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Tatsuya Hinoki - One of the best experts on this subject based on the ideXlab platform.

  • effects of Fiber Volume Fraction on the densification and mechanical properties of unidirectional sicf sic matrix composites
    Journal of The European Ceramic Society, 2021
    Co-Authors: Kazuya Shimoda, Tatsuya Hinoki
    Abstract:

    Abstract Unidirectional SiCf/SiC-matrix composites with a pyrocarbon interface were prepared by hot-pressing SiC nano-powder via a liquid phase of sintering additives under high temperature (1900 °C) and applied pressure (20 MPa). The SiC reinforcing Fiber Volume Fraction of the composites varied from 0 to 78 vol% and was found to have significant effects on densification and mechanical properties, where changes in failure mode, proportional limit stress, ultimate strength, and elastic modulus were observed. The mechanical properties were significantly enhanced with an increase in the Fiber Volume Fraction until a moderately high Fiber content was obtained, after which the ultimate strength of the composite degraded. These observations were related to the open porosity within the Fiber bundles. Further, Fiber strength was affected by Fiber damage caused by contact with the surrounding matrix due to poor densification of the SiC nano-powder.

  • Effects of Fiber Volume Fraction on the densification and mechanical properties of unidirectional SiCf/SiC-matrix composites
    Journal of the European Ceramic Society, 2021
    Co-Authors: Kazuya Shimoda, Tatsuya Hinoki
    Abstract:

    Abstract Unidirectional SiCf/SiC-matrix composites with a pyrocarbon interface were prepared by hot-pressing SiC nano-powder via a liquid phase of sintering additives under high temperature (1900 °C) and applied pressure (20 MPa). The SiC reinforcing Fiber Volume Fraction of the composites varied from 0 to 78 vol% and was found to have significant effects on densification and mechanical properties, where changes in failure mode, proportional limit stress, ultimate strength, and elastic modulus were observed. The mechanical properties were significantly enhanced with an increase in the Fiber Volume Fraction until a moderately high Fiber content was obtained, after which the ultimate strength of the composite degraded. These observations were related to the open porosity within the Fiber bundles. Further, Fiber strength was affected by Fiber damage caused by contact with the surrounding matrix due to poor densification of the SiC nano-powder.

  • high mechanical performance sic sic composites by nite process with tailoring of appropriate fabrication temperature to Fiber Volume Fraction
    Composites Science and Technology, 2009
    Co-Authors: Kazuya Shimoda, Akira Kohyama, Tatsuya Hinoki
    Abstract:

    Abstract Unidirectional SiC/SiC composites are prepared by nano-powder infiltration and transient eutectic-phase (NITE) process, using pyrolytic carbon (PyC)-coated Tyranno-SA SiC Fibers as reinforcement and SiC nano-powder with sintering additives for matrix formation. The effects of two kinds of Fiber Volume Fraction incorporating fabrication temperature were characterized on densification, microstructure and mechanical properties. Densification of the composites with low Fiber Volume Fraction (appropriately 30 vol%) was developed even at lower fabrication temperature of 1800 °C, and then saturated at 3rd stage of matrix densification corresponding to classic liquid phase sintering. Hence, densification of the composites with high Volume Fraction (above 50 vol%) became restricted because the many Fibers retarded the infiltration of SiC nano-powder at lower fabrication temperature of 1800 °C. When fabrication temperature increased by 1900 °C, densification of the composites was effectively enhanced in the intra-Fiber-bundles and simultaneously the interaction between PyC interface and matrix was strengthened. SEM observation on the fracture surface revealed that Fiber pull-out length was accordingly changed with fabrication temperature as well as Fiber Volume Fraction, which dominated tensile fracture behaviors. Through NITE process, SiC/SiC composites with two fracture types were successfully developed by tailoring of appropriate fabrication temperature to Fiber Volume Fraction as follows: (1) high ductility type and (2) high strength type.

  • High mechanical performance SiC/SiC composites by NITE process with tailoring of appropriate fabrication temperature to Fiber Volume Fraction
    Composites Science and Technology, 2009
    Co-Authors: Kazuya Shimoda, Akira Kohyama, Tatsuya Hinoki
    Abstract:

    Abstract Unidirectional SiC/SiC composites are prepared by nano-powder infiltration and transient eutectic-phase (NITE) process, using pyrolytic carbon (PyC)-coated Tyranno-SA SiC Fibers as reinforcement and SiC nano-powder with sintering additives for matrix formation. The effects of two kinds of Fiber Volume Fraction incorporating fabrication temperature were characterized on densification, microstructure and mechanical properties. Densification of the composites with low Fiber Volume Fraction (appropriately 30 vol%) was developed even at lower fabrication temperature of 1800 °C, and then saturated at 3rd stage of matrix densification corresponding to classic liquid phase sintering. Hence, densification of the composites with high Volume Fraction (above 50 vol%) became restricted because the many Fibers retarded the infiltration of SiC nano-powder at lower fabrication temperature of 1800 °C. When fabrication temperature increased by 1900 °C, densification of the composites was effectively enhanced in the intra-Fiber-bundles and simultaneously the interaction between PyC interface and matrix was strengthened. SEM observation on the fracture surface revealed that Fiber pull-out length was accordingly changed with fabrication temperature as well as Fiber Volume Fraction, which dominated tensile fracture behaviors. Through NITE process, SiC/SiC composites with two fracture types were successfully developed by tailoring of appropriate fabrication temperature to Fiber Volume Fraction as follows: (1) high ductility type and (2) high strength type.

Kazuya Shimoda - One of the best experts on this subject based on the ideXlab platform.

  • effects of Fiber Volume Fraction on the densification and mechanical properties of unidirectional sicf sic matrix composites
    Journal of The European Ceramic Society, 2021
    Co-Authors: Kazuya Shimoda, Tatsuya Hinoki
    Abstract:

    Abstract Unidirectional SiCf/SiC-matrix composites with a pyrocarbon interface were prepared by hot-pressing SiC nano-powder via a liquid phase of sintering additives under high temperature (1900 °C) and applied pressure (20 MPa). The SiC reinforcing Fiber Volume Fraction of the composites varied from 0 to 78 vol% and was found to have significant effects on densification and mechanical properties, where changes in failure mode, proportional limit stress, ultimate strength, and elastic modulus were observed. The mechanical properties were significantly enhanced with an increase in the Fiber Volume Fraction until a moderately high Fiber content was obtained, after which the ultimate strength of the composite degraded. These observations were related to the open porosity within the Fiber bundles. Further, Fiber strength was affected by Fiber damage caused by contact with the surrounding matrix due to poor densification of the SiC nano-powder.

  • Effects of Fiber Volume Fraction on the densification and mechanical properties of unidirectional SiCf/SiC-matrix composites
    Journal of the European Ceramic Society, 2021
    Co-Authors: Kazuya Shimoda, Tatsuya Hinoki
    Abstract:

    Abstract Unidirectional SiCf/SiC-matrix composites with a pyrocarbon interface were prepared by hot-pressing SiC nano-powder via a liquid phase of sintering additives under high temperature (1900 °C) and applied pressure (20 MPa). The SiC reinforcing Fiber Volume Fraction of the composites varied from 0 to 78 vol% and was found to have significant effects on densification and mechanical properties, where changes in failure mode, proportional limit stress, ultimate strength, and elastic modulus were observed. The mechanical properties were significantly enhanced with an increase in the Fiber Volume Fraction until a moderately high Fiber content was obtained, after which the ultimate strength of the composite degraded. These observations were related to the open porosity within the Fiber bundles. Further, Fiber strength was affected by Fiber damage caused by contact with the surrounding matrix due to poor densification of the SiC nano-powder.

  • high mechanical performance sic sic composites by nite process with tailoring of appropriate fabrication temperature to Fiber Volume Fraction
    Composites Science and Technology, 2009
    Co-Authors: Kazuya Shimoda, Akira Kohyama, Tatsuya Hinoki
    Abstract:

    Abstract Unidirectional SiC/SiC composites are prepared by nano-powder infiltration and transient eutectic-phase (NITE) process, using pyrolytic carbon (PyC)-coated Tyranno-SA SiC Fibers as reinforcement and SiC nano-powder with sintering additives for matrix formation. The effects of two kinds of Fiber Volume Fraction incorporating fabrication temperature were characterized on densification, microstructure and mechanical properties. Densification of the composites with low Fiber Volume Fraction (appropriately 30 vol%) was developed even at lower fabrication temperature of 1800 °C, and then saturated at 3rd stage of matrix densification corresponding to classic liquid phase sintering. Hence, densification of the composites with high Volume Fraction (above 50 vol%) became restricted because the many Fibers retarded the infiltration of SiC nano-powder at lower fabrication temperature of 1800 °C. When fabrication temperature increased by 1900 °C, densification of the composites was effectively enhanced in the intra-Fiber-bundles and simultaneously the interaction between PyC interface and matrix was strengthened. SEM observation on the fracture surface revealed that Fiber pull-out length was accordingly changed with fabrication temperature as well as Fiber Volume Fraction, which dominated tensile fracture behaviors. Through NITE process, SiC/SiC composites with two fracture types were successfully developed by tailoring of appropriate fabrication temperature to Fiber Volume Fraction as follows: (1) high ductility type and (2) high strength type.

  • High mechanical performance SiC/SiC composites by NITE process with tailoring of appropriate fabrication temperature to Fiber Volume Fraction
    Composites Science and Technology, 2009
    Co-Authors: Kazuya Shimoda, Akira Kohyama, Tatsuya Hinoki
    Abstract:

    Abstract Unidirectional SiC/SiC composites are prepared by nano-powder infiltration and transient eutectic-phase (NITE) process, using pyrolytic carbon (PyC)-coated Tyranno-SA SiC Fibers as reinforcement and SiC nano-powder with sintering additives for matrix formation. The effects of two kinds of Fiber Volume Fraction incorporating fabrication temperature were characterized on densification, microstructure and mechanical properties. Densification of the composites with low Fiber Volume Fraction (appropriately 30 vol%) was developed even at lower fabrication temperature of 1800 °C, and then saturated at 3rd stage of matrix densification corresponding to classic liquid phase sintering. Hence, densification of the composites with high Volume Fraction (above 50 vol%) became restricted because the many Fibers retarded the infiltration of SiC nano-powder at lower fabrication temperature of 1800 °C. When fabrication temperature increased by 1900 °C, densification of the composites was effectively enhanced in the intra-Fiber-bundles and simultaneously the interaction between PyC interface and matrix was strengthened. SEM observation on the fracture surface revealed that Fiber pull-out length was accordingly changed with fabrication temperature as well as Fiber Volume Fraction, which dominated tensile fracture behaviors. Through NITE process, SiC/SiC composites with two fracture types were successfully developed by tailoring of appropriate fabrication temperature to Fiber Volume Fraction as follows: (1) high ductility type and (2) high strength type.

Magdi El Messiry - One of the best experts on this subject based on the ideXlab platform.

  • Theoretical determination of the Fiber Volume Fraction distribution for natural Fiber fabric reinforced polymer composite
    Journal of Industrial Textiles, 2017
    Co-Authors: Magdi El Messiry
    Abstract:

    The present work attempts to understand the inter-relation between the spun yarn Fiber Volume Fraction and the fabric Fiber Volume Fraction when adapted in the reinforced polymer composite. The yar...

  • study pultruded jute fabric effect on the cementitious thin composites mechanical properties with low Fiber Volume Fraction
    alexandria engineering journal, 2017
    Co-Authors: Magdi El Messiry, Shaimaa Eltarfawy, Rania El Deeb
    Abstract:

    Abstract The objective of this work was to study the influence of low Fiber Volume Fraction on the mechanical properties of the Jute fabric reinforced cementitious composites, suggesting the thin sheet of pultruded fabric instead of Jute as a suitable solution for the forming complex matrix shapes. The present work investigates the pultrusion of a Jute fabrics reinforced by the polymeric matrix material, which protects the Jute fabrics and improves the durability of Fiber cement sheets. Different Fiber Volume Fraction as well as polymeric matrix material blending ratios were investigated through the pultrusion technique and compared with the control untreated Jute fabrics reinforced cementations composites. Microstructure characteristics of the fabric–matrix interface were also explored and correlated with the mechanical properties of the pultruded Jute fabrics reinforced cementations composite. It was found that an improvement in the behavior of mechanical properties of the cement composite with pultruded Jute fabrics compared to similar composites. Acceptable correlations were found on the mechanical properties of the composite, particularly bending stiffness. Pultrusion Jute reinforced polymeric matrix material increases the tensile stress, the modulus of elasticity, and the flexure strength than in control untreated Jute fabrics reinforced cementations composites.

  • Theoretical analysis of natural Fiber Volume Fraction of reinforced composites
    Alexandria Engineering Journal, 2013
    Co-Authors: Magdi El Messiry
    Abstract:

    Abstract In the latest years industry is attempting to decrease the dependence on petroleum based fuels and products due to the increased environmental consciousness. This is leading to the need to investigate environmentally friendly, sustainable materials to replace existing ones, and to solve the problems of recycling of agriculture waste. We are trying to understand composites due to their high potential as a material with suitable strength, low weight and low deformation. Fiber and epoxy as lamina are used to form composite laminates with desired directional properties. Mechanical properties for composites are derived starting from properties of Fiber and matrix, using the rule of mixtures, and the Fiber Volume Fraction plays a significant role in the determination of the mechanical properties. In this work the value of the Fiber Volume Fraction is determined considering fibrous structure constituent, random Fiber, yarns or fabric.

Ray S. Fertig - One of the best experts on this subject based on the ideXlab platform.

  • effects of thickness and Fiber Volume Fraction variations on strain field inhomogeneity
    Composites Part A-applied Science and Manufacturing, 2015
    Co-Authors: Eric M. Jensen, David Leonhardt, Ray S. Fertig
    Abstract:

    Abstract In this study, variations in thickness and Fiber Volume Fraction are investigated as causes of elastic strain inhomogeneity in composite laminates under an applied transverse load. Standard carbon/epoxy tensile specimens were fabricated from unidirectional pre-impregnated material using two different manufacturing techniques that produced two different levels of surface roughness. Fiber Volume Fraction variation was computed by analyzing optical micrographs of the samples. During loading and unloading of the samples two-dimensional surface strain fields were measured on the specimen using digital image correlation. It was shown that in both cases the strain in the specimen is not uniform, as is generally assumed. Using finite element simulations the effects of Fiber Volume Fraction variation and thickness variation were modeled individually and in combination. The simulations agree well with the experimental results and suggest that thickness variations are the dominant mechanisms involved in this elastic strain inhomogeneity.

  • Multiscale Stochastic Analysis of FRP based on variability in Fiber Volume Fraction, epoxy stiffness and strength
    56th AIAA ASCE AHS ASC Structures Structural Dynamics and Materials Conference, 2015
    Co-Authors: Seyed Hamid Reza Sanei, Eric M. Jensen, Ray S. Fertig
    Abstract:

    For accurate prediction of composite failure, microstructural variability must be considered. The distribution of epoxy stiffness and hardness were determined by nanoindentation and used in stochastic finite element modeling. Another key microstructural feature, Fiber Volume Fraction variability, was determined by image processing of an SEM image. Stochastic failure analysis was implemented on a micromechanics model of hexagonal Fiber packing to predict the initiation of failure under multiaxial loadings. Three failure criteria were employed for characterization of failure: maximum stress, von Mises, and Christensen. Failure envelopes were developed for stochastic and average models. The results revealed that the variability in epoxy strength influence the failure behavior significantly, whereas, stiffness variability has minimal effect.

  • Uncorrelated Volume element for stochastic modeling of microstructures based on local Fiber Volume Fraction variation
    Composites Science and Technology, 2015
    Co-Authors: Seyed Hamid Reza Sanei, Ray S. Fertig
    Abstract:

    Abstract One source of microstructural variability in Fiber reinforced polymers is variability in Fiber Volume Fraction. Despite large scatter in Fiber Volume Fraction, an average value is usually reported without any consideration regarding the variability. Significant variation in Fiber Volume Fraction across the sample reveals that homogeneity throughout the sample is a poor assumption and the commonly employed representative Volume element is a poor representation of real microstructures. In this work, the distributions of Fiber Volume Fraction at different length scales are investigated. The variation in distributions suggests that a length scale-dependent distribution must be selected in probabilistic analysis. A cross-correlation between Fiber Volume Fractions of nearest neighbors was computed and an uncorrelated Volume element (UVE) is introduced for the length scale at which Fiber Volume Fractions become uncorrelated. The concept of a UVE enables random attribution of properties in stochastic modeling.

Aidy Ali - One of the best experts on this subject based on the ideXlab platform.

  • Effects of Fiber Volume Fraction on Unidirectional Kenaf/Epoxy Composites: The Transition Region
    Polymer-Plastics Technology and Engineering, 2011
    Co-Authors: Abdul Hakim Abdullah, Abdan Khalina, Aidy Ali
    Abstract:

    This article presents the effects of Fiber Volume Fraction on the existence of a transition region in unidirectional kenaf/epoxy composites. The composites were made from hand Lay-up techniques, with three formulations of Fiber Volume Fraction employed: 0% (neat), 15% and 45%. The results showed that tensile properties such as tensile strength and modulus of elasticity increased as the Fiber Volume increased. The stress-strain curves showed that the kenaf/epoxy composites exhibited bi-linear responses with reductions in the modulus of elasticity. Surface morphology aided by a scanning electron microscope (SEM) revealed that the reduction in the modulus of elasticity was due to matrix cracking.

  • effects of Fiber Volume Fraction on unidirectional kenaf epoxy composites the transition region
    Polymer-plastics Technology and Engineering, 2011
    Co-Authors: Abdul Hakim Abdullah, Abdan Khalina, Aidy Ali
    Abstract:

    This article presents the effects of Fiber Volume Fraction on the existence of a transition region in unidirectional kenaf/epoxy composites. The composites were made from hand Lay-up techniques, with three formulations of Fiber Volume Fraction employed: 0% (neat), 15% and 45%. The results showed that tensile properties such as tensile strength and modulus of elasticity increased as the Fiber Volume increased. The stress-strain curves showed that the kenaf/epoxy composites exhibited bi-linear responses with reductions in the modulus of elasticity. Surface morphology aided by a scanning electron microscope (SEM) revealed that the reduction in the modulus of elasticity was due to matrix cracking.