Experimental Investigation of the Mechanical Properties and Fire Behavior of Epoxy Composites Reinforced by Fabrics and Powder Fillers

Different types of fabrics, such as aramid (A), carbon (C), basalt (B), glass (G), and flax (F), as well as powder fillers, were used to manufacture the epoxy-based hybrid composites by the hand-lay-up method. In this work, a few research methods, including hardness, flexural tests, puncture impact behavior, as well as cone calorimetry (CC) measurements, were applied to determine the impact of type fillers and order of fabrics on the performance and burning behavior of hybrid composites. The mechanical properties were evaluated to correlate with the microstructure and consider together with thermogravimetric analysis (TGA) data.

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The Effect of Manufacture Process on Mechanical Properties and Burning Behavior of Epoxy-Based Hybrid Composites

Materials ◽

10.3390/ma15010301 ◽

2022 ◽

Vol 15 (1) ◽

pp. 301

Author(s):

Kamila Sałasińska ◽

Peteris Cabulis ◽

Mikelis Kirpluks ◽

Andrejs Kovalovs ◽

Paweł Kozikowski ◽

...

Keyword(s):

Mechanical Properties ◽

Hybrid Composites ◽

Fire Behavior ◽

Impact Behavior ◽

Layered Composites ◽

Cone Calorimetry ◽

Smoke Emission ◽

Manufacturing Method ◽

Burning Behavior ◽

Manufacture Process

The production of hybrid layered composites allows comprehensive modification of their properties and adaptation to the final expectations. Different methods, such as hand lay-up, vacuum bagging, and resin infusion were applied to manufacture the hybrid composites. In turn, fabrics used for manufacturing composites were made of glass (G), aramid (A), carbon (C), basalt (B), and flax (F) fibers. Flexural, puncture impact behavior, and cone calorimetry tests were applied to establish the effect of the manufacturing method and the fabrics layout on the mechanical and fire behavior of epoxy-based laminates. The lowest flammability and smoke emission were noted for composites made by vacuum bagging (approximately 40% lower values of total smoke release compared with composites made by the hand lay-up method). It was demonstrated that multi-layer hybrid composites made by vacuum bagging might enhance the fire safety levels and simultaneously maintain high mechanical properties designed for, e.g., the railway and automotive industries.

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Effect of toughened polyamide-coated carbon fiber fabric on the mechanical performance and fracture toughness of CFRP

Journal of Composite Materials ◽

10.1177/0021998321999458 ◽

2021 ◽

pp. 002199832199945

Author(s):

Jong H Eun ◽

Bo K Choi ◽

Sun M Sung ◽

Min S Kim ◽

Joon S Lee

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Photoelectron Spectroscopy ◽

Mechanical Performance ◽

Epoxy Composites ◽

Scanning Calorimetry ◽

Internal Damage ◽

Impact Tests ◽

Flexural Tests ◽

The Impact

In this study, carbon/epoxy composites were manufactured by coating with a polyamide at different weight percentages (5 wt.%, 10 wt.%, 15 wt.%, and 20 wt.%) to improve their impact resistance and fracture toughness. The chemical reaction between the polyamide and epoxy resin were examined by fourier transform infrared spectroscopy, differential scanning calorimetry and X-ray photoelectron spectroscopy. The mechanical properties and fracture toughness of the carbon/epoxy composites were analyzed. The mechanical properties of the carbon/epoxy composites, such as transverse flexural tests, longitudinal flexural tests, and impact tests, were investigated. After the impact tests, an ultrasonic C-scan was performed to reveal the internal damage area. The interlaminar fracture toughness of the carbon/epoxy composites was measured using a mode I test. The critical energy release rates were increased by 77% compared to the virgin carbon/epoxy composites. The surface morphology of the fractured surface was observed. The toughening mechanism of the carbon/epoxy composites was suggested based on the confirmed experimental data.

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Basalt Fiber-Based Flame Retardant Epoxy Composites: Preparation, Thermal Properties, and Flame Retardancy

Materials ◽

10.3390/ma14040902 ◽

2021 ◽

Vol 14 (4) ◽

pp. 902

Author(s):

Yu Guo ◽

Meihui Zhou ◽

Guang-Zhong Yin ◽

Ehsan Kalali ◽

Na Wang ◽

...

Keyword(s):

Mechanical Properties ◽

Thermal Properties ◽

Flame Retardant ◽

Basalt Fiber ◽

Mechanical Analysis ◽

Epoxy Composites ◽

Cone Calorimetry ◽

Limiting Oxygen Index ◽

Pre Treatment ◽

The Impact

We aimed to study the impact of surface modification of basalt fiber (BF) on the mechanical properties of basalt fiber-based epoxy composites. Four different types of pretreatment approaches to BF were used; then a silane coupling agent (KH550) was applied to further modify the pretreated BF, prior to the preparation of epoxy resin (EP)/BF composites. The combination of acetone (pre-treatment) and KH550 (formal surface treatment) for basalt fiber (BT-AT) imparted the EP/BF composite with the best performance in both tensile and impact strengths. Subsequently, such modified BF was introduced into the flame-retardant epoxy composites (EP/AP750) to prepare basalt fiber reinforced flame-retardant epoxy composite (EP/AP750/BF-AT). The fire behaviors of the composites were evaluated by vertical burning test (UL-94), limiting oxygen index (LOI) test and cone calorimetry. In comparison to the flame-retardant properties of EP/AP750, the incorporation of BF-AT slightly reduced LOI value from 26.3% to 25.1%, maintained the good performance in vertical burning test, but increased the peak of the heat release rate. Besides, the thermal properties and mechanical properties of the composites were investigated by thermogravimetric analysis (TGA), universal tensile test, impact test and dynamic mechanical analysis (DMA).

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Effects of Hydrothermal Seawater Aging on the Mechanical Properties and Water Absorption of Glass/Aramid/Epoxy Hybrid Composites

International Polymer Processing ◽

10.1515/ipp-2020-3963 ◽

2021 ◽

Vol 36 (1) ◽

pp. 79-93

Author(s):

Z. A. Oğuz ◽

A. Erkliğ ◽

Ö. Y. Bozkurt

Keyword(s):

Mechanical Properties ◽

Flexural Strength ◽

Hybrid Composites ◽

Mechanical Tests ◽

Low Velocity Impact ◽

Impact Behavior ◽

Hydrothermal Aging ◽

Charpy Test ◽

Matrix Cracks ◽

The Impact

Abstract With the increase in the diversity of applications, the effect of environmental conditions on the mechanical properties of polymeric composites have become more valuable due to the sensitivity of polymers to aging. In this study, an experimental investigation was carried out to study the seawater aging effect on the flexural and low-velocity impact behavior of glass/aramid/ epoxy hybrid composites. Four types of composite groups that are [G6]S, [A6]S, [G3A3]S, [A3G3]S manufactured by vacuum infusion method were immersed in seawater at 25 °C and 70°C for 1000 h. Mechanical tests were conducted under three different conditions, namely, dry, wet, re-dried. As temperature increases, the water gain ratio also increases for all composite groups. Flexural strength was significantly reduced with seawater absorption for the wet state tested groups at each temperature. The reductions in flexural strength of the re-dried test groups are less than in the wet state test samples. Charpy test results showed that as the composite groups were exposed to hydrothermal aging, the impact strength of the plain glass/ epoxy, GAG/epoxy, and AGA/epoxy hybrid composite decreased. SEM analysis showed that as temperature increases, delamination and fiber/matrix cracks also increases.

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Effect of Secondary Carbon Nanofillers on the Electrical, Thermal, and Mechanical Properties of Conductive Hybrid Composites Based on Epoxy Resin and Graphite

Materials ◽

10.3390/ma14154169 ◽

2021 ◽

Vol 14 (15) ◽

pp. 4169

Author(s):

Marcel Zambrzycki ◽

Krystian Sokolowski ◽

Maciej Gubernat ◽

Aneta Fraczek-Szczypta

Keyword(s):

Mechanical Properties ◽

Specific Surface ◽

Epoxy Resin ◽

Surface Area ◽

Specific Surface Area ◽

Hybrid Composites ◽

Department Of Energy ◽

Carbon Nanofillers ◽

The Impact ◽

Secondary Carbon

In this work, we present a comparative study of the impact of secondary carbon nanofillers on the electrical and thermal conductivity, thermal stability, and mechanical properties of hybrid conductive polymer composites (CPC) based on high loadings of synthetic graphite and epoxy resin. Two different carbon nanofillers were chosen for the investigation—low-cost multi-layered graphene nanoplatelets (GN) and carbon black (CB), which were aimed at improving the overall performance of composites. The samples were obtained by a simple, inexpensive, and effective compression molding technique, and were investigated by the means of, i.a., scanning electron microscopy, Raman spectroscopy, electrical conductivity measurements, laser flash analysis, and thermogravimetry. The tests performed revealed that, due to the exceptional electronic transport properties of GN, its relatively low specific surface area, good aspect ratio, and nanometric sizes of particles, a notable improvement in the overall characteristics of the composites (best results for 4 wt % of GN; σ = 266.7 S cm−1; λ = 40.6 W mK−1; fl. strength = 40.1 MPa). In turn, the addition of CB resulted in a limited improvement in mechanical properties, and a deterioration in electrical and thermal properties, mainly due to the too high specific surface area of this nanofiller. The results obtained were compared with US Department of Energy recommendations regarding properties of materials for bipolar plates in fuel cells. As shown, the materials developed significantly exceed the recommended values of the majority of the most important parameters, indicating high potential application of the composites obtained.

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COMPUTATIONAL MODELING OF EPOXY-BASED HYBRID COMPOSITES REINFORCED WITH CARBON FIBERS AND FUNCTIONALIZED GRAPHENE NANOPLATELETS

10.12783/asc36/35846 ◽

2021 ◽

Author(s):

HASHIM AL MAHMUD ◽

, MATTHEW RADUE ◽

WILLIAM PISANI ◽

GREGORY ODEGARD

Keyword(s):

Mechanical Properties ◽

Graphene Oxide ◽

Hybrid Composites ◽

Graphene Nanoplatelets ◽

Pristine Graphene ◽

Functionalized Graphene ◽

Functionalized Graphene Oxide ◽

Aspect Ratios ◽

The Impact ◽

Nanoscale Level

The impact on the mechanical properties of unidirectional carbon fiber (CF)/epoxy composites reinforced with pristine graphene nanoplatelets (GNP), highly concentrated graphene oxide (GO), and Functionalized Graphene Oxide (FGO) are investigated in this study. The localized reinforcing effect of each of the graphene nanoplatelet types on the epoxy matrix is predicted at the nanoscale-level by molecular dynamics. The bulk-level mechanical properties of unidirectional CF/epoxy hybrid composites are predicted using micromechanics techniques considering the reinforcing function, content, and aspect ratios for each of the graphene nanoplatelets. In addition, the effect of nanoplatelets dispersion level is also investigated for the pristine graphene nanoplatelets considering a lower dispersion level with four layers of graphene nanoplatelets (4GNP). The results indicate that the shear and transverse properties are significantly affected by the nanoplatelet type, loading and aspect ratio. The results of this study can be used in the design of hybrid composites to tailor specific laminate properties by adjusting nanoplatelet parameters.

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Effect of Filler Compositions on the Mechanical Properties of Bamboo Filled Polyester Composite

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.879.90 ◽

2014 ◽

Vol 879 ◽

pp. 90-95 ◽

Cited By ~ 2

Author(s):

Abdul Rahman Noor Leha ◽

Nor Amalina Nordin

Keyword(s):

Mechanical Properties ◽

Flexural Strength ◽

Impact Test ◽

Compression Molding ◽

Engineering Applications ◽

Maximum Value ◽

Polyester Composite ◽

Bamboo Powder ◽

Flexural Tests ◽

The Impact

Biocomposite from bamboo powder was fabricated by compression molding technique. The objective of this study was to investigate the mechanical properties of bamboo compounded with epoxy with different ratio. Tensile and flexural tests were done to characterize its mechanical properties. It was observed that the strength of bamboo-polyester was increased with increasing amount of bamboo powder. The tensile and flexural strength shows the highest value at 25 wt.% bamboo. However, the impact test shows the maximum value at 20 wt.% bamboo powder. These results exhibit the bamboo-polyester can be a good candidate to be used in many engineering applications

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Influence of layering pattern of modified kenaf fiber on thermomechanical properties of epoxy composites

Progress in Rubber Plastics and Recycling Technology ◽

10.1177/1477760619895010 ◽

2019 ◽

Vol 36 (1) ◽

pp. 47-62

Author(s):

AR Mohammed ◽

MS Nurul Atiqah ◽

Deepu A Gopakumar ◽

MR Fazita ◽

Samsul Rizal ◽

...

Keyword(s):

Mechanical Properties ◽

Chemical Modification ◽

Epoxy Matrix ◽

Epoxy Composites ◽

Woven Composites ◽

Fiber Reinforced ◽

Kenaf Fiber ◽

Kenaf Fibers ◽

The Impact ◽

Woven Kenaf

Natural fiber-reinforced composites gained considerable interest in the scientific community due to their eco-friendly nature, cost-effective, and excellent mechanical properties. Here, we reported a chemical modification of kenaf fiber using propionic anhydride to enhance the compatibility with the epoxy matrix. The incorporation of the modified woven and nonwoven kenaf fibers into the epoxy matrix resulted in the improvement of the thermal and mechanical properties of the composite. The thermal stability of the epoxy composites was enhanced from 403°C to 677°C by incorporating modified woven kenaf fibers into the epoxy matrix. The modified and unmodified woven kenaf fiber-reinforced epoxy composites had a tensile strength of 64.11 and 58.82 MPa, respectively. The modified woven composites had highest flexural strength, which was 89.4 MPa, whereas, for unmodified composites, it was 86.8 MPa. The modified woven fiber-reinforced epoxy composites showed the highest value of flexural modulus, which was 6.0 GPa compared to unmodified woven composites (5.51 GPa). The impact strength of the epoxy composites was enhanced to 9.43 kJ m−2 by the incarnation of modified woven kenaf fibers into epoxy matrix. This study will be an effective platform to design the chemical modification strategy on natural fibers for enhancing the compatibility toward the hydrophobic polymer matrices.

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Dynamic Mechanical Properties of Hybrid Layered Silicates/Kaolin Geopolymer Filler in Epoxy Composites

Materiale Plastice ◽

10.37358/mp.17.3.4891 ◽

2017 ◽

Vol 54 (3) ◽

pp. 543-545 ◽

Cited By ~ 4

Author(s):

Yusrina Mat Daud ◽

Kamarudin Hussin ◽

Azlin Fazlina Osman ◽

Che Mohd Ruzaidi Ghazali ◽

Mohd Mustafa Al Bakri Abdullah ◽

...

Keyword(s):

Mechanical Properties ◽

High Speed ◽

Hybrid Composites ◽

Loss Modulus ◽

Dynamic Mechanical Properties ◽

Mechanical Analysis ◽

Layered Silicates ◽

Epoxy Composites ◽

Damping Factor ◽

Dynamic Mechanical

Preparation epoxy based hybrid composites were involved kaolin geopolymer filler, organo-montmorillonite at 3phr by using high speed mechanical stirrer. A mechanical behaviour of neat epoxy, epoxy/organo-montmorillonite and its hybrid composites containing 1-8phr kaolin geopolymer filler was studied upon cyclic deformation (three-point flexion mode) as the temperature is varies. The analysis was determined by dynamic mechanical analysis (DMA) at frequency of 1.0Hz. The results then expressed in storage modulus (E�), loss modulus (E�) and damping factor (tan d) as function of temperature from 40 oC to 130oC. Overall results indicated that E�, E�� and Tg increased considerably by incorporating optimum 1phr kaolin geopolymer in epoxy organo-montmorillonite hybrid composites.

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Mechanical Performance of Unstitched and Silk Fiber-Stitched Woven Kenaf Fiber-Reinforced Epoxy Composites

Materials ◽

10.3390/ma13214801 ◽

2020 ◽

Vol 13 (21) ◽

pp. 4801

Author(s):

Yasir Khaleel Kirmasha ◽

Mohaiman J. Sharba ◽

Zulkiflle Leman ◽

Mohamed Thariq Hameed Sultan

Keyword(s):

Mechanical Properties ◽

Flexural Strength ◽

Mechanical Performance ◽

Mechanical Test ◽

Natural Fibers ◽

Silk Fiber ◽

Epoxy Composites ◽

Test Results ◽

The Impact ◽

Woven Kenaf

Fiber composites are known to have poor through-thickness mechanical properties due to the absence of a Z-direction binder. This issue is more critical with the use of natural fibers due to their low strength compared to synthetic fibers. Stitching is a through-thickness toughening method that is used to introduce fibers in the Z-direction, which will result in better through-thickness mechanical properties. This research was carried out to determine the mechanical properties of unstitched and silk fiber-stitched woven kenaf-reinforced epoxy composites. The woven kenaf mat was stitched with silk fiber using a commercial sewing machine. The specimens were fabricated using a hand lay-up method. Three specimens were fabricated, one unstitched and two silk-stitched with deferent stitching orientations. The results show that the stitched specimens have comparable in-plane mechanical properties to the unstitched specimens. For the tensile mechanical test, stitched specimens show similar and 17.1% higher tensile strength compared to the unstitched specimens. The flexural mechanical test results show around a 9% decrease in the flexural strength for the stitched specimens. On the other hand, the Izod impact mechanical test results show a significant improvement of 33% for the stitched specimens, which means that stitching has successfully improved the out-of-plane mechanical properties. The outcome of this research indicates that the stitched specimens have better mechanical performance compared to the unstitched specimens and that the decrease in the flexural strength is insignificant in contrast with the remarkable enhancement in the impact strength.

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