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Jan-anders E. Månson - One of the best experts on this subject based on the ideXlab platform.

  • Stamp forming of carbon fibre/PA12 composites – A comparison of a reactive impregnation process and a Commingled Yarn system
    Composites Science and Technology, 2006
    Co-Authors: Martyn Douglas Wakeman, Pierre-etienne Bourban, Jan-anders E. Månson, L. Zingraff, P. Blanchard
    Abstract:

    Two forms of carbon fibre reinforced polyamide 12 (PA12) were compared during non-isothermal stamp forming. The first was a stretch broken Commingled Yarn woven into a fabric, studied at three initial preconsolidation levels. The second was produced by in situ anionic polymerisation of lactam 12 (APLC12) in a carbon fibre textile, using a thermoplastic resin transfer moulding (TP-RTM) process. A processing window was defined for TP-RTM based upon non-isothermal polymerisation kinetics. For each material form, the effects of stamping parameters on flat plaque properties were examined. For Commingled materials, the influence of preheat temperature and the initial preconsolidation level dominated, with preconsolidated materials deconsolidating strongly during the preheat cycle. For CF/APLC12 materials, the effect of material temperature and tool temperature dominated and reduced deconsolidation occurred. Hemisphere forming was enabled by stretch-broken Yarn but was possible for both material classes. Over-injection moulding of recompounded CF/APLC12 composite onto stamped CF/APLC12 plate was performed, demonstrating a closed-loop recycling process.

  • Stamp-forming of carbon fibre PA12 composite preforms
    2002
    Co-Authors: Martyn Douglas Wakeman, Pierre-etienne Bourban, Jan-anders E. Månson, L. Zingraff, M. Kohler, P. Blanchard
    Abstract:

    Keywords: non-isothermal stamping ; reactive impregnation ; Commingled Yarn ; deconsolidation Reference EPFL-CONF-179227 Record created on 2012-06-29, modified on 2016-08-09

  • Numerical Analysis of the Dimensional Stability of Thermoplastic Composites Using a Thermoviscoelastic Approach
    Journal of Composite Materials, 2002
    Co-Authors: Byeong-sam Kim, N. Bernet, P. Sunderland, Jan-anders E. Månson
    Abstract:

    The dimensional stability of V-shaped composite parts made from polyamide-12/carbon fibre (PA12/CF) Commingled Yarn has been studied. An anisotropic, thermoviscoelastic material model was implemented in a finite element solver to predict the internal stresses induced during the processing of the composite. Excellent correlation was found between predicted and experimentally measured stress profiles for compression-moulded parts. The stresses were related to the dimensional stability of the parts after demoulding and the effect of key processing parameters on dimensional stability was investigated.

  • An integrated cost and consolidation model for Commingled Yarn based composites
    Composites Part A: Applied Science and Manufacturing, 2002
    Co-Authors: N. Bernet, Pierre-etienne Bourban, Martyn Douglas Wakeman, Jan-anders E. Månson
    Abstract:

    In order to assess the potential of Commingled Yarns for cost-effective manufacturing of thermoplastic composites, an integrated cost and consolidation model has been developed. The cost estimation procedure and the consolidation model are applicable to a wide variety of composite processing techniques. Interaction between the cost and consolidation models allowed the determination of the processing conditions necessary to achieve the desired quality at a minimum manufacturing cost. It also permitted study of the material and cost responses to a particular set of processing parameters. This was illustrated for a generic composite hook manufactured by a novel technique, referred to as integrated processing, utilising robotic placement of Commingled Yarns of carbon and polyamide 12 fibres and over-injection moulding. Comparison with hooks processed by unreinforced polymer via injection moulding also demonstrated the potential of the integrated processing technique for the production of complex-shaped composites with increased performance-to-cost ratio.

  • Commingled Yarn composites for rapid processing of complex shapes
    Composites Part A: Applied Science and Manufacturing, 2001
    Co-Authors: N. Bernet, Pierre-etienne Bourban, Véronique Michaud, Jan-anders E. Månson
    Abstract:

    Abstract Commingled Yarns of reinforcing and thermoplastic fibres offer a potential for low-cost manufacturing of complex-shaped composite parts, due to reduced impregnation times and applied pressures during processing. In order to benefit from this competitive advantage, the process parameters governing consolidation must be controlled. In this study, a consolidation model, previously validated for unidirectional Commingled Yarn fabrics processed isothermally in a flat matched-die mould, is applied to three other processing techniques capable of producing complex-shaped composites. Tubes of braided Commingled Yarns were manufactured by bladder inflation moulding. Selectively reinforced polymeric parts were processed by compression–injection moulding. Stamp forming was also used to allow high-speed processing of Commingled Yarn-based laminates. Besides particular stamp forming cases, for which part deconsolidation occurred, the model predictions were in good agreement with the void content values obtained from specimens consolidated under different processing conditions. This suggests that the consolidation model can be successfully applied to a wide range of Yarn architectures and processing techniques.

Liyan Liu - One of the best experts on this subject based on the ideXlab platform.

  • Research on properties of thermoplastic composites reinforced by flax fabrics
    Materials & Design, 2008
    Co-Authors: Gu Huang, Liyan Liu
    Abstract:

    Flax Yarn and PP (polypropylene) filaments were twisted together to form a Commingled Yarn in a fancy twister. Fabrics with plain and twill weaves were woven by using the plied Yarn. Composites with five layers of identical fabric weaves were fabricated in a heating press. In this way the reinforcement fibre (the flax) and the matrix (the PP) in the composite may be evenly blended. With complete covering on the flax Yarn surface by the PP filaments, abrasion on the reinforcement material in the following processes would be alleviated. Tensile strength test was carried out and the failure mechanism was analyzed, structure of the broken end of the composites was observed by SEM (Scanning electron microscope).

Long Hai-ru - One of the best experts on this subject based on the ideXlab platform.

  • Investigation on the Tensile Properties of Knitted Fabric Reinforced Composites made from GF-PP Commingled Yarn Preforms with Different Loop Densities
    Journal of Thermoplastic Composite Materials, 2006
    Co-Authors: Fan Zaixia, Zhangyu, Chen Yan-mo, Long Hai-ru
    Abstract:

    The influence of the loop density of rib 1 : 1 fabric preform made from GF-PP Commingled Yarn on the tensile properties of the composites is investigated. Six samples of rib 1 : 1 fabric preform with different loop densities are studied. It has been found that the tensile strength of composites show an increase followed by a light decrease as the loop density of the rib 1 : 1 fabric preform increases, while the fracture strain just presented a contrary variation tendency. Fiber strength efficiency (FSE) is introduced to explain this phenomenon. Also, the inherent characteristic of loop structure, the homogeneity of fiber-matrix distribution in composites, and the continuousness of the reinforcement are taken into consideration to explain this.

  • Tensile Properties of Glass Fiber Knitted Fabric Reinforced Polypropylene Composite Made from GF/PP Commingled Yarn Affected by Prestretching:
    Journal of Reinforced Plastics and Composites, 2006
    Co-Authors: Fan Zaixia, Zhangyu, Chen Yan-mo, Long Hai-ru
    Abstract:

    The effects of prestretching of rib 1: 1 knitted fabric preform on the tensile properties of GF/PP composites are investigated in this study. The preform is made from GF/PP Commingled Yarn. As far as tensile stiffness and tensile strength are concerned, there is a critical value of prestretch ratio. An increase in the prestretch ratio within the range of this critical value increases both the tensile stiffness and the tensile strength. If the prestretch ratio goes beyond this critical value and continues to increase, both tensile stiffness and tensile strength display a tendency of slight decrease because of the break of more glass fibers. The failure strain of the composites decreases with the increase of the prestretch ratio because of the decrease of the stretchability of the knitted reinforcements.

  • Research on the drawtexturing properties of thermoplastic weft knitting composite material
    Progress in Textile Science & Technology, 2006
    Co-Authors: Long Hai-ru
    Abstract:

    This paper is concerned with a composite consisting of glass and polypropylene Commingled Yarn.The plain and rib weft-knitted fabric were made of this type of Commingled Yarn,and then the hot-press method was used to produce composites.Tensile tests on composites samples were carried out to examine their deformation properties.At the same time,the changes of meso-structure were recorded by photographing.The experiment results indicate the deformation properties of composites are affected by fiber volume fraction、fabric structure and parameter、tensile direction etc.

  • A Study on the Tensile Properties of Weft-knitted Structural Composites from Glass Fiber and PP Commingled Yarns
    Journal of Donghua University, 2006
    Co-Authors: Long Hai-ru
    Abstract:

    Plain and rib knitted fabrics were produced from polypropylene and glass fiber Commingled Yarn on a flat knitting machine. The composites were formed by the hot press technology. Then the tensile tests were carried out on the universal machine. The results indicate that of two kinds of composites differ in the tensile properties because of fabric structure, and for the same structure composites, the tensile properties have relation with loading orientation. The reasons caused the different tensile results were analyzed, which is valuable for the design and produce of weft-knitted structural composites.

Tatsuki Matsuo - One of the best experts on this subject based on the ideXlab platform.

  • Compression Molding and Mechanical Properties of Green-Composite Based on Ramie/PLA Non-Twisted Commingled Yarn
    Journal of the Society of Materials Science Japan, 2004
    Co-Authors: Teruo Kimura, Tatsuki Matsuo, Masahiro Kurata, Hirokazu Matsubara, Tadayuki Sakobe
    Abstract:

    In recent years, increased emphasis has been placed on developing the environmentally friendly biodegradable composites with the goal of protecting the environment. In this paper, the ramie/PLA biodegradable composites were molded and their mechanical behaviors were discussed. The non-twisted Commingled Yarn constructed with ramie and PLA fibers as reinforcement and matrix respectively was pre-molded to achieve the good penetration and dispersion of matrix and reinforcement. The compression molding with heating was performed to melt PLA fibers, and the green-composites reinforced by uni-directionally oriented ramie fiber were obtained. The volume fraction of ramie fiber was varied for wide range, and the tensile, bending and impact tests were performed for the molded composite. Especially, the results of bending test were compared with those of the composite based on the usual twisted Commingled Yarn. The microscopic observation was also carried out to examine the fracture mode of composite. It is concluded here that the fairly higher tensile and bending strength and modulus were obtained for our molded composites. This may be caused by the good penetration of matrix between fibers, good dispersion of fibers and also the uni-directionally oriented fibers. Especially, the impact value was fairly larger than that of PLA matrix at the higher volume fraction of ramie fiber.

  • compression molding and mechanical properties of green composite based on ramie pla non twisted Commingled Yarn
    Journal of The Society of Materials Science Japan, 2004
    Co-Authors: Teruo Kimura, Tatsuki Matsuo, Masahiro Kurata, Hirokazu Matsubara, Tadayuki Sakobe
    Abstract:

    In recent years, increased emphasis has been placed on developing the environmentally friendly biodegradable composites with the goal of protecting the environment. In this paper, the ramie/PLA biodegradable composites were molded and their mechanical behaviors were discussed. The non-twisted Commingled Yarn constructed with ramie and PLA fibers as reinforcement and matrix respectively was pre-molded to achieve the good penetration and dispersion of matrix and reinforcement. The compression molding with heating was performed to melt PLA fibers, and the green-composites reinforced by uni-directionally oriented ramie fiber were obtained. The volume fraction of ramie fiber was varied for wide range, and the tensile, bending and impact tests were performed for the molded composite. Especially, the results of bending test were compared with those of the composite based on the usual twisted Commingled Yarn. The microscopic observation was also carried out to examine the fracture mode of composite. It is concluded here that the fairly higher tensile and bending strength and modulus were obtained for our molded composites. This may be caused by the good penetration of matrix between fibers, good dispersion of fibers and also the uni-directionally oriented fibers. Especially, the impact value was fairly larger than that of PLA matrix at the higher volume fraction of ramie fiber.

  • The Influence of Cooling Conditions on the Mechanical Properties of Commingled Yarn Composites
    Journal of Thermoplastic Composite Materials, 1996
    Co-Authors: G. O. Shonaike, Zenichiro Maekawa, Hiroyuki Hamada, Masaou Matsuda, T. Yuba, Tatsuki Matsuo
    Abstract:

    The influence of cooling conditions on the bending properties and Mode I interlaminar fracture toughness of Commingled PET/GF and PA6/GF composites was investigated. The morphology and thermal properties of the composites were studied using scanning electron microscopy (SEM) and differential scanning calorimetry (DSC).The results show that cooling conditions had no major effect on bending properties, but the fracture toughness (GC) was affected; i.e., fracture toughness of gradual cooling was lower than rapid cooling. The bending properties are not significantly affected by crystallinity, but GC is strongly influenced by the level of crystallinity in the matrix resin.

  • The effect of impregnation technique on bending properties of glass fiber reinforced polyethylene terephthalate composites
    Composite Interfaces, 1994
    Co-Authors: G. O. Shonaike, Zenichiro Maekawa, Hiroyuki Hamada, Masaou Matsuda, Tatsuki Matsuo
    Abstract:

    An investigation was conducted to check the effect of impregnation techniques on bending properties of glass fiber reinforced polyethylene terephthalate (PET). The impregnation techniques used Commingled Yarn and parallel Yarn methods. Holding time during fabrication varied between 1 and 20 min. The morphology and thermal properties of the composites were studied by using scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The results showed that Commingled Yarn can be fabricated at low pressure with good impregnation characteristics whilst parallel Yarn requires a high pressure before a good impregnation of matrix resin into fiber can be achieved. Bending properties of Commingled Yarn composites were higher than those of parallel Yarn composites. This was due to different impregnation techniques. The crystallinity of the matrix resin was not affected by different holding time during compression molding.

  • Mechanical Behavior and Fracture Mechanism of Thermoplastic Composites with Commingled Yarn
    Journal of Reinforced Plastics and Composites, 1993
    Co-Authors: Akihiro Fujita, Zenichiro Maekawa, Hiroyuki Hamada, Masaou Matsuda, Tatsuki Matsuo
    Abstract:

    Commingled Yarn has been developed in order to overcome the difficulties that are experienced when thermoplastic materials are impregnated to reinforce composite materials. Braid is one of the preforming techniques in the reinforcement configuration of composite materials. In this article, tensile properties of thermoplastic braided composites with Commingled Yarn as structural members are discussed. It is clear that the molding of thermoplastic braided composites with Commingled Yarn could be performed in compara tively low molding pressure and short holding time. The middle-end-fiber and axial fiber were used to raise the tensile strength of thermoplastic braided composites. Thermoplastic braided composites with the Commingled Yarn-using glass fiber bundle as middle-end- fiber and axial fiber—had superior tensile properties.

N. Bernet - One of the best experts on this subject based on the ideXlab platform.

  • Numerical Analysis of the Dimensional Stability of Thermoplastic Composites Using a Thermoviscoelastic Approach
    Journal of Composite Materials, 2002
    Co-Authors: Byeong-sam Kim, N. Bernet, P. Sunderland, Jan-anders E. Månson
    Abstract:

    The dimensional stability of V-shaped composite parts made from polyamide-12/carbon fibre (PA12/CF) Commingled Yarn has been studied. An anisotropic, thermoviscoelastic material model was implemented in a finite element solver to predict the internal stresses induced during the processing of the composite. Excellent correlation was found between predicted and experimentally measured stress profiles for compression-moulded parts. The stresses were related to the dimensional stability of the parts after demoulding and the effect of key processing parameters on dimensional stability was investigated.

  • An integrated cost and consolidation model for Commingled Yarn based composites
    Composites Part A: Applied Science and Manufacturing, 2002
    Co-Authors: N. Bernet, Pierre-etienne Bourban, Martyn Douglas Wakeman, Jan-anders E. Månson
    Abstract:

    In order to assess the potential of Commingled Yarns for cost-effective manufacturing of thermoplastic composites, an integrated cost and consolidation model has been developed. The cost estimation procedure and the consolidation model are applicable to a wide variety of composite processing techniques. Interaction between the cost and consolidation models allowed the determination of the processing conditions necessary to achieve the desired quality at a minimum manufacturing cost. It also permitted study of the material and cost responses to a particular set of processing parameters. This was illustrated for a generic composite hook manufactured by a novel technique, referred to as integrated processing, utilising robotic placement of Commingled Yarns of carbon and polyamide 12 fibres and over-injection moulding. Comparison with hooks processed by unreinforced polymer via injection moulding also demonstrated the potential of the integrated processing technique for the production of complex-shaped composites with increased performance-to-cost ratio.

  • Commingled Yarn composites for rapid processing of complex shapes
    Composites Part A: Applied Science and Manufacturing, 2001
    Co-Authors: N. Bernet, Pierre-etienne Bourban, Véronique Michaud, Jan-anders E. Månson
    Abstract:

    Abstract Commingled Yarns of reinforcing and thermoplastic fibres offer a potential for low-cost manufacturing of complex-shaped composite parts, due to reduced impregnation times and applied pressures during processing. In order to benefit from this competitive advantage, the process parameters governing consolidation must be controlled. In this study, a consolidation model, previously validated for unidirectional Commingled Yarn fabrics processed isothermally in a flat matched-die mould, is applied to three other processing techniques capable of producing complex-shaped composites. Tubes of braided Commingled Yarns were manufactured by bladder inflation moulding. Selectively reinforced polymeric parts were processed by compression–injection moulding. Stamp forming was also used to allow high-speed processing of Commingled Yarn-based laminates. Besides particular stamp forming cases, for which part deconsolidation occurred, the model predictions were in good agreement with the void content values obtained from specimens consolidated under different processing conditions. This suggests that the consolidation model can be successfully applied to a wide range of Yarn architectures and processing techniques.

  • Process and cost modeling of Commingled Yarn based laminates
    1999
    Co-Authors: N. Bernet, Pierre-etienne Bourban, Jan-anders E. Månson
    Abstract:

    Keywords: Commingled Yarn ; process modeling ; cost Reference EPFL-CONF-178803 Record created on 2012-06-29, modified on 2016-08-09

  • Cost-effective manufacturing of hollow composite structures by bladder inflation moulding
    1999
    Co-Authors: N. Bernet, Pierre-etienne Bourban, Jan-anders E. Månson
    Abstract:

    Keywords: blader inflation moulding ; manufacturing cost ; consolidation model ; Commingled Yarn Reference EPFL-CONF-178802 Record created on 2012-06-29, modified on 2016-08-09