Investigation of knitting architecture on the impact behavior of glass/epoxy composites

Hydrophobic surfaces are highly desired for several applications due to their exceptional properties such as self-cleaning, anti-icing, anti-friction and others. Such surfaces can be prepared via numerous methods including plasma technology, a dry technique with low environmental impact. In this paper, the effect of a one-step sulfur hexafluoride (SF6) plasma treatment upon the low velocity impact behavior of basalt/epoxy composites has been investigated by using several characterization techniques. A capacitive coupled radiofrequency plasma system was used for the plasma surface treatment of basalt/epoxy composites, and suitable surface treatment conditions were experimentally investigated with respect to gas flow rate, chamber pressure, power intensity, and surface treatment time by measuring the water droplet contact angle of treated specimens. The contact angle measurements showed that treating with SF6 plasma would increase the hydrophobicity of basalt/epoxy composites; moreover, the impact results obtained on reinforced epoxy basalt fiber showed damage in a confined area and higher impact resistance for plasma-treated basalt systems.

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

Processes ◽

10.3390/pr9050738 ◽

2021 ◽

Vol 9 (5) ◽

pp. 738

Author(s):

Kamila Sałasińska ◽

Mikelis Kirpluks ◽

Peteris Cabulis ◽

Andrejs Kovalovs ◽

Eduard Skukis ◽

...

Keyword(s):

Mechanical Properties ◽

Hybrid Composites ◽

Fire Behavior ◽

Epoxy Composites ◽

Impact Behavior ◽

Cone Calorimetry ◽

Burning Behavior ◽

Different Types ◽

Flexural Tests ◽

The Impact

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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Effect of Plasma Surface Treatment on the Impact Behavior of Basalt/Epoxy Composites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.813.441 ◽

2019 ◽

Vol 813 ◽

pp. 441-446

Author(s):

Maria Rosaria Ricciardi ◽

Ilaria Papa ◽

Giuseppe Coppola ◽

Filomena Impero ◽

Valentina Lopresto ◽

...

Keyword(s):

Surface Treatment ◽

Plasma Treatment ◽

Composite Laminates ◽

Atmospheric Oxygen ◽

Epoxy Composites ◽

Low Velocity Impact ◽

Impact Behavior ◽

Low Velocity ◽

Composite Surface ◽

The Impact

In this study, the effects of surface treatment of a low-temperature atmospheric oxygen plasma on basalt/epoxy composites were investigated to improve the hydrophobility of the composite surface. After the plasma treatment, the unmodified and surface treated composite laminates have been experimentally characterized by performing contact angle measurements, low-velocity impact tests and indentation depth on the impacted laminates. Results have showed a dependence of such composite properties on the plasma coating deposition and on the treatment parameters outlining the need to optimize both the plasma power and exposition time to plasma in order to assess the efficiency of the plasma treatment and establish the optimal processing conditions.

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Effect of extreme cold temperatures on quasi-static indentation and impact behavior of woven carbon fiber epoxy composite sandwich panels with nomex honeycomb core

Journal of Sandwich Structures & Materials ◽

10.1177/1099636221993876 ◽

2021 ◽

pp. 109963622199387

Author(s):

Mathilde Jean-St-Laurent ◽

Marie-Laure Dano ◽

Marie-Josée Potvin

Keyword(s):

Epoxy Composite ◽

Impact Behavior ◽

Effect Of Temperature ◽

Cold Temperatures ◽

Composite Sandwich Panels ◽

Composite Sandwich ◽

Static Indentation ◽

Nomex Honeycomb ◽

Extreme Cold ◽

The Impact

The effect of extreme cold temperatures on the quasi-static indentation and the low velocity impact behavior of woven carbon/epoxy composite sandwich panels with Nomex honeycomb core was investigated. Impact tests were performed at room temperature, –70°C, and –150°C. Two sizes of hemispherical impactor were used combined to three different impactor masses. All the impact tests were performed at the same initial impact velocity. The effect of temperature on the impact behavior is investigated by studying the load history, load-displacement curves and transmitted energy as a function of time curves. Impact damage induced at various temperatures was studied using different non-destructive and destructive techniques. Globally, more damages are induced with impact temperature decreasing. The results also show that the effect of temperature on the impact behavior is function of the impactor size.

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Effect of the plastic hinge and boundary conditions on the impact behavior of reinforced concrete beams

International Journal of Impact Engineering ◽

10.1016/j.ijimpeng.2016.12.005 ◽

2017 ◽

Vol 102 ◽

pp. 74-85 ◽

Cited By ~ 43

Author(s):

Thong M. Pham ◽

Hong Hao

Keyword(s):

Reinforced Concrete ◽

Boundary Conditions ◽

Concrete Beams ◽

Plastic Hinge ◽

Reinforced Concrete Beams ◽

Impact Behavior ◽

The Impact

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Impact Resistance of Epoxy Composites Reinforced with Amazon Guaruman Fiber: A Brief Report

Polymers ◽

10.3390/polym13142264 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2264

Author(s):

Raphael H. M. Reis ◽

Fabio C. Garcia Filho ◽

Larissa F. Nunes ◽

Veronica S. Candido ◽

Alisson C. R. Silva ◽

...

Keyword(s):

Fiber Composite ◽

Impact Resistance ◽

Fiber Composites ◽

Epoxy Composites ◽

Impact Performance ◽

Electron Microscopy Analysis ◽

Ballistic Properties ◽

Microscopy Analysis ◽

Izod Impact ◽

The Impact

Fibers extracted from Amazonian plants that have traditionally been used by local communities to produce simple items such as ropes, nets, and rugs, are now recognized as promising composite reinforcements. This is the case for guaruman (Ischinosiphon körn) fiber, which was recently found to present potential mechanical and ballistic properties as 30 vol% reinforcement of epoxy composites. To complement these properties, Izod impact tests are now communicated in this brief report for similar composites with up to 30 vol% of guaruman fibers. A substantial increase in impact resistance, with over than 20 times the absorbed energy for the 30 vol% guaruman fiber composite, was obtained in comparison to neat epoxy. These results were statistically validated by Weibull analysis, ANOVA, and Tukey’s test. Scanning electron microscopy analysis disclosed the mechanisms responsible for the impact performance of the guaruman fiber composites.

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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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