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Article
Publication date: 12 November 2021

Mohammed Amin Rabah and Bekhti Mohammed

The present work aims to analyze the performance of a newly designed graphene-based patch antenna by varying the chemical potential in graphene sheet, using the CST…

Abstract

Purpose

The present work aims to analyze the performance of a newly designed graphene-based patch antenna by varying the chemical potential in graphene sheet, using the CST Microwave Studio ® software. This study mainly seeks to discuss and assess the advantage of using graphene, instead of copper, as the radiating patch. It should be noted that graphene is a new material that possesses unique properties. Its parameters are optimized for the purpose of introducing it in satellite technology.

Design/methodology/approach

The use of graphene as a radiating patch of space technology applications, where a polygonal graphene patch antenna element is designed by the CST Microwave Studio ® software with Taconic RF-41 substrate to resonate in the satellite bands.

Findings

Analysis of a graphene patch sheet by a variation in the chemical potential to ensure operation in a space environment.

Originality/value

The increase in the chemical potential for a graphene patch antenna has shown a prominent increase in the values of the gain. A new contribution, by the combination of the antenna performance improvement techniques and the use of graphene as a radiating patch of space technology applications.

Details

Aircraft Engineering and Aerospace Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 30 June 2021

Hui Li, Zengwen Zhang, Ruiyang Fang, Zhihui Gao and Wei He

The authors designed those experiments to test the sensitivity of graphene when it is exposed to NO2 gas, to find a way to decrease the recovery time of graphene and to…

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Abstract

Purpose

The authors designed those experiments to test the sensitivity of graphene when it is exposed to NO2 gas, to find a way to decrease the recovery time of graphene and to find the difference effect between monolayer and bilayer graphene in the experiments.

Design/methodology/approach

The authors transferred graphene from film on Cu foil to NO2 sensor sample and measured the resistances of on monolayer and bilayer graphene when they were exposed to NO2 gas under different concentration; then, the authors obtained the results.

Findings

The results show that monolayer graphene exhibits a linear response when the NO2 concentration is below 20 ppm. But the monolayer graphene will not be so sensitive to NO2 gas when the concentration continues to reduce. The desorption time of monolayer graphene is longer when compared with bilayer graphene. It shows faster recovery time and higher response of bilayer graphene under low NO2 concentration. And the limit detectable NO2 concentration of bilayer graphene is 50 ppb. Desorption time of bilayer graphene is shortened to below 20 s under UV light.

Originality/value

The authors found a reliable way to decrease the recovery time of graphene when it is exposed NO2 gas and got the concrete data.

Details

Sensor Review, vol. 41 no. 3
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 10 January 2020

Yong Qian, Hongying Gong, Xiaoyun Zhao, Lei Cao, Weizhong Shi and Jianli He

The purpose of this study is to corroborate the advanced tribological properties of graphene as a lubricant additive.

Abstract

Purpose

The purpose of this study is to corroborate the advanced tribological properties of graphene as a lubricant additive.

Design/methodology/approach

Different concentrations of functionalized graphene were coated on the substrate surface. Tribological properties of the graphene lubricants were carried out by ball-on-disk tribology tests. Wear mechanism of functionalized graphene was studied by observing wear scars on the substrate surface. Finally, the wear resistance of modified graphene was calculated by calculating and analyzing the applied experimental conditions and the obtained experimental data.

Findings

The best concentration of graphene lubricant is 0.5 wt.% which shows the best tribological performance. And the coefficient of friction is 0.08. Compared with the dry friction condition, the coefficient of friction and wear rate of best graphene lubricant decreased by 80% and 82%.

Originality/value

The formula of graphene lubricant is independently developed and works very well. Graphene lubricant can prevent the substrate from oxidation. The thickness of the graphene lubricant is about 4-7µm. The concept of anti-wear strength was introduced in this paper. When 0.5 Vol.% graphene was added, the anti-wear strength was greatly improved from 115.3 kg·mm-2 to 657.6 kg·mm-2.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2019-0344

Details

Industrial Lubrication and Tribology, vol. 72 no. 3
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 10 June 2014

Robert Bogue

– This paper aims to provide details of recent developments in nanosensors based on graphene.

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Abstract

Purpose

This paper aims to provide details of recent developments in nanosensors based on graphene.

Design/methodology/approach

Following an introduction, this paper first considers some of the motivations for using graphene in sensors. It then describes a selection of recently reported graphene nanosensors for detecting physical variables, gases, chemical species and biological agents. Finally, brief conclusions are drawn.

Findings

Graphene exhibits a number of unique properties that make it an intriguing candidate for use in sensors. Research is still at a relatively early stage, but prototype sensors have been demonstrated which respond to numerous physical, molecular and biological variables.

Originality/value

This paper provides a timely review of the use of graphene in sensors.

Details

Sensor Review, vol. 34 no. 3
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 7 October 2021

Amrita Maddamasetty, Kamesh Bodduru, Siva Bevara, Rukmini Srikant Revuru and Sanjay Kumar

Inconel 718 is difficult to machine due to its high toughness and study hardenability. Though the use of cutting fluids alleviates the problem, it is not sustainable. So…

Abstract

Purpose

Inconel 718 is difficult to machine due to its high toughness and study hardenability. Though the use of cutting fluids alleviates the problem, it is not sustainable. So, supply of a small quantity of specialized coolant to the machining zone or use of a solid lubricant is a possible solution. The purpose of the present work is to improve machinability of Inconel718 using graphene nanoplatelets.

Design/methodology/approach

In the present study, graphene is used in the machining of Inconel 718 alloy. Graphene is applied in the following two forms: as a solid lubricant and as an inclusion in cutting fluid. Graphene-based self-lubricating tool and graphene added nanofluids are prepared and applied to turning of Inconel 718 at varying cutting velocities. Performances are compared by measuring cutting forces, cutting temperature, tool wear and surface roughness.

Findings

Graphene, in both forms, showed superior performance compared to dry machining. In total, 0.3 Wt.% graphene added nanofluids showed the lowest cutting tool temperature and flank wear with 44.95% and 83.37% decrease, respectively, compared to dry machining and lowest surface roughness, 0.424 times compared to dry machining at 87 m/min.

Originality/value

Graphene could improve the machinability of Inconel 718 when used in tools as a solid lubricant and also when used as a dispersant in cutting fluid. Graphene used as a dispersant in cutting fluid is found to be more effective.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 7 August 2021

Vijay Kumar Dwivedi and Dipak Kumar

The purpose of this paper is related with the comparative study between graphene-based glass fiber–reinforced polymer composites and without graphene composite on polymer…

Abstract

Purpose

The purpose of this paper is related with the comparative study between graphene-based glass fiber–reinforced polymer composites and without graphene composite on polymer matrix. The current study explains the result of amalgamation of 4 Wt.% graphene oxide (GO), in comparison to without graphene, on the mechanical strength of glass fiber/epoxy (GE).

Design/methodology/approach

A hand layup technique is used for the experimental study. For this, chemical synthesis process is approached based on Hummer’s theory. For mechanical testing of glass fiber–reinforced graphene composites and without graphene composites, American Society for Testing and Materials-3039 (ASTM3039) standards was adopted. Furthermore, comparatively, composites were characterized by field emission scanning electron microscopy.

Findings

Reinforcement of 4.0 Wt.% GO in epoxy matrix material showed 7.46% and 12.31% improvement in mechanical strength and elongation, respectively. Scanning electron microscopy results showed the influence of graphene cumulations in the failure of GO-reinforced GE (GO-GE) composites.

Originality/value

The inimitable things of graphene grounded nanofillers have encouraged in the world of material for their thinkable manipulation in glass fiber polymeric composites. In this work, for the first time, graphene is used as nanofiller in glass fiber epoxy coatings, and their fractography study is investigated.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 12 August 2021

Amrita M., Rukmini Srikant Revuru, Sreeram Chatti, Sree Satya Bharati Sri Satya Moram, Chandu Byram and Venugopal Rao Soma

Ti6Al4V is a commonly used titanium alloy with several applications in aerospace industry due to its excellent strength to weight ratio. But due to low thermal…

Abstract

Purpose

Ti6Al4V is a commonly used titanium alloy with several applications in aerospace industry due to its excellent strength to weight ratio. But due to low thermal conductivity, it is categorized as “difficult to machine.” Though machinability can be improved with cutting fluids, it is not preferred due to associated problems. This study aims at eliminating the use of cutting fluid and finding an alternate solution to dry machining of Ti6Al4V. AlTiN coated tools provide good heat and oxidation resistance but have low lubricity. In the present work, graphene, which is known for lubricating properties, is added to the tools using five different methods (tool condition) to form graphene self-lubricated cutting tools.

Design/methodology/approach

Graphene-based self-lubricating tools are prepared by using five methods: dip coating (10 dips and 30 dips); drop casting; and filling of micro/macroholes. Performance of these tools is evaluated in terms of cutting forces, surface roughness and tool wear by machining Ti6Al4V and comparing with conventional coated cutting tool.

Findings

Self-lubricating tool with micro holes filled with graphene outperformed other tools and showed maximum decrease of 33.42% in resultant cutting forces, 35% in surface roughness (Ra) and 30% in flank wear compared to conventional cutting tool.

Originality/value

Analysis of variance for all forces show that tool condition and machining time have significant influence on all components of cutting forces and resultant cutting forces.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 6 July 2021

Jing Wang, Hongying Mi, Weigui Zhou, Xin Yang and Yan He

This study aims to the preparation and tribological characteristics of graphene/triangular copper nanoplate composites (abbreviated as GN/Cu nanoplates) as grease additive…

Abstract

Purpose

This study aims to the preparation and tribological characteristics of graphene/triangular copper nanoplate composites (abbreviated as GN/Cu nanoplates) as grease additive and clarifies the growth mechanism and tribological mechanism of GN/Cu nanoplates by different analysis methods. In this paper, it is expected to alleviate the problems of easy aggregation and poor dispersion stability of graphene in lubricants and provide theoretical support for the application of graphene and its composites in the tribology field.

Design/methodology/approach

In this study, the GN/Cu nanoplates have been successfully prepared by the electrostatic self-assembly method. The structural characteristics of GN/Cu nanoplates were analyzed via transmission electron microscopy and X-ray diffraction. Then the tribological properties of GN/Cu nanoplates were investigated under different loads with SRV-IV [Schwingung, Reibung, Verschleiß (German); oscillating, friction, wear (English translation)] tribotester. White-light interferometry was applied to quantify the wear loss of the disk. The element chemical state on worn surfaces was analyzed by an X-ray photoelectron spectroscope to clarify the tribological mechanism of graphene composites.

Findings

The electrostatic force between the negative charge of graphene and the positive charge of triangular copper nanoplates promotes the self-assembly of GN/Cu nanoplates. With the addition of GN/Cu nanoplates, the wear loss and average friction coefficient under the load of 200 N have been decreased by 72.6% and 18.3%, respectively. It is concluded that the combined action of graphene deposition film and the copper melting film formed on the worn surface could effectively improve the antiwear ability and friction reduction performance of the grease.

Originality/value

This manuscript fulfills a new approach for the preparation of GN/Cu nanoplates. At the same time, its tribological properties and mechanism as a lubricating additive were studied which provide theoretical support for the application of graphene and its composites in the tribology field.

Details

Industrial Lubrication and Tribology, vol. 73 no. 5
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 14 December 2020

Raed Salman Saeed Alhusseini, Ali Sadik Gafer Qanber, Bashar Dheyaa Hussein Al-Kasob, Manar Hamid Jasim and Mehdi Ranjbar

This paper aims to present the potential of using aligned single-layer graphene sheets to reinforce the methyl methacrylate cantilever beam in low-velocity impact problem.

Abstract

Purpose

This paper aims to present the potential of using aligned single-layer graphene sheets to reinforce the methyl methacrylate cantilever beam in low-velocity impact problem.

Design/methodology/approach

The Halpin–Tsai law is applied to compute the mechanical properties of isotropic polymer beam reinforced by aligned graphene sheet. Using both longitudinal and lateral displacements in composite beam, all components of the stress and strain fields are written. The equations of motion are derived by applying energy method, generalized Lagrange equations and Ritz method.

Findings

The analytical formulation accuracy is corroborated by comparing the present results with those available in the literature. Numerical examples indicate that the contact duration is decreased with increasing of graphene volume fraction, whereas the values of peak contact force, shear strain and shear stress at peak contact force tend to be vice versa. Also, among the results, shear stress at the peak contact force has the most effect with graphene volume fraction changes.

Originality/value

This research fulfils an identified need to investigate how graphene-reinforced beam behavior subjected to low-velocity impact can be enabled.

Details

World Journal of Engineering, vol. 18 no. 3
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 30 March 2020

Gurminder Singh and Pulak Mohan Pandey

The purpose of this study is to study the mechanical, tribological and electrical properties of the copper-graphene (Cu-Gn) composites fabricated by a novel rapid tooling…

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Abstract

Purpose

The purpose of this study is to study the mechanical, tribological and electrical properties of the copper-graphene (Cu-Gn) composites fabricated by a novel rapid tooling technique consist of three-dimensional printing and ultrasonic-assisted pressureless sintering (UAPS).

Design/methodology/approach

Four different Cu-Gn compositions with 0.25, 0.5, 1 and 1.5 per cent of graphene were fabricated using an amalgamation of three-dimensional printing and UAPS. The polymer 3d printed parts were used to prepare mould cavity and later the UAPS process was used to sinter Cu-Gn powder to acquire free-form shape. The density, hardness, wear rate, coefficient of friction and electrical conductivity were evaluated for the different compositions of graphene and compared with the pure copper. Besides, the comparison was performed with the conventional method.

Findings

Cu-Gn composites revealed excellent wear properties due to higher hardness, and the lubrication provided by the graphene. The electrical conductivity of the fabricated Cu-Gn composites started increasing initially but decreased afterwards with increasing the content of graphene. The UAPS fabricated composites outperformed the conventional method manufactured samples with better properties such as density, hardness, wear rate, coefficient of friction and electrical conductivity due to homogeneous mixing of metal particles and graphene.

Originality/value

The fabrication of Cu-Gn composite freeform shapes was found to be difficult using conventional methods. The novel technique using a combination of polymer three-dimensional printing and UAPS as rapid tooling was introduced for the fabrication of freeform shapes of Cu-Gn composites and mechanical, tribological and electrical properties were studied. The method can be used to fabricate optimized complex Cu-Gn structures with improved wear and electrical applications.

Details

Rapid Prototyping Journal, vol. 26 no. 4
Type: Research Article
ISSN: 1355-2546

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