used in dental restorative materials. The light curing composite consists of Bis-GMA, TEGDMA, UDMA, Bis-GMA/TEGDMA, Bis-GMA/UDMA, or UDMA/TEGDMA polymer systems and a fumed silica filler with 35 weight ratio loading was synthesized using camphorquinone (CQ) and 2-(dimet6hyloamino)ethyl methacrylate (DMAEMA) as an initiator system. FTIR spectroscopy was used to determine the degree of conversion (DC) of the composites. Polymerization shrinkage and physical properties such as hardness strength and flexural strength were correlated with the composites containing different polymer systems.

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Badawy, AA, and EU Khashaba. "Impact and mechanical properties of different composite systems modified with multi-walled carbon nanotubes." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 234, no. 20 (April 15, 2020): 4087–100. http://dx.doi.org/10.1177/0954406220919445.

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Kevlar and glass fiber composites have distinguished mechanical properties such as specific strength and stiffness, resistance to impact loading, and tailoring the overall properties to meet the needs of a specific application. Enhancing their mechanical properties via incorporation of carbon nanotubes (CNTs) into their polymer matrices and proper characterization are very important for automotive and aerospace applications, which is the main objective of this study. This article presents an experimental study on manufacturing and mechanical characterization of six different materials. The tested materials include: CNT-nanocomposites, Kevlar fiber reinforce epoxy (KFRE) and glass fiber reinforced epoxy (GFRE) composites modified with CNTs. The CNTs were ultrasonically dispersed into the epoxy resin at 30% sonication amplitude (225 W) for 30 min to avoid their damage. The results were compared with the control materials (without CNTs). The mechanical tests are drop weight impact, tension, and in-plane shear. All the tests were performed according to ASTMs using computerized testing machines at room temperature. Results from the experimental study showed that the incorporation of the CNTs into the epoxy resin improves their tensile and shear strengths by 11% and 22.2%, respectively. In addition, the tensile and shear moduli of the CNT-nanocomposite were improved respectively by 68.7% and 29%. The absorbed energy and maximum contact force of the CNT-nanocomposite were improved by 11.4% and 9.5%, respectively. The tensile strength of the GFRE/CNT and KFRE/CNT composites showed improvements of 15.3% and 19.6%, respectively. The improvements in the tensile and shear moduli of GFRE/CNT and KFRE/CNT composites are in the range of 15–20%. The CNTs have marginal effects on the impact properties of the modified composite laminates. The tensile properties of the Kevlar composite systems (with and without CNTs) are higher than those of the glass composite systems and vice versa for the shear moduli and the absorbed energies.

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Berger, Stefan, Jürgen Weisser, Eberhard Müller, and Matthias Schnabelrauch. "In Situ Hardening Biodegradable and Malleable Polymer-Nanoapatite Composites." Materials Science Forum 638-642 (January 2010): 693–99. http://dx.doi.org/10.4028/www.scientific.net/msf.638-642.693.

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Composite systems composed of nanocrystalline apatites and oligolactide-based polymer networks were prepared resulting in malleable and even injectable formulations which can be cured to compact materials at body temperature. Porous devices with inter-connective porosity were obtained after addition of suitable foaming agents to the composite mixtures. Setting time, porosity and mechanical properties of the composites can be properly adjusted by varying the educt composition. The determined compressive strengths and Young’s moduli of the porous composites perfectly match the mechanical characteristics of cancellous bone material. Preliminary in vitro cell culture experiments with compact composite materials demonstrated their good cytocompatibility. Based on these findings, the synthesized nano-structured composites represent promising candidates for the development of new biomaterials usable in hard tissue regeneration.

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Benveniste, Y. "Exact Results Concerning the Local Fields and Effective Properties in Piezoelectric Composites." Journal of Engineering Materials and Technology 116, no. 3 (July 1, 1994): 260–67. http://dx.doi.org/10.1115/1.2904284.

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This paper consists of two parts: (a) a concise summary and discussion is given of the recent contributions of the author in the micromechanics of piezoelectric composites. The underlying theme here is the derivation of exact connections for the local fields and effective moduli of heterogeneous piezoelectric solids. Composites of arbitrary phase geometry as well as fibrous systems are considered. (b) New results are presented on the effective behavior of fibrous piezoelectric systems. Fibrous composites with transversely isotropic constituents and cylindrical microgeometry are considered. The exact connections of the author (Benveniste (1993), Proc. R. Soc., Series A, Vol. 441, pp. 59-81) are extended to include the most generally possible overall symmetry of the composite aggregate. The other category of the new findings concerns exact expressions for the effective thermal terms of fibrous systems which possess the same shear modulus GT.

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Parks, W. P., R. R. Ramey, D. C. Rawlins, J. R. Price, and M. Van Roode. "Potential Applications of Structural Ceramic Composites in Gas Turbines." Journal of Engineering for Gas Turbines and Power 113, no. 4 (October 1, 1991): 628–34. http://dx.doi.org/10.1115/1.2906287.

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A Babcock and Wilcox-Solar Turbines Team has completed a program to assess the potential for structural ceramic composites in turbines for direct coal-fired or coal gasification environments. A review is made of the existing processes in direct coal firing, pressurized fluid bed combustors, and coal gasification combined cycle systems. Material requirements in these areas were also discussed. The program examined state-of-the-art ceramic composite materials. Utilization of ceramic composites in the turbine rotor blades and nozzle vanes would provide the most benefit. A research program designed to introduce ceramic composite components to these turbines was recommended.

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Daud, Norlinda, and Robert A. Shanks. "Highly-filled hybrid composites prepared using centrifugal deposition." Journal of Polymer Engineering 34, no. 9 (December 1, 2014): 875–81. http://dx.doi.org/10.1515/polyeng-2013-0160.

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Abstract Natural composites of high filler content, such as nacre, a composite comprised of 95–99% w/w aragonite layers, have been of interest due to their hardness, strength and toughness. High filler content composites have been prepared synthetically, although due to viscosity and processing requirements, the filler content was limited compared with natural systems. In this paper we describe hybrid high filler content composites prepared to be biomimetic of nacre. Development of processing conditions increased the filler content from 50% w/w using a laboratory stirrer to obtain hybrid composites with 77–86% w/w filler content, prepared by centrifugal deposition and hot compression molding techniques. Both methods were very different from natural formation from layer-by-layer (LBL) construction, however, the composites formed were of high filler content approaching the level in nature. The composites exhibited high modulus and strength, although deformation at break was low, consistent with highly filled materials. Glass transition of the resin phase was increased slightly, while damping was decreased by filler content. Surface morphology of the fractured composite showed a layered structure of well dispersed fillers with minute voids scattered evenly, indicating that the composite was effectively compacted.

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Xu, Xingchi, and Tingwei Wang. "Electrical and rheological properties of carbon black and carbon fiber filled low-density polyethylene/ethylene vinyl acetate composites." Science and Engineering of Composite Materials 25, no. 4 (July 26, 2018): 715–23. http://dx.doi.org/10.1515/secm-2016-0080.

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Abstract In this study conductive composites of low-density polyethylene (LDPE)/ethylene-vinyl acetate (EVA) filled with carbon black (CB) and carbon fiber (CF) were prepared by melt-mixing method. The morphological, rheological, and electrical properties of CB filled composites were compared with CF filled composites by digital multimeter, scanning electron microscope, rotational rheometer, etc. The composites filled with different fillers have same percolation threshold but the EVA concentration has different effect on the two systems. For CB filled composites the increase in EVA concentration decreased resistivity first and reached lowest point when the LDPE:EVA ratio was 70:30; then the resistivity increased, but for CF filled composites the resistivity continued to decrease. The differences were caused by the diverse morphological and filler distribution of two different composite systems. The rheological behaviors of two types of composites also had significant difference; the value of complex viscosity of CB filled composites was about two orders of magnitude more than CF filled composites in low frequency region. It was because CB particles was nano-scale and had large surface area, so it had great influence on the value of complex viscosity of composites.

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Kopytkov, V. V. "Polymer gels for the protection of coniferous root systems from desiccation." Doklady of the National Academy of Sciences of Belarus 64, no. 3 (July 9, 2020): 379–84. http://dx.doi.org/10.29235/1561-8323-2020-64-3-379-384.

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The results of the development of composite polymer materials for processing root systems of seedlings in order to increase the survival rate of forest crops are presented. It has been established that the type of target additives and the concentration of water-soluble polymers in the compositions for processing can significantly affect the physicochemical properties of the composites and moisture loss by root systems of seedlings. The optimal compositions of composite polymer materials for protecting the root systems of a number of conifers from drying out are given.

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Steiner, Rene, Daniel Edelhoff, Bogna Stawarczyk, Herbert Dumfahrt, and Isabel Lente. "Effect of Dentin Bonding Agents, Various Resin Composites and Curing Modes on Bond Strength to Human Dentin." Materials 12, no. 20 (October 17, 2019): 3395. http://dx.doi.org/10.3390/ma12203395.

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This study investigated the influence of several dentin bonding agents, resin composites and curing modes on push-out bond strength to human dentin. 360 extracted caries-free third molars were prepared, cut into slices, embedded in epoxy resin and perforated centrally. One half of the specimens (180) were treated by using one-step adhesive systems and the other half (180) with multi-step adhesive systems. Subsequently, the cavities were filled with either universal, flowable or bulk-fill resin composite according to the manufactures’ product line and cured with either turbo or soft start program. After storage the push-out test was performed. The data was analyzed using Kolmogorov-Smirnov, three- and one-way ANOVA followed by the Scheffé post-hoc test, unpaired two-sample t-test (p < 0.05). The strongest influence on push-out bond strength was exerted by the resin composite type (partial eta squared ηP2 = 0.505, p < 0.001), followed by the adhesive system (ηP2 = 0.138, p < 0.001), while the choice of the curing intensity was not significant (p = 0.465). The effect of the binary or ternary combinations of the three parameters was significant for the combinations resin composite type coupled adhesive system (ηP2 = 0.054, p < 0.001), only. The flowable resin composites showed predominantly mixed, while the universal and bulk-fill resin composite showed adhesive failure types. Cohesive failure types were not observed in any group. Multi-step adhesive systems are preferable to one-step adhesive systems due to their higher bond strength to dentin. Flowable resin composites showed the highest bond strength and should become more important as restoration material especially in cavity lining. The use of a soft start modus for polymerization of resin composites does not enhance the bond strength to dentin.

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Mitoseriu, Liliana. "Fenómenos magnetoeléctricos en sistemas monobásicos y composites." Boletín de la Sociedad Española de Cerámica y Vidrio 44, no. 3 (June 30, 2005): 177–84. http://dx.doi.org/10.3989/cyv.2005.v44.i3.386.

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Valášek, Petr. "Tensile Strength of Sisal/Epoxy Composites Prepared by Vacuum Infusion." Materials Science Forum 911 (January 2018): 95–99. http://dx.doi.org/10.4028/www.scientific.net/msf.911.95.

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Composite systems are materials that due to its characteristics and its achievement of synergistic effects are increasingly applied. The most frequent composites are composites mainly with long fibers. In the interaction with the polymer matrix can be used inorganic fibers, but recently there is a substitution of these fibers with organic fibers. The main advantage of using organic fibers is their low cost, low weight, and availability. The benefits can also cite environmental aspects. The disadvantage is the very nature of the organic material. The paper describes a long-fiber composite system prepared by vacuum infusion and compares the tensile strength of composites with randomly oriented and arranged sisal fibers, depending on the flow direction of the resin during vacuum infusion. Composite systems were cut from boards made by vacuum infusion using a water jet. These boards are widely used by industries such as automotive or building to where the natural fibers can create design function. The use of natural fibers in this process is inexpensive and such materials can be referenced as biocomposites, saving the primary raw material. The paper describes the tensile strength and hardness. Electron microscopy was used to evaluate fracture surfaces and the morphology of the fibers.

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Akhundov, V. M. "Analysis of elastomeric composites based on fiber-reinforced systems. 2. Unidirectional composites." Mechanics of Composite Materials 35, no. 1 (January 1999): 19–32. http://dx.doi.org/10.1007/bf02260808.

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Eckert, J., M. Seidel, L. Q. Xing, I. Börner, and B. Weiβ. "Nanophase composites in easy glass forming systems." Nanostructured Materials 12, no. 1-4 (January 1999): 439–42. http://dx.doi.org/10.1016/s0965-9773(99)00153-1.

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WU, Z. S., MOHAMED F. M. FAHMY, and GANG WU. "DAMAGE-CONTROLLABLE STRUCTURE SYSTEMS USING FRP COMPOSITES." Journal of Earthquake and Tsunami 05, no. 03 (September 2011): 241–58. http://dx.doi.org/10.1142/s1793431111000966.

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Today, key infrastructures are required to have usability and repairability after earthquakes. Based on the requirements of the new codes, a mechanical model of damage-controllable structure using fiber reinforced polymers (FRPs) is proposed. Hence, the aim of the study is to examine the required recoverability for existing and new structures. First, an intensive study on the inelastic performance of FRP-retrofitted bridge columns was conducted. The study showed that recoverability of such columns is probable. Subsequently, an advanced FRP-strengthening design guideline that considers and evaluates structural recoverability is proposed. Second, innovative reinforcing rebars (steel fiber composite bars (SFCBs)) were developed to enhance the post-earthquake recoverability of new reinforced concrete (RC) bridges. The performance of RC bridge columns reinforced with two types of the innovative rebars, i.e. steel basalt-fiber composite bar (SBFCB) and steel carbon-fiber composite bar (SCFCB), were experimentally studied. Furthermore, numerical studies were conducted to investigate the performance of bond-controlled structures reinforced with the innovative rebars. Experimental results showed that SFCBs, as longitudinal reinforcement, guarantee the gradual increase of column strength in the inelastic stage and substantially mitigate column residual deformations. In the light of the analytical results, concrete-to-SFCB bond would be a reasonable tool to control the required recoverability, where both column post-yield stiffness and residual deformations could be controlled.

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Thomas, JP, SM Qidwai, WR Pogue, and GT Pham. "Multifunctional structure-battery composites for marine systems." Journal of Composite Materials 47, no. 1 (October 8, 2012): 5–26. http://dx.doi.org/10.1177/0021998312460262.

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Peutzfeldt, Anne. "Resin composites in dentistry: the monomer systems." European Journal of Oral Sciences 105, no. 2 (April 1997): 97–116. http://dx.doi.org/10.1111/j.1600-0722.1997.tb00188.x.

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da Costa, JB, F. Goncalves, and JL Ferracane. "Comparison of Two-Step Versus Four-Step Composite Finishing/Polishing Disc Systems: Evaluation of a New Two-Step Composite Polishing Disc System." Operative Dentistry 36, no. 2 (March 1, 2011): 205–12. http://dx.doi.org/10.2341/10-162-l.

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Clinical Relevance The two-step composite disc finishing/polishing system, Enhance Flex NST, can provide a nearly equivalent surface finish as two four-step systems on a variety of composites, in approximately half the time. All systems produce clinically acceptable gloss and surface roughness.

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Journal articles on the topic 'Composites systems'

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