The Experts below are selected from a list of 11856 Experts worldwide ranked by ideXlab platform

W.j. Cantwell - One of the best experts on this subject based on the ideXlab platform.

  • deformation behaviour of steel srpp fibre metal laminate characterised by evolution of surface strains
    Advances in aircraft and spacecraft science, 2016
    Co-Authors: Jae Nam, W.j. Cantwell, Adrian Lowe, Raj Das, Shankar Kalyanasundaram
    Abstract:

    Climate changes brought on by human interventions have proved to be more devastating than predicted during the recent decades. Recognition of seriousness of the situation has led regulatory organisations to impose strict targets on allowable carbon dioxide emissions from automotive vehicles. As a possible solution, it has been proposed that Fibre Metal Laminate (FML) system is used to reduce the weight of future vehicles. To facilitate this investigation, FML based on steel and Self-Reinforced Polypropylene was stamp formed into dome shapes under different blank holder forces (BHFs) at room temperature and its forming behaviour analysed. An open-die configuration was used in a hydraulic press so that a 3D photogrammetric measurement system (ARAMIS) could capture real-time surface strains. This paper presents findings on strain evolutions at different points along and at 45o to fibre directions of circular FML blank, through various stages of forming. It was found initiation and rate of deformation varied with distance from the pole, that the mode of deformations range from biaxial stretching at the pole to drawing towards flange region, at decreasing magnitudes away from the pole in general. More uniform strain distribution was observed for the FML compared to that of plain steel and the most significant effects of BHF were its influence on forming depth and level of strain reached before failure.

  • interfacial fracture of the fibre metal laminates based on fibre reinforced thermoplastics
    Materials & Design, 2015
    Co-Authors: M R Abdullah, W.j. Cantwell, Yunan Prawoto
    Abstract:

    Abstract As the adhesion quality plays an important role in determining the mechanical performance and environmental stability of most types of fibre-metal laminates (FMLs), investigating the interfacial fracture properties becomes one of the key factors for the improvement. Adhesion of a Self-Reinforced Polypropylene (SRPP) and glass fibre reinforced Polypropylene (GFPP) based FML is evaluated experimentally. Single Cantilever Beam (SCB) tests were performed to access interfacial fracture energy (Gc) of the bi-material laminates and their associated interlayer materials. Simulations mimicking the experiments were also performed. The energy needed to fracture was obtained experimentally and also via stress intensity factor from the simulations. The test results show that good adhesion between the aluminium and fibre reinforced thermoplastics can be achieved using a sulphuric acid anodising surface pre-treatment. Further examination has shown that the edges of the test samples highlighted the presence of significant fibre bridging in the SRPP and plastics deformation in the GFPP.

  • effect of blank holder force on strain evolution of forming of steel srpp fibre metal laminate
    The 8th Australasian Congress on Applied Mechanics 2014 (ACAM 8), 2014
    Co-Authors: Jae Nam, W.j. Cantwell, Adrian Lowe, Raj Das, Shankar Kalyanasundaram
    Abstract:

    Climate changes brought on by human interventions have proved to be more devastating than predicted during the recent decades. Recognition of seriousness of the situation has led regulatory organisations to impose strict targets on allowable carbon dioxide emissions from automotive vehicles. As a possible solution, it has been proposed that Fibre Metal Laminate (FML) system is used to reduce the weight of future vehicles. To facilitate this investigation, FML based on steel and Self-Reinforced Polypropylene was stamp formed into dome shapes under different blank holder forces (BHFs) at room temperature and its forming behaviour analysed. An open-die configuration was used in a hydraulic press so that a 3D photogrammetric measurement system (ARAMIS) could capture real-time surface strains. This paper presents findings on strain evolutions at different points along and at 45 to fibre directions of circular FML blank, through various stages of forming. It was found initiation and rate of deformation varied with distance from the pole, that the mode of deformations range from biaxial stretching at the pole to drawing towards flange region, at decreasing magnitudes away from the pole in general. More uniform strain distribution was observed for the FML compared to that of plain steel and the most significant effects of BHF were its influence on forming depth and level of strain reached before failure.

  • mechanical properties of a novel fiber metal laminate based on a Polypropylene composite
    Mechanics of Materials, 2009
    Co-Authors: J G Carrillo, W.j. Cantwell
    Abstract:

    Fiber–metal laminates (FMLs) are a relatively new type of material developed from the need to develop high performance lightweight structures with excellent properties under tensile, flexure and impact conditions. The first generation of FMLs was based on thermosetting matrices, typically epoxy resins. Recently, new types of FMLs are emerging as a result of the demand for more efficient and lightweight materials for use in the automotive and aerospace industries. This study characterizes the mechanical properties of a new type of thermoplastic-matrix FML based on a Self-Reinforced Polypropylene (SRPP) composite and an aluminum alloy. This FML is manufactured in a simple compression-molding process, allowing it to subsequently be re-shaped according to operational requirements. This paper presents the findings of a study conducted to investigate the mechanical properties for this lightweight thermoplastic FML, investigating its properties in tension, flexure and impact.

Hong Tae Kang - One of the best experts on this subject based on the ideXlab platform.

  • mechanical behavior of lightweight thermoplastic fiber metal laminates
    Journal of Materials Processing Technology, 2007
    Co-Authors: G Reyes, Hong Tae Kang
    Abstract:

    Abstract Lightweight thermoplastic-based fiber–metal laminates were developed based on Self-Reinforced Polypropylene and glass fiber-reinforced Polypropylene composite materials and an aluminum alloy 2024-T3. The laminates were manufactured using a fast one-step cold press manufacturing procedure. The mechanical behavior of the laminates was then investigated under tensile and fatigue loading conditions. The tensile properties of the plain aluminum, the composite materials and the thermoplastic fiber–metal laminates were investigated at quasi-static rates of loading. The fatigue tests were also conducted under load control in accordance with the ASTM E466 standard procedure. Various loading cycles were employed for the fatigue tests in order to minimize the possibility of heat generation on the composite materials. Load levels of 40, 60 and 80% of yield strength of each thermoplastic fiber–metal laminate panel were applied with zero to max loading. The glass fiber-reinforced Polypropylene hybrid systems exhibited higher fatigue strength than the Self-Reinforced Polypropylene-based fiber–metal laminates. Then, punch–stretch forming tests were performed in order to evaluate the formability of the hybrid systems. Experimental results revealed that the Self-Reinforced thermoplastic composite-based fiber–metal laminate exhibit excellent forming properties similar to that of the monolithic aluminum alloy of comparable thickness.

  • mechanical behavior of lightweight thermoplastic fiber metal laminates
    Journal of Materials Processing Technology, 2007
    Co-Authors: G Reyes, Hong Tae Kang
    Abstract:

    Abstract Lightweight thermoplastic-based fiber–metal laminates were developed based on Self-Reinforced Polypropylene and glass fiber-reinforced Polypropylene composite materials and an aluminum alloy 2024-T3. The laminates were manufactured using a fast one-step cold press manufacturing procedure. The mechanical behavior of the laminates was then investigated under tensile and fatigue loading conditions. The tensile properties of the plain aluminum, the composite materials and the thermoplastic fiber–metal laminates were investigated at quasi-static rates of loading. The fatigue tests were also conducted under load control in accordance with the ASTM E466 standard procedure. Various loading cycles were employed for the fatigue tests in order to minimize the possibility of heat generation on the composite materials. Load levels of 40, 60 and 80% of yield strength of each thermoplastic fiber–metal laminate panel were applied with zero to max loading. The glass fiber-reinforced Polypropylene hybrid systems exhibited higher fatigue strength than the Self-Reinforced Polypropylene-based fiber–metal laminates. Then, punch–stretch forming tests were performed in order to evaluate the formability of the hybrid systems. Experimental results revealed that the Self-Reinforced thermoplastic composite-based fiber–metal laminate exhibit excellent forming properties similar to that of the monolithic aluminum alloy of comparable thickness.

Shankar Kalyanasundaram - One of the best experts on this subject based on the ideXlab platform.

  • deformation behaviour of steel srpp fibre metal laminate characterised by evolution of surface strains
    Advances in aircraft and spacecraft science, 2016
    Co-Authors: Jae Nam, W.j. Cantwell, Adrian Lowe, Raj Das, Shankar Kalyanasundaram
    Abstract:

    Climate changes brought on by human interventions have proved to be more devastating than predicted during the recent decades. Recognition of seriousness of the situation has led regulatory organisations to impose strict targets on allowable carbon dioxide emissions from automotive vehicles. As a possible solution, it has been proposed that Fibre Metal Laminate (FML) system is used to reduce the weight of future vehicles. To facilitate this investigation, FML based on steel and Self-Reinforced Polypropylene was stamp formed into dome shapes under different blank holder forces (BHFs) at room temperature and its forming behaviour analysed. An open-die configuration was used in a hydraulic press so that a 3D photogrammetric measurement system (ARAMIS) could capture real-time surface strains. This paper presents findings on strain evolutions at different points along and at 45o to fibre directions of circular FML blank, through various stages of forming. It was found initiation and rate of deformation varied with distance from the pole, that the mode of deformations range from biaxial stretching at the pole to drawing towards flange region, at decreasing magnitudes away from the pole in general. More uniform strain distribution was observed for the FML compared to that of plain steel and the most significant effects of BHF were its influence on forming depth and level of strain reached before failure.

  • induced forming modes in a pre consolidated woven Polypropylene composite during stretch forming process at room temperature i experimental studies
    Composites Part A-applied Science and Manufacturing, 2015
    Co-Authors: Nima Akhavan Zanjani, Anthony Sexton, Shankar Kalyanasundaram
    Abstract:

    Abstract In the current study, rectangular specimens of pre-consolidated woven Self-Reinforced Polypropylene (SRPP) possessing different fibre orientations and aspect ratios were stretch formed in an open die. Induced displacements were recorded by an in-situ 3D photogrammetric measurement system. Resultant principal strains were investigated to clarify the role of different deformation modes during stamp forming. The dependency of induced deformation modes to the specimens’ geometries was studied. A novel path/deformation dependent failure criterion was established to distinguish between safe and failed regions of SRPP in a stamping process and to elucidate the dependency between failure and induced forming modes in a woven composite. The experimental results highlighted the suitability of consolidated SRPP to be formed into complex doubly curved geometries by the stamp forming process at room temperature. It was found that required forming depths could be achieved if a proper combination of specimen size, boundary condition, and fibre orientation was selected.

  • effect of blank holder force on strain evolution of forming of steel srpp fibre metal laminate
    The 8th Australasian Congress on Applied Mechanics 2014 (ACAM 8), 2014
    Co-Authors: Jae Nam, W.j. Cantwell, Adrian Lowe, Raj Das, Shankar Kalyanasundaram
    Abstract:

    Climate changes brought on by human interventions have proved to be more devastating than predicted during the recent decades. Recognition of seriousness of the situation has led regulatory organisations to impose strict targets on allowable carbon dioxide emissions from automotive vehicles. As a possible solution, it has been proposed that Fibre Metal Laminate (FML) system is used to reduce the weight of future vehicles. To facilitate this investigation, FML based on steel and Self-Reinforced Polypropylene was stamp formed into dome shapes under different blank holder forces (BHFs) at room temperature and its forming behaviour analysed. An open-die configuration was used in a hydraulic press so that a 3D photogrammetric measurement system (ARAMIS) could capture real-time surface strains. This paper presents findings on strain evolutions at different points along and at 45 to fibre directions of circular FML blank, through various stages of forming. It was found initiation and rate of deformation varied with distance from the pole, that the mode of deformations range from biaxial stretching at the pole to drawing towards flange region, at decreasing magnitudes away from the pole in general. More uniform strain distribution was observed for the FML compared to that of plain steel and the most significant effects of BHF were its influence on forming depth and level of strain reached before failure.

  • Experimental characterisation of the formability of a thermoplastic fibre metal laminate
    2012
    Co-Authors: Anthony Sexton, Wesley J. Cantwell, Matthew Doolan, Shankar Kalyanasundaram
    Abstract:

    This study aims to assess the forming behaviour of thermoplastic fibre metal laminates based on a Self-Reinforced Polypropylene composite and an aluminium alloy. The development of a method for the rapid manufacturing of parts made from fibre metal laminates would facilitate the widespread adoption of these materials in the automotive and renewable energy industries. Metallic parts are most commonly manufactured using the method of stamp forming and research into the application of this method to materials such as fibre metal laminates is gathering interest. In this investigation, specimens of varying geometry were stretched over a hemispherical punch and a noncontact optical measurement system was used to detail the stretch forming and analyse the effect of deformation mode on the formability of the laminate. The results from the experimentation were used to determine a forming limit diagram for the fibre metal laminate and to identify the safe forming limits of the material. In addition, the evolution of strain at two points of interest was observed to determine the deformation mode in each specimen and to determine the state of strain in the region of failure. These results were then compared with the forming of monolithic aluminium specimens. A significant finding of this work was that the FML showed superior formability than aluminium. This was shown primarily through the increased forming window elucidated by the forming limit curve for the FML and the more uniform meridian major strain distribution in the FML compared to the aluminium.

G Reyes - One of the best experts on this subject based on the ideXlab platform.

  • mechanical behavior of lightweight thermoplastic fiber metal laminates
    Journal of Materials Processing Technology, 2007
    Co-Authors: G Reyes, Hong Tae Kang
    Abstract:

    Abstract Lightweight thermoplastic-based fiber–metal laminates were developed based on Self-Reinforced Polypropylene and glass fiber-reinforced Polypropylene composite materials and an aluminum alloy 2024-T3. The laminates were manufactured using a fast one-step cold press manufacturing procedure. The mechanical behavior of the laminates was then investigated under tensile and fatigue loading conditions. The tensile properties of the plain aluminum, the composite materials and the thermoplastic fiber–metal laminates were investigated at quasi-static rates of loading. The fatigue tests were also conducted under load control in accordance with the ASTM E466 standard procedure. Various loading cycles were employed for the fatigue tests in order to minimize the possibility of heat generation on the composite materials. Load levels of 40, 60 and 80% of yield strength of each thermoplastic fiber–metal laminate panel were applied with zero to max loading. The glass fiber-reinforced Polypropylene hybrid systems exhibited higher fatigue strength than the Self-Reinforced Polypropylene-based fiber–metal laminates. Then, punch–stretch forming tests were performed in order to evaluate the formability of the hybrid systems. Experimental results revealed that the Self-Reinforced thermoplastic composite-based fiber–metal laminate exhibit excellent forming properties similar to that of the monolithic aluminum alloy of comparable thickness.

  • mechanical behavior of lightweight thermoplastic fiber metal laminates
    Journal of Materials Processing Technology, 2007
    Co-Authors: G Reyes, Hong Tae Kang
    Abstract:

    Abstract Lightweight thermoplastic-based fiber–metal laminates were developed based on Self-Reinforced Polypropylene and glass fiber-reinforced Polypropylene composite materials and an aluminum alloy 2024-T3. The laminates were manufactured using a fast one-step cold press manufacturing procedure. The mechanical behavior of the laminates was then investigated under tensile and fatigue loading conditions. The tensile properties of the plain aluminum, the composite materials and the thermoplastic fiber–metal laminates were investigated at quasi-static rates of loading. The fatigue tests were also conducted under load control in accordance with the ASTM E466 standard procedure. Various loading cycles were employed for the fatigue tests in order to minimize the possibility of heat generation on the composite materials. Load levels of 40, 60 and 80% of yield strength of each thermoplastic fiber–metal laminate panel were applied with zero to max loading. The glass fiber-reinforced Polypropylene hybrid systems exhibited higher fatigue strength than the Self-Reinforced Polypropylene-based fiber–metal laminates. Then, punch–stretch forming tests were performed in order to evaluate the formability of the hybrid systems. Experimental results revealed that the Self-Reinforced thermoplastic composite-based fiber–metal laminate exhibit excellent forming properties similar to that of the monolithic aluminum alloy of comparable thickness.

Ignaas Verpoest - One of the best experts on this subject based on the ideXlab platform.

  • identification and validation of a hyperelastic model for self reinforced Polypropylene draping
    International Journal of Material Forming, 2021
    Co-Authors: Marina Selezneva, Stepan Vladimirovitch Lomov, Naim Naouar, Yvan Denis, Larissa Gorbatikh, P J Hine, Yentl Swolfs, Ignaas Verpoest
    Abstract:

    Self-Reinforced Polypropylene (SRPP) is a composite in which the reinforcement and the matrix consist of the same polymer, namely Polypropylene. The present work focuses on the development and experimental validation of an FE model for thermoforming of SRPP. The constitutive model of SRPP sheet is based on the Boisse-Charmetant hyperelastic law. Material properties required to fit the model were obtained from the tensile and picture frame shear tests performed at forming temperatures and bending test of a non-consolidated fabric at room temperature. The model is validated in comparison with the experimental draping data, with special attention to parameters and patterns of wrinkles. Samples, preheated to a surface temperature of 170-175°C, were deformed up to 1-4 cm heights using a hemispherical mould with a 4.5 cm diameter. Overall, good qualitative correlation between experimental and modelling results is observed, which justifies use of the proposed model with the experimentally identified parameters for prediction of SRPP draping and subsequent analysis of the mechanical response of the consolidated part to loading.

  • introducing ductility in hybrid carbon fibre self reinforced composites through control of the damage mechanisms
    Composite Structures, 2015
    Co-Authors: Yentl Swolfs, P J Hine, Ignaas Verpoest, Yannick Meerten, I M Ward, Larissa Gorbatikh
    Abstract:

    Carbon fibre composites possess excellent mechanical properties, but suffer from brittleness. Hybridisation with Self-Reinforced Polypropylene (SRPP) is a promising strategy to introduce ductility into carbon fibre-reinforced Polypropylene (CFRPP). The present work demonstrates how different damage mechanisms in these hybrid composites change as a function of the carbon fibre volume fraction, the directionality of CFRPP and SRPP and their relative layer thickness. Multiple fractures of the CFRPP layers or “fragmentation” is achieved by optimising these parameters. This leads to a ductile hybrid composite with a gradual failure development.

  • tensile behaviour of intralayer hybrid composites of carbon fibre and self reinforced Polypropylene
    Composites Part A-applied Science and Manufacturing, 2014
    Co-Authors: Yentl Swolfs, Larissa Gorbatikh, P J Hine, I M Ward, Liesbet Crauwels, Eline Van Breda, Ignaas Verpoest
    Abstract:

    Abstract To improve the toughness of carbon fibre composites, unidirectional carbon fibre prepregs were hybridised with highly oriented Polypropylene (PP) tapes. The latter tapes are used in Self-Reinforced PP composites (SRPPs) with high toughness, but relatively low stiffness. The tensile behaviour of intralayer hybrids of oriented PP tapes and CFPP prepreg tapes was investigated by changing the layup and weave pattern, and by adding interleaved PP films. While stiffness and strength of these hybrids was decreased compared to CFPP, their ductility significantly increased by adding oriented PP tapes. The parallel behaviour of the two constituent materials was caused by delaminations, which developed after the CFPP failure and spreads over the entire sample. This behaviour was modelled and proven to be independent of layup and weave pattern. Interleaved films, which are often necessary for thermoformability, limited the delamination development by increasing the interlayer bonding and yielded a lower ultimate failure strain.

  • interply hybrid composites with carbon fiber reinforced Polypropylene and self reinforced Polypropylene
    Composites Part A-applied Science and Manufacturing, 2010
    Co-Authors: Ichiro Taketa, Stepan Vladimirovitch Lomov, Larissa Gorbatikh, Jon Ustarroz, Ignaas Verpoest
    Abstract:

    Abstract The focus of the present study is on hybrid composites with interplied carbon fiber reinforced Polypropylene (CFRPP) between Self-Reinforced Polypropylene (SRPP) layers. SRPP is produced by hot compaction of a woven fabric of highly oriented Polypropylene and has an intrinsic behavior of shrinkage under high temperatures. The aim of this research is to enhance the tensile properties of the CFRPP/SRPP hybrid composites by using the SRPP shrinkage to introduce a compressive pre-strain in CFRPP. The results from tensile testing show that the failure strain of the hybrid composites is improved in comparison with CFRPP. The modulus and strength are noted to be lower than the ones expected from the rule of mixture. This may be attributed to the introduction of local misalignment (waviness) of carbon fibers caused by the SRPP shrinkage during consolidation.