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Wei Tan - One of the best experts on this subject based on the ideXlab platform.

  • experimental and numerical studies on the impact response of damage tolerant hybrid unidirectional woven carbon fibre reinforced Composite laminates
    Composites Part B-engineering, 2018
    Co-Authors: Haibao Liu, Brian Falzon, Wei Tan
    Abstract:

    Abstract A woven five-harness satin (5HS) weave with AS4 carbon fibres, and unidirectional high strength IMS60 carbon fibres were used to manufacture hybrid laminates, using resin infusion, to assess their performance in low velocity impact tests. Load/energy-time curves and load-displacement curves were extracted from the experimental data, and non-destructive C-scanning was performed on all pre- and post-impacted specimens to quantify the extent of damage incurred. A finite element-based computational damage model was developed to predict the material response of these hybrid unidirectional/woven laminates. The intralaminar damage model formulation, by necessity, consists of two sub-models, a unidirectional constitutive model and a woven constitutive model. The built-in surface-based cohesive behaviour in Abaqus/Explicit was used to define the interlaminar damage model for capturing delamination. The reliability of this model was validated using in-house experimental data obtained from standard drop-weight impact tests. The simulated reaction-force and absorbed energy showed excellent agreement with experiment results. The post-impact delamination and permanent indentation deformation were also accurately captured. The accuracy of the damage model facilitated a quantitative comparison between the performance of a hybrid unidirectional/woven (U/W) laminates and a pure unidirectional (PU) carbon-fibre reinforced Composite laminates of equivalent lay-up. The hybrid laminates were shown to yield better impact resistance.

  • predicting the compression after impact cai strength of damage tolerant hybrid unidirectional woven carbon fibre reinforced Composite laminates
    Composites Part A-applied Science and Manufacturing, 2018
    Co-Authors: Haibao Liu, Brian Falzon, Wei Tan
    Abstract:

    Abstract The evaluation of Compression-After-Impact (CAI) strength is of great significance in the design of Composite aerostructures. This paper presents a model for the numerical simulation of Compression-After-Impact (CAI) of hybrid unidirectional (UD)/woven carbon-fibre reinforced Composite laminates. This three-dimensional damage model is based on Continuum Damage Mechanics (CDM) and Linear Elastic Fracture Mechanics (LEFM), implemented as a user defined material subroutine (VUMAT) in Abaqus/Explicit. This model, which accounts for interlaminar and intralaminar damage, and load reversal, incorporates a non-linear shear profile to account for matrix plasticity. Two different Composite laminate lay-ups with varying extent of initial impact damage were tested to validate the computational model and enable a quantitative study of the influence of using woven plies on the surfaces of a laminate. Woven surface plies are often used in Composite aerostructures to mitigate damage during drilling and constrain the extent of damage during low velocity impact. Good correlation was obtained between physical testing and simulation results, which establishes the capability of this damage model in predicting the structural response of Composite laminates. The fully validated model was used to compare the CAI strength of an equivalent UD-only carbon-fibre reinforced Composite laminate. The results showed that the hybrid unidirectional (UD)/woven laminate had a marginally higher strength (+3.3%) than the equivalent unidirectional (UD)-only laminate.

Brian Falzon - One of the best experts on this subject based on the ideXlab platform.

  • An experimental and numerical study on the crush behaviour of hybrid unidirectional/woven carbon-fibre reinforced Composite laminates
    International Journal of Mechanical Sciences, 2019
    Co-Authors: Brian Falzon, John P. Dear
    Abstract:

    Abstract In Composite aircraft structures, woven carbon-fibre reinforced plies are often used as the surface plies of a monolithic Composite panel, made from unidirectional plies, to mitigate damage during drilling and provide a measure of impact damage resistance. This research presents, for the first time, a detailed experimental and numerical study on the crush behaviour of hybrid unidirectional/woven carbon-fibre reinforced Composite laminates. Quasi-static crush tests are performed on Composite specimens with two different trigger geometries; a bevel-trigger and a steeple-trigger. A computational model, which accounts for both interlaminar and intralaminar damage in hybrid unidirectional (UD)/woven Composite laminates, implemented as a user subroutine in Abaqus/Explicit, was used. A comparison between experimental and numerical results confirms the computational tool's accuracy in predicting the energy absorption and damage mechanisms of hybrid specimens. The proposed approach could significantly reduce the extent of physical testing required in the development of crashworthy structures.

  • experimental and numerical studies on the impact response of damage tolerant hybrid unidirectional woven carbon fibre reinforced Composite laminates
    Composites Part B-engineering, 2018
    Co-Authors: Haibao Liu, Brian Falzon, Wei Tan
    Abstract:

    Abstract A woven five-harness satin (5HS) weave with AS4 carbon fibres, and unidirectional high strength IMS60 carbon fibres were used to manufacture hybrid laminates, using resin infusion, to assess their performance in low velocity impact tests. Load/energy-time curves and load-displacement curves were extracted from the experimental data, and non-destructive C-scanning was performed on all pre- and post-impacted specimens to quantify the extent of damage incurred. A finite element-based computational damage model was developed to predict the material response of these hybrid unidirectional/woven laminates. The intralaminar damage model formulation, by necessity, consists of two sub-models, a unidirectional constitutive model and a woven constitutive model. The built-in surface-based cohesive behaviour in Abaqus/Explicit was used to define the interlaminar damage model for capturing delamination. The reliability of this model was validated using in-house experimental data obtained from standard drop-weight impact tests. The simulated reaction-force and absorbed energy showed excellent agreement with experiment results. The post-impact delamination and permanent indentation deformation were also accurately captured. The accuracy of the damage model facilitated a quantitative comparison between the performance of a hybrid unidirectional/woven (U/W) laminates and a pure unidirectional (PU) carbon-fibre reinforced Composite laminates of equivalent lay-up. The hybrid laminates were shown to yield better impact resistance.

  • predicting the compression after impact cai strength of damage tolerant hybrid unidirectional woven carbon fibre reinforced Composite laminates
    Composites Part A-applied Science and Manufacturing, 2018
    Co-Authors: Haibao Liu, Brian Falzon, Wei Tan
    Abstract:

    Abstract The evaluation of Compression-After-Impact (CAI) strength is of great significance in the design of Composite aerostructures. This paper presents a model for the numerical simulation of Compression-After-Impact (CAI) of hybrid unidirectional (UD)/woven carbon-fibre reinforced Composite laminates. This three-dimensional damage model is based on Continuum Damage Mechanics (CDM) and Linear Elastic Fracture Mechanics (LEFM), implemented as a user defined material subroutine (VUMAT) in Abaqus/Explicit. This model, which accounts for interlaminar and intralaminar damage, and load reversal, incorporates a non-linear shear profile to account for matrix plasticity. Two different Composite laminate lay-ups with varying extent of initial impact damage were tested to validate the computational model and enable a quantitative study of the influence of using woven plies on the surfaces of a laminate. Woven surface plies are often used in Composite aerostructures to mitigate damage during drilling and constrain the extent of damage during low velocity impact. Good correlation was obtained between physical testing and simulation results, which establishes the capability of this damage model in predicting the structural response of Composite laminates. The fully validated model was used to compare the CAI strength of an equivalent UD-only carbon-fibre reinforced Composite laminate. The results showed that the hybrid unidirectional (UD)/woven laminate had a marginally higher strength (+3.3%) than the equivalent unidirectional (UD)-only laminate.

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

  • experimental and numerical studies on the impact response of damage tolerant hybrid unidirectional woven carbon fibre reinforced Composite laminates
    Composites Part B-engineering, 2018
    Co-Authors: Haibao Liu, Brian Falzon, Wei Tan
    Abstract:

    Abstract A woven five-harness satin (5HS) weave with AS4 carbon fibres, and unidirectional high strength IMS60 carbon fibres were used to manufacture hybrid laminates, using resin infusion, to assess their performance in low velocity impact tests. Load/energy-time curves and load-displacement curves were extracted from the experimental data, and non-destructive C-scanning was performed on all pre- and post-impacted specimens to quantify the extent of damage incurred. A finite element-based computational damage model was developed to predict the material response of these hybrid unidirectional/woven laminates. The intralaminar damage model formulation, by necessity, consists of two sub-models, a unidirectional constitutive model and a woven constitutive model. The built-in surface-based cohesive behaviour in Abaqus/Explicit was used to define the interlaminar damage model for capturing delamination. The reliability of this model was validated using in-house experimental data obtained from standard drop-weight impact tests. The simulated reaction-force and absorbed energy showed excellent agreement with experiment results. The post-impact delamination and permanent indentation deformation were also accurately captured. The accuracy of the damage model facilitated a quantitative comparison between the performance of a hybrid unidirectional/woven (U/W) laminates and a pure unidirectional (PU) carbon-fibre reinforced Composite laminates of equivalent lay-up. The hybrid laminates were shown to yield better impact resistance.

  • predicting the compression after impact cai strength of damage tolerant hybrid unidirectional woven carbon fibre reinforced Composite laminates
    Composites Part A-applied Science and Manufacturing, 2018
    Co-Authors: Haibao Liu, Brian Falzon, Wei Tan
    Abstract:

    Abstract The evaluation of Compression-After-Impact (CAI) strength is of great significance in the design of Composite aerostructures. This paper presents a model for the numerical simulation of Compression-After-Impact (CAI) of hybrid unidirectional (UD)/woven carbon-fibre reinforced Composite laminates. This three-dimensional damage model is based on Continuum Damage Mechanics (CDM) and Linear Elastic Fracture Mechanics (LEFM), implemented as a user defined material subroutine (VUMAT) in Abaqus/Explicit. This model, which accounts for interlaminar and intralaminar damage, and load reversal, incorporates a non-linear shear profile to account for matrix plasticity. Two different Composite laminate lay-ups with varying extent of initial impact damage were tested to validate the computational model and enable a quantitative study of the influence of using woven plies on the surfaces of a laminate. Woven surface plies are often used in Composite aerostructures to mitigate damage during drilling and constrain the extent of damage during low velocity impact. Good correlation was obtained between physical testing and simulation results, which establishes the capability of this damage model in predicting the structural response of Composite laminates. The fully validated model was used to compare the CAI strength of an equivalent UD-only carbon-fibre reinforced Composite laminate. The results showed that the hybrid unidirectional (UD)/woven laminate had a marginally higher strength (+3.3%) than the equivalent unidirectional (UD)-only laminate.

John P. Dear - One of the best experts on this subject based on the ideXlab platform.

  • An experimental and numerical study on the crush behaviour of hybrid unidirectional/woven carbon-fibre reinforced Composite laminates
    International Journal of Mechanical Sciences, 2019
    Co-Authors: Brian Falzon, John P. Dear
    Abstract:

    Abstract In Composite aircraft structures, woven carbon-fibre reinforced plies are often used as the surface plies of a monolithic Composite panel, made from unidirectional plies, to mitigate damage during drilling and provide a measure of impact damage resistance. This research presents, for the first time, a detailed experimental and numerical study on the crush behaviour of hybrid unidirectional/woven carbon-fibre reinforced Composite laminates. Quasi-static crush tests are performed on Composite specimens with two different trigger geometries; a bevel-trigger and a steeple-trigger. A computational model, which accounts for both interlaminar and intralaminar damage in hybrid unidirectional (UD)/woven Composite laminates, implemented as a user subroutine in Abaqus/Explicit, was used. A comparison between experimental and numerical results confirms the computational tool's accuracy in predicting the energy absorption and damage mechanisms of hybrid specimens. The proposed approach could significantly reduce the extent of physical testing required in the development of crashworthy structures.

Ozcan Mutlu - One of the best experts on this subject based on the ideXlab platform.

  • Clinical survival of indirect, anterior 3-unit surface-retained Fibre-Reinforced Composite fixed dental prosthesis: Up to 7.5-years follow-up
    'Elsevier BV', 2015
    Co-Authors: Kumbuloglu Ovul, Ozcan Mutlu
    Abstract:

    WOS: 000354873400005PubMed ID: 25913141Objectives: This prospective clinical study evaluated the performance of indirect, anterior, surface-retained, Fibre-Reinforced-Composite restorations (ISFRCR). Methods: Between June-2003 and January-2011, a total of 134 patients (83 females, 51 males, 16-68 years old) received 175 ISFRCRs (local ethical registration number: 14/9/4). All restorations were made indirectly on a plaster model using unidirectional E-glass fibres (everStick C&B, StickTech) in combination with a laboratory resin Composite (Dialogue, Schutz Dental) and cemented according to the instructions of 4 resin cements [(RelyX ARC, 3M-ESPE, n = 61), Bifix DC, VOCO, n = 45), Variolink II (Ivoclar Vivadent, n = 32) and Multilink (Ivoclar Vivadent, n = 37)]. After baseline recordings, patients were followed at 6 months and thereafter annually up to 7.5 years. The evaluation protocol involved technical (chipping, debonding or fracture of tooth/restoration) and biological failures (caries). Results: Mean observation period was 58 months. Altogether, 13 failures were observed [survival rate: 97.7%] (Kaplan-Meier). One catastrophic fracture [(cement: RelyX ARC), eight partial debonding (cement: Bifix DC (5), Multilink (1), RelyX ARC (1), Variolink II (1)] and four delaminations of veneering Composite [(cement: Bifix DC (2), RelyX ARC (1), Multilink (1)] were observed. Except one replacement, all defective restorations were repaired or recemented. Annual failure rate of ISFRCRs was 1.73%. The survival rates with the four resin cements did not show significant differences (RelyX ARC: 98.3%; Bifix DC: 93.5%; Variolink 2: 100%; Multilink: 100%) (p = 0.114). Secondary caries did not occur in any of the teeth. Conclusion: The 3-unit anterior indirect surface-retained resin-bonded FRC FDPs showed similar clinical survival rate when cemented with the resin cements tested. Experienced failures in general were due to debonding of the restoration or delamination of the veneering Composite. Clinical significance: 3-unit surface retained resin-bonded FRCFDPs could be considered minimal invasive and cost-effective alternatives to conventional tooth-or implant-borne FDPs. Failures were mainly repairable in the form of chipping or debonding depending on the resin cement type. (C) 2015 Elsevier Ltd. All rights reserved

  • Clinical survival of indirect, anterior 3-unit surface-retained Fibre-Reinforced Composite fixed dental prosthesis: Up to 7.5-years follow-up
    'Elsevier BV', 2015
    Co-Authors: Kumbuloglu Ovul, Ozcan Mutlu
    Abstract:

    OBJECTIVES This prospective clinical study evaluated the performance of indirect, anterior, surface-retained, Fibre-Reinforced-Composite restorations (ISFRCR). METHODS Between June-2003 and January-2011, a total of 134 patients (83 females, 51 males, 16-68 years old) received 175 ISFRCRs (local ethical registration number: 14/9/4). All restorations were made indirectly on a plaster model using unidirectional E-glass fibres (everStick C&B, StickTech) in combination with a laboratory resin Composite (Dialogue, Schütz Dental) and cemented according to the instructions of 4 resin cements [(RelyX ARC, 3M-ESPE, n=61), Bifix DC, VOCO, n=45), Variolink II (Ivoclar Vivadent, n=32) and Multilink (Ivoclar Vivadent, n=37)]. After baseline recordings, patients were followed at 6 months and thereafter annually up to 7.5 years. The evaluation protocol involved technical (chipping, debonding or fracture of tooth/restoration) and biological failures (caries). RESULTS Mean observation period was 58 months. Altogether, 13 failures were observed [survival rate: 97.7%] (Kaplan-Meier). One catastrophic fracture [(cement: RelyX ARC), eight partial debonding (cement: Bifix DC (5), Multilink (1), RelyX ARC (1), Variolink II (1)] and four delaminations of veneering Composite [(cement: Bifix DC (2), RelyX ARC (1), Multilink (1)] were observed. Except one replacement, all defective restorations were repaired or recemented. Annual failure rate of ISFRCRs was 1.73%. The survival rates with the four resin cements did not show significant differences (RelyX ARC: 98.3%; Bifix DC: 93.5%; Variolink 2: 100%; Multilink: 100%) (p=0.114). Secondary caries did not occur in any of the teeth. CONCLUSION The 3-unit anterior indirect surface-retained resin-bonded FRC FDPs showed similar clinical survival rate when cemented with the resin cements tested. Experienced failures in general were due to debonding of the restoration or delamination of the veneering Composite. CLINICAL SIGNIFICANCE 3-unit surface retained resin-bonded FRC FDPs could be considered minimal invasive and cost-effective alternatives to conventional tooth- or implant-borne FDPs. Failures were mainly repairable in the form of chipping or debonding depending on the resin cement type