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Dr LEE HARPER's Outputs (53)

Optimisation of intra-ply stitch removal for improved formability of biaxial non-crimp fabrics (2021)
Journal Article
Chen, S., Joesbury, A. M., Yu, F., Harper, L. T., & Warrior, N. A. (2022). Optimisation of intra-ply stitch removal for improved formability of biaxial non-crimp fabrics. Composites Part B: Engineering, 229, Article 109464. https://doi.org/10.1016/j.compositesb.2021.109464

Automated fabric forming solutions are required to meet the demand of liquid moulding processes, but wrinkling is a common problem for double-curvature parts due to a combination of the reinforcement type, manufacturing parameters and the part geomet... Read More about Optimisation of intra-ply stitch removal for improved formability of biaxial non-crimp fabrics.

Investigation into the effects of inter-ply sliding during double diaphragm forming for multi-layered biaxial non-crimp fabrics (2021)
Journal Article
Yu, F., Chen, S., Harper, L. T., & Warrior, N. A. (2021). Investigation into the effects of inter-ply sliding during double diaphragm forming for multi-layered biaxial non-crimp fabrics. Composites Part A: Applied Science and Manufacturing, 150, Article 106611. https://doi.org/10.1016/j.compositesa.2021.106611

The effect of inter-ply sliding was investigated for multi-ply Non-Crimp Fabric (NCF) preforms during the Double Diaphragm Forming (DDF) process. A Finite Element (FE) model was employed to investigate the influence of the ply layup sequence and the... Read More about Investigation into the effects of inter-ply sliding during double diaphragm forming for multi-layered biaxial non-crimp fabrics.

Double diaphragm forming simulation using a global-to-local modelling strategy for detailed defect detection in large structures (2021)
Journal Article
Yu, F., Chen, S., Harper, L., & Warrior, N. (2021). Double diaphragm forming simulation using a global-to-local modelling strategy for detailed defect detection in large structures. Composites Part A: Applied Science and Manufacturing, 147, Article 106457. https://doi.org/10.1016/j.compositesa.2021.106457

A global-to-local modelling strategy is presented based on a sub-modelling approach to predict the formation of macroscale defects in bi-axial non-crimp fabric (NCF) during double diaphragm forming (DDF). A full-scale global simulation is initially p... Read More about Double diaphragm forming simulation using a global-to-local modelling strategy for detailed defect detection in large structures.

Simulating the effect of fabric bending stiffness on the wrinkling behaviour of biaxial fabrics during preforming (2021)
Journal Article
Yu, F., Chen, S., Harper, L., & Warrior, N. (2021). Simulating the effect of fabric bending stiffness on the wrinkling behaviour of biaxial fabrics during preforming. Composites Part A: Applied Science and Manufacturing, 143, Article 106308. https://doi.org/10.1016/j.compositesa.2021.106308

A macroscopic finite element model has been established to investigate the forming-induced wrinkling behaviour for bi-axial fabrics. Results indicate that using a linear bending model with a constant bending stiffness produces unrealistic wrinkle pat... Read More about Simulating the effect of fabric bending stiffness on the wrinkling behaviour of biaxial fabrics during preforming.

Solid epoxy resin systems for automated composite manufacturing (2020)
Journal Article
Yousefi, N., Evans, A. D., Harper, L. T., Maples, H. A., James, T., & Bismarck, A. (2021). Solid epoxy resin systems for automated composite manufacturing. Composites Part A: Applied Science and Manufacturing, 142, Article 106205. https://doi.org/10.1016/j.compositesa.2020.106205

© 2020 The Author(s) Thermosetting resins were formulated by mixing solid epoxy components, hardener and accelerator at elevated temperature. These mixtures were ground into uncured, solid resin powders and dispensed onto carbon fibres using a powder... Read More about Solid epoxy resin systems for automated composite manufacturing.

The behaviour of thermoplastic and thermoset carbon-fibre composites subjected to low-velocity and high-velocity impact (2020)
Journal Article
Liu, H., Liu, J., Ding, Y., Zheng, J., Kong, X., Zhou, J., Harper, L., Blackman, B. R. K., Kinloch, A. J., & Dear, J. P. (2020). The behaviour of thermoplastic and thermoset carbon-fibre composites subjected to low-velocity and high-velocity impact. Journal of Materials Science, 55, 15741–15768. https://doi.org/10.1007/s10853-020-05133-0

The present paper describes the results from experimental and theoretical modelling studies on the behaviour of continuous carbon-fibre/polymer matrix composites subjected to a relatively low-velocity or high-velocity impact, using a rigid, metallic... Read More about The behaviour of thermoplastic and thermoset carbon-fibre composites subjected to low-velocity and high-velocity impact.

A macroscale finite element approach for simulating the bending behaviour of biaxial fabrics (2020)
Journal Article
Yu, F., Chen, S., Viisainen, J., Sutcliffe, M., Harper, L., & Warrior, N. (2020). A macroscale finite element approach for simulating the bending behaviour of biaxial fabrics. Composites Science and Technology, 191, Article 108078. https://doi.org/10.1016/j.compscitech.2020.108078

A macroscale finite element (FE) model was developed to simulate the forming behaviour of biaxial fabrics, incorporating the effects of bending stiffness to predict fabric wrinkling. The dependency of the bending stiffness on the fibre orientation wa... Read More about A macroscale finite element approach for simulating the bending behaviour of biaxial fabrics.

Modelling the permeability of random discontinuous carbon fibre preforms (2020)
Journal Article
Xiao, Z., Liu, X., Harper, L. T., Endruweit, A., & Warrior, N. A. (2020). Modelling the permeability of random discontinuous carbon fibre preforms. Journal of Composite Materials, 54(20), 2739-2751. https://doi.org/10.1177/0021998320902506

A force-directed algorithm was developed to create representative geometrical models of fibre distributions in Directed Carbon Fibre Preforms (DCFP). Local permeability values were calculated for the preform models depending on the local fibre orient... Read More about Modelling the permeability of random discontinuous carbon fibre preforms.

Simulation of the forming process for curved composite sandwich panels (2019)
Journal Article
Chen, S., McGregor, O. L., Endruweit, A., Harper, L. T., & Warrior, N. A. (2020). Simulation of the forming process for curved composite sandwich panels. International Journal of Material Forming, 13, 967–980. https://doi.org/10.1007/s12289-019-01520-4

© 2019, The Author(s). For affordable high-volume manufacture of sandwich panels with complex curvature and varying thickness, fabric skins and a core structure are simultaneously press-formed using a set of matched tools. A finite-element-based proc... Read More about Simulation of the forming process for curved composite sandwich panels.

Optimisation of local in-plane constraining forces in double diaphragm forming (2018)
Journal Article
Chen, S., McGregor, O. P., Harper, L. T., Endruweit, A., & Warrior, N. A. (2018). Optimisation of local in-plane constraining forces in double diaphragm forming. Composite Structures, 201, 570-581. https://doi.org/10.1016/j.compstruct.2018.06.062

© 2018 Elsevier Ltd Rigid blocks (risers) were introduced in the double diaphragm forming (DDF) process to change the local in-plane strain distribution in the diaphragms, aimed at reducing wrinkling defects in the production of fabric preforms. A tw... Read More about Optimisation of local in-plane constraining forces in double diaphragm forming.

Simulating damage onset and evolution in fully bio-resorbable composite under three-point bending (2018)
Journal Article
Gao, X., Chen, M., Yang, X., Harper, L., Ahmed, I., & Lu, J. (2018). Simulating damage onset and evolution in fully bio-resorbable composite under three-point bending. Journal of the Mechanical Behavior of Biomedical Materials, 81, https://doi.org/10.1016/j.jmbbm.2018.02.022

This paper presents a strain-based damage model to predict the stress-strain relationship and investigate the damage onset and evolution of the fibre and matrix of a fully bio-resorbable phosphate glass fibre reinforced composite under three-point be... Read More about Simulating damage onset and evolution in fully bio-resorbable composite under three-point bending.

Finite element study of the microdroplet test for interfacial shear strength: Effects of geometric parameters for a carbon fibre/epoxy system (2017)
Journal Article
Zhao, Q., Qian, C., Harper, L., & Warrior, N. (2018). Finite element study of the microdroplet test for interfacial shear strength: Effects of geometric parameters for a carbon fibre/epoxy system. Journal of Composite Materials, 52(16), 2163-2177. https://doi.org/10.1177/0021998317740943

A 3D finite element model has been developed to identify the main causes of variability in the microdroplet test, which is commonly used to characterise the interfacial shear strength between polymer matrices and single filaments. A more realistic dr... Read More about Finite element study of the microdroplet test for interfacial shear strength: Effects of geometric parameters for a carbon fibre/epoxy system.

A water-soluble core material for manufacturing hollow composite sections (2017)
Journal Article
Xiao, Z., Harper, L., Kennedy, A. R., & Warrior, N. (2017). A water-soluble core material for manufacturing hollow composite sections. Composite Structures, 182, https://doi.org/10.1016/j.compstruct.2017.09.058

This paper presents the development of a low-cost water-soluble core material, which is suitable for producing hollow composite structures via high pressure moulding processes, such as compression moulding and resin transfer moulding. The bulk materi... Read More about A water-soluble core material for manufacturing hollow composite sections.

Long discontinuous carbon fibre/polypropylene composites for high volume structural applications (2017)
Journal Article
Harper, L., Burn, D., Johnson, M. S., & Warrior, N. (in press). Long discontinuous carbon fibre/polypropylene composites for high volume structural applications. Journal of Composite Materials, https://doi.org/10.1177/0021998317722204

A processing route is presented to manufacture discontinuous carbon fibre reinforced polypropylene (CF.PP) composites, using much longer fibre lengths (25mm) and higher volume fractions (up to 45%) than previously reported in the literature. Carbon f... Read More about Long discontinuous carbon fibre/polypropylene composites for high volume structural applications.

Double diaphragm forming simulation for complex composite structures (2017)
Journal Article
Chen, S., McGregor, O., Endruweit, A., Elsmore, M., De Focatiis, D., Harper, L., & Warrior, N. (2017). Double diaphragm forming simulation for complex composite structures. Composites Part A: Applied Science and Manufacturing, 95, 346-358. https://doi.org/10.1016/j.compositesa.2017.01.017

A finite element (FE) model has been developed to simulate the double diaphragm forming (DDF) process, to identify potential defects when forming complex 3D preforms from 2D biaxial non-crimp fabric plies. Three different metrics have been introduced... Read More about Double diaphragm forming simulation for complex composite structures.

Compression moulding of composites with hybrid fibre architectures (2016)
Journal Article
Corbridge, D., Harper, L. T., De Focatiis, D. S., & Warrior, N. (2017). Compression moulding of composites with hybrid fibre architectures. Composites Part A: Applied Science and Manufacturing, 95, 87-99. https://doi.org/10.1016/j.compositesa.2016.12.018

Advanced Sheet Moulding Compounds (ASMC) and unidirectional (UD) prepregs have been co-compression moulded to form a hybrid composite material. In-mould flow influences the UD fibre architecture in two ways. When UD fibres are aligned transversely to... Read More about Compression moulding of composites with hybrid fibre architectures.

3D geometric modelling of discontinuous fibre composites using a force-directed algorithm (2016)
Journal Article
Harper, L., Qian, C., Luchoo, R., & Warrior, N. (2017). 3D geometric modelling of discontinuous fibre composites using a force-directed algorithm. Journal of Composite Materials, 51(17), 2389-2406. https://doi.org/10.1177/0021998316672722

A geometrical modelling scheme is presented to produce representative architectures for discontinuous fibre composites, enabling downstream modelling of mechanical properties. The model generates realistic random fibre architectures containing high f... Read More about 3D geometric modelling of discontinuous fibre composites using a force-directed algorithm.

Defect formation during preforming of a bi-axial non-crimp fabric with a pillar stitch pattern (2016)
Journal Article
Chen, S., McGregor, O., Harper, L., Endruweit, A., & Warrior, N. (2016). Defect formation during preforming of a bi-axial non-crimp fabric with a pillar stitch pattern. Composites Part A: Applied Science and Manufacturing, 91, 156-167. https://doi.org/10.1016/j.compositesa.2016.09.016

To capture the asymmetrical shear behaviour of a bi-axial NCF with a pillar stitch, a non-orthogonal constitutive model was developed and implemented in finite element forming simulations. Preforming experiments indicate that the local distribution o... Read More about Defect formation during preforming of a bi-axial non-crimp fabric with a pillar stitch pattern.

Flow characteristics of carbon fibre moulding compounds (2016)
Journal Article
Evans, A., Qian, C., Turner, T., Harper, L., & Warrior, N. (2016). Flow characteristics of carbon fibre moulding compounds. Composites Part A: Applied Science and Manufacturing, 90, 1-12. https://doi.org/10.1016/j.compositesa.2016.06.020

This paper presents the development of a low-cost carbon fibre moulding compound using an automated spray deposition process. Directed Fibre Compounding (DFC) is used to produce charge packs directly from low cost carbon fibre tows and liquid epoxy r... Read More about Flow characteristics of carbon fibre moulding compounds.

Optimisation of composite bone plates for ulnar transverse fractures (2016)
Journal Article
Chakladar, N. D., Harper, L. T., & Parsons, A. J. (2016). Optimisation of composite bone plates for ulnar transverse fractures. Journal of the Mechanical Behavior of Biomedical Materials, 57, https://doi.org/10.1016/j.jmbbm.2016.01.029

Metallic bone plates are commonly used for arm bone fractures where conservative treatment (casts) cannot provide adequate support and compression at the fracture site. These plates, made of stainless steel or titanium alloys, tend to shield stress t... Read More about Optimisation of composite bone plates for ulnar transverse fractures.