Experimental and numerical benchmark study of mode II interlaminar fracture toughness of unidirectional GFRP laminates under shear loading using the end-notched flexure (ENF) test

Gliszczyński, Adrian; Wiącek, Nina

doi:10.1016/j.compstruct.2020.113190

Cited by 32 publications

(17 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The results obtained with this method were the ( G IIC ) mode II interlaminar fracture toughness. The data of the load versus displacement were recorded to determine the mode II interlaminar fracture toughness, and G IIC was calculated using Equation (1) [ 68 ]:

where h is the half specimen thickness, P is the maximum fracture test load of the corresponded crack length, a is the crack length, and b is the sample width.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Fabrication and Thermo-Electro and Mechanical Properties Evaluation of Helical Multiwall Carbon Nanotube-Carbon Fiber/Epoxy Composite Laminates

et al. 2021

View full text Add to dashboard Cite

The development of advanced composite materials has taken center stage because of its advantages over traditional materials. Recently, carbon-based advanced additives have shown promising results in the development of advanced polymer composites. The inter- and intra-laminar fracture toughness in modes I and II, along with the thermal and electrical conductivities, were investigated. The HMWCNTs/epoxy composite was prepared using a multi-dispersion method, followed by uniform coating at the mid-layers of the CF/E prepregs interface using the spray coating technique. Analysis methods, such as double cantilever beam (DCB) and end notched flexure (ENF) tests, were carried out to study the mode I and II fracture toughness. The surface morphology of the composite was analyzed using field emission scanning electron microscopy (FESEM). The DCB test showed that the fracture toughness of the 0.2 wt.% and 0.4 wt.% HMWCNT composite laminates was improved by 39.15% and 115.05%, respectively, compared with the control sample. Furthermore, the ENF test showed that the mode II interlaminar fracture toughness for the composite laminate increased by 50.88% and 190%, respectively. The FESEM morphology results confirmed the HMWCNTs bridging at the fracture zones of the CF/E composite and the improved interlaminar fracture toughness. The thermogravimetric analysis (TGA) results demonstrated a strong intermolecular bonding between the epoxy and HMWCNTs, resulting in an improved thermal stability. Moreover, the differential scanning calorimetry (DSC) results confirmed that the addition of HMWCNT shifted the Tg to a higher temperature. An electrical conductivity study demonstrated that a higher CNT concentration in the composite laminate resulted in a higher conductivity improvement. This study confirmed that the demonstrated dispersion technique could create composite laminates with a strong interfacial bond interaction between the epoxy and HMWCNT, and thus improve their properties.

show abstract

where h is the half specimen thickness, P is the maximum fracture test load of the corresponded crack length, a is the crack length, and b is the sample width.…”

Section: Methodsmentioning

confidence: 99%

“…The results obtained with this method were the (G IIC ) mode II interlaminar fracture toughness. The data of the load versus displacement were recorded to determine the mode II interlaminar fracture toughness, and G IIC was calculated using Equation (1) [68]:…”

Section: End Notched Flexure (Enf) Testmentioning

confidence: 99%

Fabrication and Thermo-Electro and Mechanical Properties Evaluation of Helical Multiwall Carbon Nanotube-Carbon Fiber/Epoxy Composite Laminates

et al. 2021

View full text Add to dashboard Cite

show abstract

“…It was found that crack growth starts in the center of DCB specimens, whereas it starts at the edges of ENF specimens. 51,52,53 Therefore, patches of reduced SERR at these edges will further increase the damage for the crack onset in the ENF load case.…”

Section: Effect Of the Positionmentioning

confidence: 99%

A numerical study on the effect of local cohesive property variation to single mode fracture models

Linke¹,

Lammering²

2022

Preprint

View full text Add to dashboard Cite

In this work, the effect of local cohesive property variation on the fracture behavior of single mode fracture models is numerically investigated. In this context, 3D models for the double cantilever beam test and the end-notched flexure test are built. The bonded interface is considered in two variants: a) homogeneous and b) heterogeneous with a local patch of varying cohesive properties. In order to evaluate the effect of the patch to the fracture behavior, the cumulative damage is introduced as a criterion. Parameters of the patch, i.e. material properties, geometry and position, are varied in a parametric study. Conclusions about their effect on the cumulative damage are drawn and justified. Different conditions of the crack growth are considered, i.e. crack onset and propagation. The results of the study outline the importance of the geometrical design of the patch. Especially the orientation of non-squared patches has a large, disproportional effect on the cumulative damage. Also the fracture mode plays an important role. The obtained information can be used to optimize interlaminar integrated sensors as a mean of structural health monitoring.

show abstract

“…However, direct measurement methods for material fracture energy are scarce. The usual indirect method is to obtain the interlaminar fracture toughness by the prefabricating crack in the composite and performing the Double-Cantilever Beam (DCB) test [34] and End Notched Flexure (ENF) test [35] to measure the interlaminar fracture toughness, based on which to approximate the fracture energy in the matrix direction [8,36] (where failure behavior is dominated by the matrix rather than fibers). As for fracture energy in the fiber-dominated direction, the above method is not applicable, and few feasible test methods exist.…”

Section: Introductionmentioning

confidence: 99%

A novel energy‐based framework for characterizing the strain‐softening behavior of CFRP composites using cyclic loading

Zhang

Liu

et al. 2022

Polymer Composites

View full text Add to dashboard Cite

Complex failure modes of carbon fiber reinforced polymer (CFRP) composites create significant challenges for CFRP components' progressive damage analysis (PDA). Though important in PDA, the phenomenological strain‐softening model (SSM) for characterizing the degradation behavior in the fiber‐parallel direction (dominated by fiber breakage) of CFRP is difficult to be constructed by current approaches due to the poor toughness of carbon fibers. The work aims to obtain a refined SSM of plain woven CFRP composites through experimental methods and apply it to the PDA of corresponding components. A novel phenomenological cyclic‐loading‐based strain‐softening model (CLSSM) was proposed based on the theory of equivalent dissipation energy during static and cyclic loading. Firstly, the release behavior of dissipation energy during the cyclic loading process was researched. Secondly, a newly designed search algorithm taking degraded mechanical properties during cyclic loading as input and taking the static strain‐softening curve as output was utilized to build up CLSSM. Thirdly, a three‐point bending test was conducted and a corresponding numerical model was constructed for comparison to verify the proposed model. The entire framework is highly programmatic, and results show that CLSSM is fast for characterizing the strain‐softening behavior, and effectively simulates the progressive failure process of CFRP components.

show abstract

Experimental and numerical benchmark study of mode II interlaminar fracture toughness of unidirectional GFRP laminates under shear loading using the end-notched flexure (ENF) test

Cited by 32 publications

References 38 publications

Fabrication and Thermo-Electro and Mechanical Properties Evaluation of Helical Multiwall Carbon Nanotube-Carbon Fiber/Epoxy Composite Laminates

Fabrication and Thermo-Electro and Mechanical Properties Evaluation of Helical Multiwall Carbon Nanotube-Carbon Fiber/Epoxy Composite Laminates

A numerical study on the effect of local cohesive property variation to single mode fracture models

A novel energy‐based framework for characterizing the strain‐softening behavior of CFRP composites using cyclic loading

Contact Info

Product

Resources

About