The interlaminar and intralaminar fracture toughness of carbon-fibre/polymer composites: The effect of temperature

Abstract The aim of this study was to identify the effect of material type (matrix and reinforcement) and process parameters, on the mechanical properties of 3D Printed long-fibre reinforced polymer composites manufactured using a commercial 3D Printer (Mark Two). The effect of matrix material (Onyx or polyamide), reinforcement type (Carbon, Kevlar®, and HSHT glass), volume of reinforcement, and reinforcement lay-up orientation on both Ultimate Tensile Strength (UTS) and Flexural Modulus were investigated. For Onyx, carbon fibre reinforcement offered the largest increase in both UTS and Flexural Modulus over unreinforced material (1228 ± 19% and 1114 ± 6% respectively). Kevlar® and HSHT also provided improvements but these were less significant. Similarly, for Nylon, the UTS and Flexural Modulus were increased by 1431 ± 56% and 1924 ± 5% by the addition of carbon fibre reinforcement. Statistical analysis indicated that changing the number of layers of reinforcement had the largest impact on both UTS and Flexural Strength, and all parameters were statistically significant.

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Effect of temperature on the fracture toughness of wood under mode I quasi-static loading

Construction and Building Materials ◽

10.1016/j.conbuildmat.2019.07.036 ◽

2019 ◽

Vol 223 ◽

pp. 863-869

Author(s):

N. Dourado ◽

M.F.S.F. de Moura

Keyword(s):

Fracture Toughness ◽

Static Loading ◽

Effect Of Temperature ◽

Mode I

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Flexed plate impact, part 7. low energy and excess energy impacts on carbon fibre-reinforced polymer composites

Composites ◽

10.1016/0010-4361(88)90237-6 ◽

1988 ◽

Vol 19 (3) ◽

pp. 193-203 ◽

Cited By ~ 27

Author(s):

P.E. Reed ◽

S. Turner

Keyword(s):

Carbon Fibre ◽

Polymer Composites ◽

Excess Energy ◽

Low Energy ◽

Plate Impact ◽

Reinforced Polymer ◽

Carbon Fibre Reinforced Polymer ◽

Fibre Reinforced Polymer

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Sequential Laser–Mechanical Drilling of Thick Carbon Fibre Reinforced Polymer Composites (CFRP) for Industrial Applications

Polymers ◽

10.3390/polym13132136 ◽

2021 ◽

Vol 13 (13) ◽

pp. 2136

Author(s):

Sharizal Ahmad Sobri ◽

Robert Heinemann ◽

David Whitehead

Keyword(s):

Carbon Fibre ◽

Polymer Composites ◽

Weight Ratio ◽

High Strength ◽

Industrial Applications ◽

Fibre Laser ◽

Reinforced Polymer ◽

Carbon Fibre Reinforced Polymer ◽

Fibre Reinforced Polymer ◽

Thrust And Torque

Carbon fibre reinforced polymer composites (CFRPs) can be costly to manufacture, but they are typically used anywhere a high strength-to-weight ratio and a high steadiness (rigidity) are needed in many industrial applications, particularly in aerospace. Drilling composites with a laser tends to be a feasible method since one of the composite phases is often in the form of a polymer, and polymers in general have a very high absorption coefficient for infrared radiation. The feasibility of sequential laser–mechanical drilling for a thick CFRP is discussed in this article. A 1 kW fibre laser was chosen as a pre-drilling instrument (or initial stage), and mechanical drilling was the final step. The sequential drilling method dropped the overall thrust and torque by an average of 61%, which greatly increased the productivity and reduced the mechanical stress on the cutting tool while also increasing the lifespan of the bit. The sequential drilling (i.e., laser 8 mm and mechanical 8 mm) for both drill bits (i.e., 2- and 3-flute uncoated tungsten carbide) and the laser pre-drilling techniques has demonstrated the highest delamination factor (SFDSR) ratios. A new laser–mechanical sequence drilling technique is thus established, assessed, and tested when thick CFRP composites are drilled.

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Mixed-Mode Interlaminar Fracture Toughness of Glass and Carbon Fibre Powder Epoxy Composites—For Design of Wind and Tidal Turbine Blades

Materials ◽

10.3390/ma14092103 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2103

Author(s):

Christophe Floreani ◽

Colin Robert ◽

Parvez Alam ◽

Peter Davies ◽

Conchúr M. Ó. Brádaigh

Keyword(s):

Fracture Toughness ◽

Carbon Fibre ◽

Composite Structures ◽

Mixed Mode ◽

Epoxy Composites ◽

Mode I ◽

Mode Ii ◽

Pure Mode ◽

Interlaminar Fracture Toughness ◽

Interlaminar Fracture

Powder epoxy composites have several advantages for the processing of large composite structures, including low exotherm, viscosity and material cost, as well as the ability to carry out separate melting and curing operations. This work studies the mode I and mixed-mode toughness, as well as the in-plane mechanical properties of unidirectional stitched glass and carbon fibre reinforced powder epoxy composites. The interlaminar fracture toughness is studied in pure mode I by performing Double Cantilever Beam tests and at 25% mode II, 50% mode II and 75% mode II by performing Mixed Mode Bending testing according to the ASTM D5528-13 test standard. The tensile and compressive properties are comparable to that of standard epoxy composites but both the mode I and mixed-mode toughness are shown to be significantly higher than that of other epoxy composites, even when comparing to toughened epoxies. The mixed-mode critical strain energy release rate as a function of the delamination mode ratio is also provided. This paper highlights the potential for powder epoxy composites in the manufacturing of structures where there is a risk of delamination.

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