An analytical approach for the design of carbon-fibre-reinforced polymer laminates with minimised thermal expansion

In recent years, externally bonded carbon fibre–reinforced polymer has been considered an innovative way to strengthen steel structures attributed to its high strength-to-weight ratio, excellent corrosion resistance and fatigue performance. This article presents an experimental and numerical study on the fatigue behaviour of defected steel beams strengthened with carbon fibre–reinforced polymer laminates, with a special focus on the effect of interfacial debonding. Analytical modelling and numerical simulation confirmed that the interfacial debonding had a pronounced effect on carbon fibre–reinforced polymer strain and stress intensity factor at the crack front. After introducing interfacial debonding from experimental findings into the numerical analysis, the fatigue life and crack propagation versus cycle numbers of the specimens compared well with the test results. Based on the current experimental program, specimens with Sikadur 30 were more prone to debonding failure; therefore, Araldite 420 is suggested for strengthening schemes.

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Through-thickness electric conductivity of toughened carbon-fibre-reinforced polymer laminates with resin-rich layers

Composites Science and Technology ◽

10.1016/j.compscitech.2015.11.018 ◽

2016 ◽

Vol 122 ◽

pp. 67-72 ◽

Cited By ~ 31

Author(s):

Yoshiyasu Hirano ◽

Takuya Yamane ◽

Akira Todoroki

Keyword(s):

Carbon Fibre ◽

Electric Conductivity ◽

Reinforced Polymer ◽

Carbon Fibre Reinforced Polymer ◽

Fibre Reinforced Polymer ◽

Polymer Laminates

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Toughening mechanism of carbon fibre-reinforced polymer laminates containing inkjet-printed poly(methyl methacrylate) microphases

Journal of Composite Materials ◽

10.1177/0021998317727133 ◽

2017 ◽

Vol 52 (11) ◽

pp. 1567-1576 ◽

Cited By ~ 2

Author(s):

Yi Zhang ◽

Jonathan Stringer ◽

Alma Hodzic ◽

Patrick J Smith

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Carbon Fibre ◽

Spherical Shape ◽

Energy Minimisation ◽

Reinforced Polymer ◽

Carbon Fibre Reinforced Polymer ◽

Fibre Reinforced Polymer ◽

Toughness Testing ◽

Polymer Laminates

It has previously been demonstrated that inkjet-printed thermoplastic microphases are capable of producing a significant increase in mode I interlaminar fracture toughness ( G Ic) in carbon fibre-reinforced polymer with no significant reduction in other mechanical properties or increase in parasitic weight. In this work, the evolution of the microphase structure during processing and how this is influenced by the chosen printing parameters were investigated. Samples were prepared that enabled monitoring of the microphases during all steps of fabrication, with the thermoplastic polymer found to form a discrete spherical shape due to surface energy minimisation. Based upon the morphology and properties of the thermoplastic microphases, it was hypothesised that the increased toughness was due to a combination of crack deflection and plastic deformation of the microphases. Samples were produced for the double cantilever beam fracture toughness testing using the same printing conditions, and both G Ic values and scanning electron microscopy of the fracture surface supported the proposed hypothesis. The feasibility of selective toughening is also demonstrated, which presents potential to tailor the mechanical properties of the carbon fibre-reinforced polymer spatially.

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