The Effects of Through-thickness Compression on the Interlaminar Shear Response of Laminated Fiber Composites

Fiber composites with a three-dimensional braided reinforcement architecture have higher fiber volume content and Z-fiber content compared to a two-dimensional braided reinforcement architecture; as a result, the shear strength increases. Porous oxide fiber composites (OFCs) have the inherent weakness of a low interlaminar shear strength, which can be specifically increased by the use of a three-dimensional fiber reinforcement. In this work, the braiding process chain for processing highly brittle oxide ceramic fibers is modified; as a consequence, a bobbin, which protects the filament, is developed and quantitatively evaluated on a test rig with regard to tension and filament breakage. Subsequently, a braiding process is designed which takes into account fiber-protecting aspects, and a three-dimensional reinforced demonstrator is produced and tested. After impregnation with an Al2O3-ZrO2 slurry, by either a prepreg process or a vacuum-assisted process, as well as subsequent sintering, the three-dimensional braid-reinforced OFC exhibits an interlaminar shear strength (ILSS) which is higher than that of two-dimensional braid- or fabric-reinforced samples by 64–95%. The influence of the manufacturing process on the relative macropore content is investigated and correlated with the mechanical properties.

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Effects of Epoxy/SiO2 Hybrid Sizing on the Mechanical Properties of Carbon Fiber Composites

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.121-123.1253 ◽

2007 ◽

Vol 121-123 ◽

pp. 1253-1256 ◽

Cited By ~ 3

Author(s):

Chun Hong Zhang ◽

Z.Q. Zhang ◽

H.L. Cao

Keyword(s):

Mechanical Properties ◽

Carbon Fiber ◽

Sol Gel ◽

Fiber Surface ◽

Fiber Composites ◽

Carbon Fiber Composites ◽

Impact Properties ◽

Ft Ir ◽

Gel Technique ◽

Interlaminar Shear

A novel epoxy/SiO2 hybrid sizing for carbon fiber surface was prepared through sol-gel technique, the structure of the sizing were analyzed, and the effects of the sizing on mechanical properties of carbon fiber composites were also investigated. The analyses by FT-IR and SEM indicated that epoxy/SiO2 hybrid sizing was prepared successfully, SiO2 particles dispersed in the hybrid sizing film homogeneously with nanoscale. The analyses on interlaminar shear strength (ILSS) and impact properties of composites showed that the epoxy/nano-SiO2 hybrid sizing increased ILSS and improved impact properties obviously at the same time.

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NanoSiO2 strengthens and toughens epoxy resin/basalt fiber composites by acting as a nano-mediator

Journal of Polymer Engineering ◽

10.1515/polyeng-2018-0056 ◽

2018 ◽

Vol 39 (1) ◽

pp. 10-15 ◽

Cited By ~ 1

Author(s):

Xi Li ◽

Guoming Li ◽

Xiaohong Su

Keyword(s):

Basalt Fiber ◽

Fiber Composites ◽

Mechanical Tests ◽

Basalt Fibers ◽

Large Numbers ◽

New Type ◽

Interlaminar Shear ◽

Application Fields ◽

External Forces ◽

Modified Epoxy

AbstractA new type of material was prepared by modifying epoxy/basalt fiber composites with nanoSiO2. Mechanical tests showed that the nanoSiO2-modified epoxy/basalt fiber composites displayed significant improvement over the unmodified epoxy/basalt fiber composites in interlaminar shear strength and notch impact strength. Scanning electron microscopy revealed that the nanoSiO2was homogeneously dispersed in the epoxy matrix and adsorbed large numbers of epoxy molecules onto the surface. Many of the nanoSiO2-epoxy complexes tightly surrounded basalt fibers to form transition layers. Therefore, nanoSiO2can act as a nano-mediator to promote epoxy molecules to infiltrate between and bind to basalt fibers, which enhances the synergistic cooperation between epoxy and basalt fibers in resisting external forces. This study indicates that modification with nanoSiO2is an effective pathway to improve the performance of epoxy/basalt fiber composites and broaden their application fields.

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Interfacial Water and Adhesion Loss of Polymer Coatings on a Siliceous Substrate

MRS Proceedings ◽

10.1557/proc-385-57 ◽

1995 ◽

Vol 385 ◽

Cited By ~ 7

Author(s):

T. Nguyen ◽

E. Byrd ◽

D. Alsheh ◽

W. McDonough ◽

J. Seiler

Keyword(s):

Polymer Coating ◽

Peel Test ◽

Water Layer ◽

Fiber Composites ◽

Polymer Coatings ◽

Interfacial Water ◽

Glass Fiber Composites ◽

Mir Spectroscopy ◽

Water Adhesion ◽

Interlaminar Shear

ABSTRACTWater is often the main cause of adhesion loss of a polymer coating/substrate system. The buildup of the interfacial water layer and the loss of adhesion of polymer-coated siliceous substrates exposed to liquid water has been investigated. The thickness of the interfacial water layer was measured on epoxy-coated SiO2-Si prisms using FTIR-multiple internal reflection (FTIR-MIR) spectroscopy. Adhesion loss on flat siliceous substrates was determined by a wet peel test on epoxy-coated SiO2-Si wafers and adhesion loss of composites was obtained by measuring the interlaminar shear strengths of epoxy/E-glass fiber composites. Both untreated and 0.1 % silane-treated substrates were used. Little water was observed at the interface of the silanetreated samples but about 10 monolayers of water have accumulated at the interface of the untreated samples after 100 h of exposure to 24°C water. Untreated, flat substrates lost most of their bonding strengths within 75 h of exposure but silane-treated specimens retained 80% of their adhesion after 600 h of exposure to 24°C water. Adhesion loss of untreated composites immersed in 60°C water was greater than that of treated samples; however, the rate of loss of both silanetreated and untreated composites was much lower than that of flat substrates. Adhesion loss was found to follow the same trend as interfacial water buildup.

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