Dr LEE HARPER's Outputs (54)

The Impact and Compression-After-Impact Behaviour of CFRP After Double Impacts in Different Locations (2025)
Journal Article
Brooks, R. A., Liu, J., Joesbury, A., Harper, L., Liu, H., Blackman, B. R., Kinloch, A. J., & Dear, J. P. (2025). The Impact and Compression-After-Impact Behaviour of CFRP After Double Impacts in Different Locations. Strain, 61(2), Article e70006. https://doi.org/10.1111/str.70006

The present paper investigates the low-velocity impact behaviour and the compression-after-impact (CAI) behaviour of carbon-fibre reinforced-plastic (CFRP) composite panels after two impacts in different locations on a test coupon. The effect of chan... Read More about The Impact and Compression-After-Impact Behaviour of CFRP After Double Impacts in Different Locations.

Joule heating of carbon fibre tapes – A low-cost approach for automated dry fibre deposition (2024)
Journal Article
Lu, S., Song, P., Harper, L., & Turner, T. (2024). Joule heating of carbon fibre tapes – A low-cost approach for automated dry fibre deposition. Composites Part A: Applied Science and Manufacturing, 187, Article 108498. https://doi.org/10.1016/j.compositesa.2024.108498

Joule heating is potentially a low-cost option for activating the binder on the surface of carbon fibre tapes during automated dry fibre placement (ADFP). In this paper, the electrical contact resistance between a carbon fibre tape and cylindrical el... Read More about Joule heating of carbon fibre tapes – A low-cost approach for automated dry fibre deposition.

Poly-Ether-Ether-Ketone (PEEK) Biomaterials and Composites: Challenges, Progress, and Opportunities (2024)
Journal Article
Molinar-Díaz, J., Parsons, A. J., Ahmed, I., Warrior, N. A., & Harper, L. T. (2024). Poly-Ether-Ether-Ketone (PEEK) Biomaterials and Composites: Challenges, Progress, and Opportunities. Polymer Reviews, 1-39. https://doi.org/10.1080/15583724.2024.2406965

Polyetheretherketone (PEEK) is a lightweight, bioinert, high-performance thermoplastic that is beginning to see clinical use in orthopedic applications. PEEK outperforms conventional metallic counterparts in terms of reduced stress shielding and impr... Read More about Poly-Ether-Ether-Ketone (PEEK) Biomaterials and Composites: Challenges, Progress, and Opportunities.

Laser cutting of CFRP using novel cutting strategies (2024)
Journal Article
Kelsey, D., Elkington, H., Jackson-Crisp, A., Harper, L., Marithmu, S., & Voisey, K. (2024). Laser cutting of CFRP using novel cutting strategies. Procedia CIRP, 124, 509-512. https://doi.org/10.1016/j.procir.2024.08.163

Laser cutting of carbon fibre reinforced plastics generates a heat affected zone (HAZ) in the vicinity of the cut, affecting the integrity of the material and therefore the uptake of laser cutting for composite applications. This w... Read More about Laser cutting of CFRP using novel cutting strategies.

An analytical model for wrinkle-free forming of composite laminates (2024)
Journal Article
Trenam, A., Aza, C., Jones, C., Lawrence, G., Harper, L., Rhead, A., Loukaides, E. G., & Butler, R. (2024). An analytical model for wrinkle-free forming of composite laminates. Composites Part A: Applied Science and Manufacturing, 186, Article 108386. https://doi.org/10.1016/j.compositesa.2024.108386

Double Diaphragm Forming (DDF) of 3D shapes significantly increases production rates for laminated composite parts when compared with Automated Fibre Placement. However, it is prone to the occurrence of wrinkling defects, which can lead either to con... Read More about An analytical model for wrinkle-free forming of composite laminates.

Characterisation of process-induced variability in wrinkle defects during double diaphragm forming of non-crimp fabric (2024)
Journal Article
Codolini, A., Chen, S., Lawrence, G., Harper, L., & Sutcliffe, M. (2024). Characterisation of process-induced variability in wrinkle defects during double diaphragm forming of non-crimp fabric. Composites Part B: Engineering, 281, Article 111549. https://doi.org/10.1016/j.compositesb.2024.111549

Experiments and numerical simulations are employed to determine the critical process variables that affect the quality of a two-layer biaxial non-crimp fabric (NCF) preformed using the double diaphragm forming (DDF) process. To prevent wrinkling defe... Read More about Characterisation of process-induced variability in wrinkle defects during double diaphragm forming of non-crimp fabric.

The Relationship Between the Extent of Indentation and Impact Damage in Carbon-Fibre Reinforced-Plastic Composites after a Low-Velocity Impact (2024)
Journal Article
Brooks, R. A., Liu, J., Hall, Z. E., Joesbury, A. M., Harper, L. T., Liu, H., Kinloch, A. J., & Dear, J. P. (2024). The Relationship Between the Extent of Indentation and Impact Damage in Carbon-Fibre Reinforced-Plastic Composites after a Low-Velocity Impact. Applied Composite Materials, 31, 1869-1888. https://doi.org/10.1007/s10443-024-10223-2

The present paper investigates the low-velocity impact behaviour of carbon-fibre reinforced-plastic (CFRP) composite panels and the damage incurred when they are subjected to a single impact. The relationship between the depth of permanent surface in... Read More about The Relationship Between the Extent of Indentation and Impact Damage in Carbon-Fibre Reinforced-Plastic Composites after a Low-Velocity Impact.

Thermoplastic composite injection-overmoulding with indirectly-loaded reinforcement: Design for manufacture (2024)
Journal Article
Parsons, A. J., Chen, S., Ryder, A., Bradley, D., Warrior, N. A., & Harper, L. T. (2024). Thermoplastic composite injection-overmoulding with indirectly-loaded reinforcement: Design for manufacture. Composite Structures, 337, Article 118056. https://doi.org/10.1016/j.compstruct.2024.118056

Thermoplastic Overmoulding is an emerging manufacturing method combining low-cost, high-rate injection moulding with continuous fibre composite elements. The combination of materials with dissimilar stiffnesses can create stress concentrations and wa... Read More about Thermoplastic composite injection-overmoulding with indirectly-loaded reinforcement: Design for manufacture.

Design and Manufacture of Structural Composites (2023)
Book
Harper, L., & Clifford, M. (Eds.). (2023). Design and Manufacture of Structural Composites. Elsevier. https://doi.org/10.1016/c2018-0-05165-8

Design and Manufacture of Structural Composites provides an overview of the main manufacturing challenges encountered when processing fibre-reinforced composite materials. Composites are unique in that the material is created at the same time as the... Read More about Design and Manufacture of Structural Composites.

Two-dimensional to three-dimensional dry fibre preforming (2023)
Book Chapter
Chen, S., & Harper, L. (2023). Two-dimensional to three-dimensional dry fibre preforming. In Design and Manufacture of Structural Composites (101-123). Elsevier. https://doi.org/10.1016/B978-0-12-819160-6.00005-6

Preforming is the process of converting two-dimensional (2D) intermediate fibre products, such as fabrics and mats, into complex three-dimensional (3D) shapes to resemble the geometry of the final component. Preforming is a necessary step for all liq... Read More about Two-dimensional to three-dimensional dry fibre preforming.

Cost, rate, and robustness (2023)
Book Chapter
Hancock, S., & Harper, L. (2023). Cost, rate, and robustness. In Design and Manufacture of Structural Composites (447-471). Elsevier. https://doi.org/10.1016/B978-0-12-819160-6.00022-6

This chapter outlines the most important considerations for the economic evaluation of composites, as assessing both cost and performance in parallel is critical for designing and manufacturing efficient applications. The cost of raw materials is oft... Read More about Cost, rate, and robustness.

A global-to-local sub modelling approach to investigate the effect of lubrication during double diaphragm forming of multi-ply biaxial non-crimp fabric preforms (2023)
Journal Article
Yu, F., Chen, S., Lawrence, G. D., Warrior, N. A., & Harper, L. T. (2023). A global-to-local sub modelling approach to investigate the effect of lubrication during double diaphragm forming of multi-ply biaxial non-crimp fabric preforms. Composites Part B: Engineering, 254, Article 110590. https://doi.org/10.1016/j.compositesb.2023.110590

The forming behaviour of preforms constructed from multiple plies of Non-Crimp Fabric (NCF) has been investigated for manufacturing a complex double-curved geometry using Double Diaphragm Forming (DDF). An established multi-resolution finite element... Read More about A global-to-local sub modelling approach to investigate the effect of lubrication during double diaphragm forming of multi-ply biaxial non-crimp fabric preforms.

Introduction (2023)
Book Chapter
Harper, L., & Clifford, M. (2023). Introduction. In L. Harper, & M. Clifford (Eds.), Design and Manufacture of Structural Composites (3-17). Elsevier. https://doi.org/10.1016/b978-0-12-819160-6.00009-3

Fibre-reinforced polymer composites are acknowledged to offer some of the highest specific properties (stiffness, strength) of any engineering materials, but this chapter takes a look at why these materials are not more widely adopted for general str... Read More about Introduction.

Reinforcing fibres (2023)
Book Chapter
Parsons, A. (2023). Reinforcing fibres. In L. Harper, & M. Clifford (Eds.), Design and Manufacture of Structural Composites (19-34). Elsevier. https://doi.org/10.1016/B978-0-12-819160-6.00008-1

This chapter provides information on the type of reinforcing fibres commonly used in polymer composites. Inorganic and organic fibres are described along with general information on their manufacture, applications, and representative properties. Suit... Read More about Reinforcing fibres.

Rapidly predicting the effect of tool geometry on the wrinkling of biaxial NCFs during composites manufacturing using a deep learning surrogate model (2023)
Journal Article
Viisainen, J., Yu, F., Codolini, A., Chen, S., Harper, L., & Sutcliffe, M. (2023). Rapidly predicting the effect of tool geometry on the wrinkling of biaxial NCFs during composites manufacturing using a deep learning surrogate model. Composites Part B: Engineering, 253, Article 110536. https://doi.org/10.1016/j.compositesb.2023.110536

A deep learning surrogate model is developed to rapidly predict the wrinkling patterns of a biaxial non-crimp fabric (NCF) layup for any given tool geometry during forming. The underlying dataset of finite element simulations is used to investigate t... Read More about Rapidly predicting the effect of tool geometry on the wrinkling of biaxial NCFs during composites manufacturing using a deep learning surrogate model.

Modelling the effects of patch-plug configuration on the impact performance of patch-repaired composite laminates (2023)
Journal Article
Liu, H., Liu, J., Hall, Z. E., Brooks, R. A., Crocker, J. W., Joesbury, A. M., Harper, L. T., Blackman, B. R., Kinloch, A. J., & Dear, J. P. (2023). Modelling the effects of patch-plug configuration on the impact performance of patch-repaired composite laminates. Composites Science and Technology, 233, Article 109917. https://doi.org/10.1016/j.compscitech.2023.109917

The patch-plug configuration has been widely used to repair composite structures and restore the structural integrity of damaged composites. In the present research, single-sided CFRP patch-repaired panels, with different patch-plug configurations, a... Read More about Modelling the effects of patch-plug configuration on the impact performance of patch-repaired composite laminates.

The influence of inter-ply friction during double-diaphragm forming of biaxial NCFs (2023)
Journal Article
Lawrence, G. D., Chen, S., Warrior, N. A., & Harper, L. T. (2023). The influence of inter-ply friction during double-diaphragm forming of biaxial NCFs. Composites Part A: Applied Science and Manufacturing, 167, Article 107426. https://doi.org/10.1016/j.compositesa.2023.107426

Inter-ply friction plays an important role in the formation of defects in automated preforming of complex components, as relative sliding between plies can generate local compressive stresses in the direction of the primary yarns, leading to out-of-p... Read More about The influence of inter-ply friction during double-diaphragm forming of biaxial NCFs.

Experimental and numerical investigations on the impact behaviour of pristine and patch-repaired composite laminates (2022)
Journal Article
Liu, H., Brooks, R. A., Hall, Z. E., Liu, J., Crocker, J. W., Joesbury, A. M., Harper, L. T., Blackman, B. R., Kinloch, A. J., & Dear, J. P. (2022). Experimental and numerical investigations on the impact behaviour of pristine and patch-repaired composite laminates. Philosophical Transactions A: Mathematical, Physical and Engineering Sciences, 380(2232), Article 20210340. https://doi.org/10.1098/rsta.2021.0340

The present paper investigates the impact behaviour of both pristine carbon-fibre-reinforced-plastic (CFRP) composite laminates and repaired CFRP laminates. For the patch-repaired CFRP specimen, the pristine CFRP panel specimen has been damaged by cu... Read More about Experimental and numerical investigations on the impact behaviour of pristine and patch-repaired composite laminates.

Multiscale viscoplastic modeling of recycled glass fiber-reinforced thermoplastic composites: Experimental and numerical investigations (2022)
Journal Article
Nachtane, M., Meraghni, F., Chatzigeorgiou, G., Harper, L., & Pelascini, F. (2022). Multiscale viscoplastic modeling of recycled glass fiber-reinforced thermoplastic composites: Experimental and numerical investigations. Composites Part B: Engineering, 242, Article 110087. https://doi.org/10.1016/j.compositesb.2022.110087

One of the main challenges facing fiber-reinforced polymer composites is the lack of options for end-of-life recycling. The environmental impact of waste materials disposed of at landfill sites, by incineration, or by erratic dispersion in the enviro... Read More about Multiscale viscoplastic modeling of recycled glass fiber-reinforced thermoplastic composites: Experimental and numerical investigations.

The effectiveness of patch repairs to restore the impact properties of carbon-fibre reinforced-plastic composites (2022)
Journal Article
Hall, Z., Liu, J., Brooks, R., Liu, H., Crocker, J., Joesbury, A., Harper, L., Blackman, B. R., Kinloch, A., & Dear, J. (2022). The effectiveness of patch repairs to restore the impact properties of carbon-fibre reinforced-plastic composites. Engineering Fracture Mechanics, 270, Article 108570. https://doi.org/10.1016/j.engfracmech.2022.108570

The present paper studies the low-velocity impact testing of carbon-fibre reinforced-plastic (CFRP) pristine and patch-repair CFRP panels. Firstly, the effect of repeated impacts on the pristine CFRP damage growth is considered at impact energies of... Read More about The effectiveness of patch repairs to restore the impact properties of carbon-fibre reinforced-plastic composites.