A modern account of Iosipescu testing

Stojcevski, Filip; Hilditch, Tim; Henderson, Luke C.

doi:10.1016/j.compositesa.2018.02.011

Cited by 37 publications

(16 citation statements)

References 118 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The Iosipescu shear test can determine interfacial shear strength (IFSS) of composite materials, and was recently reviewed [ 11 ]. Also known as the V-notch shear test, this protocol creates a region of pure shear across a notched sample for which the mechanical properties of a material can be quantified as a measure of specimen geometry and failure load [ 12 , 13 , 14 , 15 ].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Effect of Tow Size and Interface Interaction on Interfacial Shear Strength Determined by Iosipescu (V-Notch) Testing in Epoxy Resin

et al. 2018

Self Cite

View full text Add to dashboard Cite

Testing methodologies to accurately quantify interfacial shear strength (IFSS) are essential in order to understand fiber-matrix adhesion. While testing methods at a microscale (single filament fragmentation test—SFFT) and macroscale (Short Beam Shear—SBS) are wide spread, each have their own shortcomings. The Iosipescu (V-notch) tow test offers a mesoscale bridge between the microscale and macroscale whilst providing simple, accurate results with minimal time investment. However, the lack of investigations exploring testing variables has limited the application of Iosipescu testing to only a handful of studies. This paper assesses the effect of carbon fiber tow size within the Iosipescu tow test for epoxy resin. Tow sizes of 3, 6, and 9 k are eminently suitable, while more caution must be shown when examining 12, and 15 k tows. In this work, tows at 18 and 24 k demonstrated failure modes not derived from interfacial failure, but poor fiber wetting. A catalogue of common fracture geometries is discussed as a function of performance for the benefit of future researchers. Finally, a comparison of commercial (T300), amine (T300-Amine), and ethyl ester (T300-Ester) surface modified carbon fibers was conducted. The outcomes of this study showed that the Iosipescu tow test is inherently less sensitive in distinguishing between similar IFSS but provides a more ‘real world’ image of the carbon fiber-epoxy interface in a composite material.

show abstract

Section: Introductionmentioning

confidence: 99%

“…Unfortunately, reported academic and industrial applications using the Iosipescu test are limited [ 11 ] and of existing research, the overwhelming majority is focused on Iosipescu laminates. Deng et al [ 20 ] remains one of the only cases that has explored the Iosipescu tow test as an effective means to observe interface interactions.…”

Section: Introductionmentioning

confidence: 99%

Effect of Tow Size and Interface Interaction on Interfacial Shear Strength Determined by Iosipescu (V-Notch) Testing in Epoxy Resin

et al. 2018

Self Cite

View full text Add to dashboard Cite

show abstract

“…77 , 78 In particular, Stojcevski et al. 79 raised various concerns regarding notch sensitivity, specimen twisting, and stress states in the gage section. Their study explained how these concerns have been resolved by a material modeling technique.…”

Section: Comparison Of Composite Materials Testing Methodsmentioning

confidence: 99%

“…Stojcevski et al. 79 demonstrated the typical failure modes and fracture mechanisms of Iosipescu specimens for carbon fiber reinforced epoxy composites. In their results, it was obvious that the failure modes were closely related to the individual fiber tow size, lay-up patterns of the specimen (e.g.…”

Section: Comparison Of Composite Materials Testing Methodsmentioning

confidence: 99%

“…A schematic representation of the typical failure modes for Iosipescu specimens is shown in Figure 11

Figure 11.Typical failure modes of V-notch specimens: (a) to (d) refer to acceptable failure in shear mode; (e) and (f) refer to unacceptable failure in nonshear mode (reproduced from Stojcevski et al. 79 with permission of Elsevier).. The failures are as follows: (1) type A (i.e.…”

Section: Comparison Of Composite Materials Testing Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Review of material test standardization status for the material qualification of laminated thermosetting composite structures

Park

Choi

2020

Journal of Reinforced Plastics and Composites

View full text Add to dashboard Cite

This paper presents a review of recent literature related to the static mechanical testing of thermoset-based carbon fiber reinforced composites and introduces a material qualification methodology to generate statistically-based allowable design values for aerospace application. Although most test methods have been found to be effective in determining the specific material properties by incorporating them into the material qualification and quality control provisions, a full validation to clarify the behavior of thermoset-based laminated composite materials is currently lacking, particularly with regard to the characterization of compressive, in-plane, interlaminar shear, and damage tolerance properties. The present study obtains information on the different types of test method that can be employed within the same material properties, and makes an in-depth experimental comparison based on the past literatures. A discussion on the scope of theoretical analysis involves a description of how the proposed test method can be adequate for obtaining more accurate material properties. This discussion is directly applicable to the assessment of material nonlinearity and the geometrical effect of specimens. Finally, the resulting failure modes and the effect of each material property are studied to aid the understanding of the load distribution and behavior of laminated composite materials.

show abstract

Using digital image correlation for in situ strain and damage monitoring in hybrid fiber laminates under in‐plane shear loading

et al. 2021

View full text Add to dashboard Cite

Utilizing resistive strain gauges for V-notch shear tests in fiber reinforced laminates is usually limited to low strain values due to technical uncertainties imposed by the measurement technique and also the progressive damage development in the notched region of the composite. Therefore, this study investigates an alternative approach by using digital image correlation system and further comparison with resistive strain gauge to identify the effect of heterogenous nature of damage development on measurement results. Moreover, glass/carbon fiber hybrid and non-hybrid laminates are tested in two major directions through the same approach to determine the effect of stacking sequence in spatial microdamage accumulation. It is shown that tailoring appropriate region of interest for full field strain measurement at various stages of loading enables proper monitoring of microdamage accumulation and thereby delivers a precise stressstrain behavior for hybrid and non-hybrid laminates. Comparison of the strain maps for hybrid laminates tested in 0 direction, shows that the presence of carbon plies at the surface results in uniform strain distribution between the notches of the test sample. In contrast, a non-homogeneous strain map with separate regions of high strain gradient are observed for hybrid specimens with glass plies at surface, which can cause underestimation of average shear strain by resistive strain gauges. On the other hand, it is shown that strain maps for hybrid samples tested at 90 configuration is analogous regardless of the stacking sequence, and damage accumulation in these samples is most likely related to relative volume fraction of various fibers in hybrid laminate.

show abstract

A modern account of Iosipescu testing

Cited by 37 publications

References 118 publications

Effect of Tow Size and Interface Interaction on Interfacial Shear Strength Determined by Iosipescu (V-Notch) Testing in Epoxy Resin

Effect of Tow Size and Interface Interaction on Interfacial Shear Strength Determined by Iosipescu (V-Notch) Testing in Epoxy Resin

Review of material test standardization status for the material qualification of laminated thermosetting composite structures

Using digital image correlation for in situ strain and damage monitoring in hybrid fiber laminates under in‐plane shear loading

Contact Info

Product

Resources

About