Interfacial performance of phenolic‐sized continuous carbon fiber‐reinforced phenolic resin composites with different impregnation nozzle diameters via <scp>3D</scp> printing

Continuous fiber reinforced thermoplastic composites (CFRTPCs) prepared by fused deposition modeling (FDM) have gained great attention for the benefit of preparing products without molds. However, unexpected debonding and defects are derived from insufficient impregnation between fiber and matrix in 3D‐printed samples, resulting in weak interfacial performance. In this work, a polyetherimide (PEI) sizing agent was used to improve the fiber‐matrix interfaces, and the interlaminar shear strength (ILSS) of the continuous carbon fiber reinforced poly(ether‐ketone‐ketone) composites was increased to 27.1 MPa, 12.4% higher than that of unmodified composite. Meanwhile, the performance of CFRTPCs is affected by process parameters in FDM. Build orientation of FDM was discussed and PEI weakened the anisotropy of samples' mechanical properties because the performance variation caused by build orientation decreased from 86.8% to 65.2%, which may be beneficial for the forming freedom of in situ impregnated FDM. The addition of PEI makes sense to apply in situ impregnated FDM in high‐tech fields.Highlights CCF/PEKK composites were prepared by in situ impregnated FDM. ILSS of flat‐oriented CCF/PEKK was 86.8% higher than that of on‐edge. 5 wt% PEI sizing agent promoted adhesion of CCF and PEKK to obtain the best mechanical properties. PEI weakened the anisotropy of samples' mechanical properties, which was conducive to forming freedom.

R_{normalr} = \frac{m_{normalr 1}}{M_{normalr 1}} \times 100 %

M = M_{normalr} + M_{normalf}

m = R_{normalr} M_{normalr} + M_{normalf}

M_{normalr} = \frac{M - m}{1 - R_{normalr}}

M_{normalf} = M - M_{r}

V_{normalf} = \frac{M_{f}}{ρ_{normalf} V} \times 100 %

φ = 100 % - \frac{\frac{M_{f}}{ρ_{f}} + \frac{M_{r}}{ρ_{r}}}{V} \times 100 %

Section: Characterizationsmentioning

confidence: 99%

Interfacial performance and build orientation of 3D‐printed poly(ether‐ketone‐ketone) reinforced by continuous carbon fiber

Fan,

Zhou,

Zhang

et al. 2023

“…This has facilitated their widespread use in various fields including aerospace, automobile manufacturing, construction engineering, energy industry, and biomedicine. [1][2][3] However, despite the numerous benefits of composite laminates, addressing the issue of low-velocity impact (LVI) is crucial during their practical application. LVI may cause microscopic damage to the material, which may not be apparent on the surface but can seriously affect the bearing capacity of the structure, thereby affecting its overall performance and service life.…”

Section: Introductionmentioning

confidence: 99%

Research on low‐velocity impact resistance of carbon fiber composite laminates

Hou,

Aymerich,

Feng

2024

This research conducts a comprehensive experimental and numerical analysis of carbon fiber composite laminates under low‐velocity impact conditions. Split Hopkinson Pressure Bar (SHPB) was employed to conduct impact testing on laminates with two layup sequences ( and ) under impacts ranging from 2 to 6 J. For assessing damage in laminates, a comprehensive progressive damage model and a simplified model were developed. The primary distinction between these models lies in the fact that the former incorporates the strengthening effect of compression on the delamination behavior, while the latter does not. Both models produce a good agreement with experimental results in terms of force–time, force–displacement curves, and absorbed energies. However, notable differences were noted in the predicted internal damage; the simplified model was underpredicted in terms of damage size and distribution compared to the comprehensive progressive damage model.Highlights Impact tests were conducted on and composites. In order to simulate damage caused by impacts in laminates, an energy‐based damage model was created, and cohesive elements were utilized to model interlaminar delamination. The strengthening effect of compression was explored. Distinct damage criteria were established for two cases. Damage detection of composites by x‐rays.

The theoretical and experimental buckling analysis of a nanocomposite beams reinforced by nanorods made of recycled materials

Bargozini,

Mohammadimehr

2023

In this article, the numerical and experimental results for buckling analysis of a nanocomposite beams reinforced by nanorods are studied and compared. The Chebyshev–Ritz method is used to calculate the buckling numerically and compare it with the buckling test. Epoxy resin, glass's fiber, and nanorods are used to make composites. These nanorods are made using recycled materials. Also, bending and tensile tests are used to obtain the properties of these composites. In addition, the effect of various parameters such as Young's modulus, temperature change, Poisson's ratio, and boundary conditions, the strain gradient parameter, and different shape function is investigated. The addition of nanorods increases the strength and stiffness of composites and increases the critical buckling load. Actually, the made nanorods are used as a reinforcement in matrix, thus in the made nanocomposites, fracture and buckling tests are done and the results indicate that the inclusion of nanorods (0.32%) increases the critical buckling load by 16.4%. A facile hydrothermal method to synthesis the nano rodes has a less cost with the other methods, thus by adding a small percentage of it to the composite, the stiffness of the structure increases. According to the results and the significant increase in Young's modulus and critical buckling load and the cost‐effectiveness of carbon nanorods (CNRs) made from recycled materials, these environmentally friendly reinforcements can be used in various industries such as machine body construction, automobile manufacturing, shipbuilding and construction of type's turbines.Highlights Using potato peels and hydrothermal methods, CNRs produced. These CNRs are useful, and production is cheap and no harm environmental. Buckling sample include of glass fiber, without and with CNRs and epoxy resin. Third order shear deformation beam theory and Chebyshev–Ritz are used Theoretical and experimental buckling critical load are compared.