Addition Of Graphene Nanosheets Research Articles

Unravelling the synergistic enhancement effect of Ag3Sn phase and graphene nanosheets addition on the thermal cycling reliability of Sn–xAg–0.7Cu solder joint

Unravelling the synergistic enhancement effect of Ag3Sn phase and graphene nanosheets addition on the thermal cycling reliability of Sn–xAg–0.7Cu solder joint

EBSD characterization of graphene nano sheet reinforced Sn–Ag solder alloy composites

This research explores the effects of incorporating Graphene Nano Sheets (GNS) on the microstructural characteristics and mechanical behavior of Sn–Ag solder alloys. The research was driven by the need for environmentally friendly, lead-free solder alloys with enhanced mechanical and thermal properties. The methodology involved incorporating graphene into the Sn–Ag alloy through stir casting, followed by a series of surface preparation techniques. The composite samples were then examined using EBSD to analyze crystallographic orientations and SEM/EDS for surface morphology and elemental composition. XRD provided insights into phase transformations and structural changes. Key findings reveal that the addition of GNS significantly refines the grain structure of the Sn–Ag alloy, leading to a bimodal grain size distribution. This refinement is attributed to the role of GNS as a nucleation site during solidification. Moreover, the study demonstrates a pronounced alteration in the texture of the material, with an increase in low-angle grain boundaries post-GNS addition. This texture change is indicative of enhanced mechanical properties. The results also show a shift in the orientation distribution function (ODF), suggesting a stronger crystallographic orientation due to GNS. These findings suggest that GNS incorporation could lead to improved mechanical and thermal properties in Sn–Ag solder, making them suitable for high-performance electronic applications. The study concludes that GNS not only serves as an effective reinforcement in Sn–Ag solder alloys but also significantly alters their microstructural and textural characteristics, contributing to the alloy's potential application in environmentally conscious electronic manufacturing.

An analysis of microstructural morphology, surface topography, surface integrity, recast layer, and machining performance of graphene nanosheets on Inconel 718 superalloy: Investigating the impact on EDM characteristics, surface characterizations, and optimization

Inconel 718 finds extensive applications in the aviation and aerospace industries, particularly in the manufacturing of jet engines and high-speed airframe components like fasteners, bolts, buckets, instrumentation parts, wheels, and spacers. It is also utilised in the production of cryogenic tankage and gas turbine blades. The present study focuses on investigating the machining performance of graphene nanosheets on Inconel 718. Various aspects of Inconel 718's machinability through electrical discharge machining (EDM) have been examined, including material removal rate (MRR), surface roughness, surface morphology, tool rear Rate (TWR), residual stresses on the machined surface, Vickers hardness, and recast layer thickness. The investigation reveals a significant impact of process parameters on these machining characteristics. The effects of graphene nanosheets have been observed using several analytical instruments such as field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), particle size analyzer, and X-ray diffraction (XRD). Furthermore, optimization of the response data with respect to input parameters has been performed in this study. TEM analysis is used to determine the size of individual debris particles in deionised water and mixed graphene nanosheet dielectric mediums. To verify that the debris particles are the same as the parent material, energy dispersive X-ray spectroscopy (EDX) is used. To determine the compounds and crystal structures present in the base metal and machined surfaces, XRD analysis is used. A high-resolution X-ray diffractometer (HRXRD) is used to measure the residual stresses on the machined surface. EDX composition testing is used to analyze surface modification. Due to the rapid heating and quenching that takes place in the dielectric medium, the machined surface becomes harder. Deposited materials, microholes, and surface textures can all be observed through FESEM microstructure observation. Comparing conventional EDM to nanosheets mixed dielectric, the thickness of the recast layer is reduced. To recapitulate, the study explores how various machining parameters and dielectric mediums affect EDM processes. It examines debris particle size, compound formation, residual stresses, surface modification, hardness, microstructure, and recast layer thickness. The addition of graphene nanosheets to the dielectric medium produces promising results, reducing the thickness of the recast layer and improving surface quality. The results offer suggestions for improving Inconel 718 material surface properties and EDM machining effectiveness.

Effect of graphene nano-additives on the fatigue limit of fiber-reinforced polymer hybrid composites—A micromechanical modeling procedure

In this article, the effect of graphene nanoadditives on the fatigue limit of unidirectional glass fiber-reinforced polymer (GFRP) composites has been investigated. A micromechanical model based on the crack growth has been used to analyze the fatigue limit response of unidirectional GFRP hybrid composite containing nanoadditives. The influence of different percentages of graphene nanosheets (GNS) and different types of nanofiller dispersion has been investigated by the micromechanical model. The fatigue limit of unidirectional GFRP hybrid composites has been plotted in terms of glass fiber volume fraction, interfacial friction shear stress, interfacial fracture energy and reference length. The fatigue limit of unidirectional composites can be improved by addition of GNS into the polymer matrix of such composite systems. The obtained results on the GNS dispersion type demonstrate that the uniform dispersion of GNS into the polymer matrix increases the fatigue limit of unidirectional GFRP hybrid composites. As the agglomeration density of GNS is low, the fatigue limit of GFRP hybrid composites will be improved more than when the density of agglomeration is high.

Mechanical Properties and Strain Hardening Behavior of Few‐Layered Graphene Nanosheets‐Reinforced Powder Metallurgy Nickel‐Based Superalloy Metal Matrix Composites

Herein, few‐layered graphene nanosheets (GNS) with approximately 3, 6, or 9 layers are used to reinforce high‐performance nickel‐based superalloy metal matrix composite. A powder metallurgy method comprising solution‐mixing, hot isostatic pressing, and thermal processing is used to prepare GNS‐FGH96 composites with different numbers of GNS layers as well as referential FGH96 matrix materials. Compared with those of unreinforced FGH96, the mechanical properties of the GNS‐FGH96 composites are enhanced, specifically, the ≈6 layers GNS‐FGH96 composite exhibits an ultimate tensile strength of 1660 MPa and a yield strength of 1229 MPa, which are 9.79% and 6.87% higher, respectively, than those without the addition of GNS. Furthermore, the ≈6 layers GNS‐FGH96 composite exhibits the highest elongation‐at‐fracture of 29.9%. The as‐prepared GNS‐FGH96 composites show a good balance of strength and ductility owing to the increased dislocation density between the FGH96 matrix and GNS reinforcement interface area, as well as the high structural integrity of the GNS. Thus, this study provides a novel approach for designing and creating high‐performance graphene‐reinforced FGH96 metal matrix composites that exhibit exceptional strength and toughness.

The cocontinuous morphology induced from the graphene nanosheets percolation network structures in the immiscible high density polyethylene/polyamide 6/graphene nanosheets composites

AbstractThe addition of graphene nanosheets (GNSs) into immiscible polymer composites to induce the cocontinuous morphologies shows potential application in reinforced nanocomposites and conductive polymer nanocomposites. In this work, immiscible high density polyethylene (HDPE)/polyamide 6 (PA6)/GNS composites were prepared via melt mixing. The electrical and rheological property of HDPE/PA6 composites filled with various GNS contents according to different viscosity ratios and mixing orders were investigated to reveal the double percolation effect via percolation scaling laws, and compared with those of HDPE/GNS and PA6/GNS composites. The morphology and GNS dispersion state of HDPE/PA6/GNS composites were examined via transmission electron microscopy and scanning electron microscope. Most of the GNS were selectively located in the PA6 phase of HDPE/PA6/GNS composites. The GNS‐related network and mixing order played important roles in the cocontinuous morphology formation and performance of HDPE/PA6/GNS conductive composites. Moreover, the addition of GNS also affected the crystallization kinetics and mechanical property of HDPE/PA6/GNS composites.

Preparation and properties of Ti(C,N)-based cermets with graphene nanosheet addition by spark plasma sintering

The application of Ti(C,N)-based cermets remains limited due to their low toughness. The fracture toughness of cermets can be significantly improved by using advanced sintering methods and appropriate additives. Here, cermets were prepared by spark plasma sintering (SPS) technology with graphene nanosheets (GNSs) and nano-scale tungsten carbide (WC) as additives. The effects of GNSs and sintering conditions on the microstructure, mechanical properties, and magnetic properties of Ti(C,N)-based cermets were studied. The results show that the sample with 0.6 wt% GNSs fabricated at 1450 °C, 8 min, and 35 MPa has a denser microstructure and better mechanical properties. The cermet has a Vickers hardness of HV 2415.40 and fracture toughness of 10.6 MPa·m1/2. Compared with the specimen without GNSs, the hardness and fracture toughness are significantly improved by 44.58% and 92.73%, respectively. A certain amount of GNSs can increase the movement of hard phases in the liquid phase, inhibiting their solubility and grain growth, and greatly improving the fracture toughness of cermets. The addition of nano-WC is conducive to promoting the formation of a (Ti,W) (C,N) rim phase and improving properties of cermets. SPS can activate particle surfaces and promote the densification of cermets.

Effect of Graphene Nanosheets on the Microstructure and Mechanical Properties of Sn-20Bi Solder.

The application of Sn-Bi series solder is limited due to the brittleness of Bi phase. Sn-20Bi solder with less Bi element content has great research prospects, but it needs modification to make it a substitute for traditional Sn-Pb solder. In this article, we mixed graphene nanosheets with nanometer Sn powder by means of ultrasonic oscillation, and Sn-20Bi-qGNS (q = 0.01, 0.02, 0.04, 0.06, and 0.1 wt.%) solder alloys were prepared by the melt-casting method. The effects of graphene nanosheets (GNSs) on the microstructure, physical properties, mechanical properties, and corrosion resistance of solder alloys were investigated. Scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were used to determine the microstructural morphology and composition. The results showed that the melting point, density, and wettability of the solder decreased slightly with the addition of GNSs. The addition of GNSs as a second phase refined the solder structure and improved the tensile strength of the molten Sn-20Bi composite solder to 99.6 MPa, while elongation decreased with the addition of GNSs. Furthermore, GNSs prevented the MC Sn-20Bi-qGNSs/Cu intermetallic compound layers' growth by interfering with atomic diffusion and grain boundary movement. In addition, the addition of 0.02 wt.% GNSs enhanced the shear strength of MC Sn-20Bi solder joints to 46.3 MPa. The electrochemical experimental results show that the surface corrosion products of MC Sn-20Bi-qGNSs under 3.5% NaCl solution were Sn3O(OH)2Cl2, with MC Sn-20Bi-0.01GNSs exhibiting the best corrosion resistance.

Structural and physicomechanical properties of rice husk Ash-based geopolymer mortar with the addition of graphene nanosheets

Structural and physicomechanical properties of rice husk Ash-based geopolymer mortar with the addition of graphene nanosheets

Enhancement of Physical Properties and Corrosion Resistance of Al-Cu-Al2O3/Graphene Nanocomposites by Powder Metallurgy Technique.

In this study, we enhanced the adhesion of graphene nanosheets to achieve homogeneous dispersion, consequently improving the electrical and thermal conductivity, coefficient of thermal expansion, and corrosion resistance with an aluminum matrix containing up to 1.5 wt. % graphene. First, 2.5 wt. % Al2O3 and varying ratios of graphene up to 1.5 wt. % were coated with 5 wt. % silver nanoparticles to metalize their surfaces. Predetermined portions of coated alumina and graphene were mixed with Al/10 wt. % Cu powder for 45 h. Mixed samples were compacted under 600 MPa and sintered at 565 °C in a vacuum furnace for 60 min with a low heating rate of 2 °C/min. The strengthening effect of the added materials on the density, microstructure, electrical and thermal conductivities, thermal expansion, and corrosion behavior of aluminum were investigated. Excellent adhesion and homogeneous dispersion of the investigated reinforcements were achieved. Three phenomena were observed: (1) an improvement in the densification, electrical and thermal conductivity, thermal expansion, and corrosion rate by adding 10 wt. % Cu to the aluminum matrix; (2) deterioration of the properties of Al/10 wt. % Cu with the addition of 2.5 wt. % alumina nanoparticles; and (3) improved properties with the addition of graphene nanosheets up to 1 wt. % and a decrease in property values beyond 1.5 wt. % graphene content due to the formation of agglomerations and pores in the metal matrix.

Graphene modified phosphate-based metal/ceramic composite coating for corrosion protection in the high-temperature marine environment

Graphene-modified phosphate-based metal/ceramic composite coatings were prepared for corrosion protection in the high-temperature marine environment. The morphology and structure of the coating were observed by SEM, and the high-temperature anticorrosion performance of the coating was analyzed by electrochemical measurement and salt spray-high temperature cycle test. The results showed that the addition of 0.1 wt% graphene could bridge the aluminum particles inside the composite coating and extend the sacrificial anode protection time of the coating in the 3.5 wt% NaCl solution from less than 4 days to more than 8 days, thus avoiding the local failure of the coating and improving the anticorrosion performance. Besides, the addition of graphene nanosheets at low content also enhanced the physical barrier effect of the coating and prolonged the penetration path of the corrosive medium without destroying the structure of the composite coating.

Preparation and Properties of Ti(C,N)-Based Cermets with Graphene Nanosheets Addition by Spark Plasma Sintering

Preparation and Properties of Ti(C,N)-Based Cermets with Graphene Nanosheets Addition by Spark Plasma Sintering

Experimental and modeling analysis of p-type Bi0.4Sb1.6Te3 and graphene nanocomposites

The state-of-the-art Bismuth-Telluride (Bi2Te3) based systems are promising thermoelectric materials for efficient thermoelectric applications. In this study, the effect of graphene nanosheets (GNS) integrity on thermoelectric properties of a p-type Bi0.4Sb1.6Te3 alloy has been studied using high-energy ball milling and SPS sintering techniques. The synthesized pristine Bi0.4Sb1.6Te3 and 0.05wt% GNS/Bi0.4Sb1.6Te3 nanocomposites at different addition times of GNS have exhibited a single-phase and artifact-free bulk nanocrystalline Bi0.4Sb1.6Te3 with nanocrystals size of 17 nm. The TEM analysis confirmed the mechanical exfoliation of graphene filler in 5m nanocomposite into a single-layered nanostructure with an interplanar spacing of 0.343 nm. The prominent Raman features of the monolayered graphene sheet have appeared in the synthesized 5m-GNS/Bi0.4Sb1.6Te3 nanocomposite. This highlighted the crucial rule of graphene addition time on its structure and morphology of the synthesized nanocomposites. The ZT profile of 5m nanocomposite reached 0.801 at 348 K till 398 K. This resulted in 65% of improvements to the pristine Bi0.4Sb1.6Te3 pellet at 323 K. The obtained results were used to simulate a thermoelectric (TE) device module using ANSYS Workbench. The GNS nanocomposites have shown an ultrahigh output power of 95.57 W compared to 89.96 W for the pristine module at ΔT of 150 °C. The GNS addition has increased the output power of pristine Bi0.4Sb1.6Te3 by 7%, leading to comparable TE performance to other simulated Bi2Te3 systems.

Tribological and rheological evaluation of a graphene nanosheets-based lubricant for metal-on-metal and wet clutch interfaces

The tribological and rheological behavior of mineral oil (MO) additivated with graphene nano-sheets (GNS) as lubricant in metal-on-metal interfaces and actual wet clutch materials was analyzed in this work with a focus on its potential use in automatic transmission (AT) systems. Lubricants prepared with different GNS concentrations (0.1, 0.5, 1.0 w/v%) in MO were evaluated in shear flow (viscosity changes) and by ball-on-disc measurements. Besides, thermogravimetric analysis and wet clutch friction tests at 26 and 100 °C were performed. Overall, the GNS addition to MO made the lubricants non-Newtonian shear-thinning and increased their viscosity at high shear rates, reduced the wear rate for the metallic interfaces tested, and enhanced the thermal stability and oil anti-shudder property of the wet clutch.

Fabrication of multilayered carbon fibrous membranes for high-efficiency electromagnetic absorption

Carbon fibrous (CF) membranes were fabricated by electrospinning, thermal stabilization, and the carbonization process. The in-depth analyses of the CF membranes’ composition, structure, and microwave absorption (MA) property demonstrate that the MA performance of the membranes is strongly correlated with the C/O ratio and CF framework's microstructure. A maximum absorption value of −23.4 dB is achieved at 800 °C, and this was synergistically enhanced to −42.5 dB with the addition of graphene nanosheets (GNSs). The special multilayered membranes containing dielectric loss CNSs and CFs making the balance between excellent impedance matching and the high loss characteristic could deliver an excellent MA property. With the facile and controllable synthesis of the GNS/CF membranes, a new approach to efficiently optimize and regulate its MA behavior is now possible.

Graphene nanosheet as a new particle dispersant for the jet-electrodeposition of high-performance Ni-P-WC composite coatings

Graphene nanosheet (GNS) was considered as a new dispersant to inhibit the agglomeration of nanoparticles in plating solution. The addition of graphene nanosheet in jet-electrodeposition could effectively increase the number of nanoparticles deposited in the coating, and give full play to the role of nanoparticles in improving the performance of the coating. Ni-P-WC-GNSs composite coatings were prepared on the #45 steel by jet-electrodeposition to explore the effect of different concentration of GNSs on the properties of nickel-based coatings. Scanning electron microscopy was used to explore the micromorphology, hardness measurement instrument was used to measure microhardness , comprehensive property tester and CS350 electrochemical workstation were used to explore the wear resistance and corrosion resistance . Results indicated that the addition of GNSs could reduce and inhibit the agglomeration of nanoparticles; enhance the surface quality and strengthen the hardness, wear resistance and corrosion resistance of the composite coating. With the increase of GNS concentration, the improvement effect initially showed an increasing trend and then a decreasing trend. When the GNSs concentration were 0.4 g/L, the average hardness reached the maximum value of 709.2 HV 0.1 ; the scratch area reached the minimum value of 1381.9 μm 2 ; the corrosion current reached the minimum value of 1.026 × 10 −6 A·cm −2 , and the corrosion potential reached the maximum value of −0.249 V. Composite coating had the best property at that time, and GNSs inhibited the agglomeration of nanoparticles and significantly improved the coating performance. • Use jet electrodeposition to prepare composite coatings with excellent performance • Graphene nanosheets (GNSs) were added to inhibit the agglomeration of nanoparticles. • Explore the effect of concentrations of GNSs on the performance of coatings

Fabrication and characterization of polyaniline functionalized graphene nanosheets (GNSs)/polydimethylsiloxane (PDMS) nanocomposite films

In this study, graphene nanosheets (GNSs)/poly(dimethylsiloxane) (PDMS) nanocomposites and the novel polyaniline (PANI)-functionalized graphene nanosheets (GNSs)/poly(dimethylsiloxane) (PDMS) nanocomposites were fabricated successfully. GNSs and PANI-functionalized GNSs were dispersed in PDMS matrix at different nanofiller concentration and nanocomposites were prepared via solution casting method. PANI functionalization were performed by in-situ polymerization of aniline in the presence of GNSs and was used in order to be dispersed homogenously and efficiently in the PDMS matrix. Besides graphene layers were also isolated to hinder aggregation in the polymeric matrix. The effect of PANI functionalization of GNSs and filler concentration on dielectric, electrical and mechanical properties of nanocomposite films were investigated. According to dielectric measurements, the dielectric constant of polymer nanocomposites highly dependant on frequency, so dielectric constant was characterized in a wide frequency range (1 Hz–10 MHz) at room temperature, in this study. The dielectric constant of PDMS nanocomposites containing 1.50% GNSs and 1.50% PANI-GNSs increased by 111 times and 24 times, at 1 Hz, compared to pure PDMS, respectively. Besides, electrical conductivity increased 6868 and 1474 times with the addition of GNSs and PANI-GNSs, respectively. Optimized GNSs/PDMS and PANI-functionalized GNSs/PDMS nanocomposites can be candidate for soft actuators to be used in artificial muscle applications, in the future.

Experimental study on mechanical properties of polypropylene nanocomposites reinforced with a hybrid graphene/PP-g-MA/kenaf fiber by response surface methodology

In this study, the mechanical properties of polypropylene (PP)-based nanocomposites reinforced with graphene nanosheets, kenaf fiber, and polypropylene-grafted maleic anhydride (PP-g-MA) were investigated. Response surface methodology (RSM) based on Box–Behnken design (BBD) was used as the experimental design. The blends fabricated in three levels of parameters include 0, 0.75, and 1.5 wt% graphene nanosheets, 0, 7.5, and 15 wt% kenaf fiber, and 0, 3, and 6 wt% PP-g-MA, prepared by an internal mixer and a hot press machine. The fiber length was 5 mm and was being constant for all samples. Tensile, flexural, and impact tests were conducted to determine the blend properties. The purpose of this research is to achieve the highest mechanical properties of the considered nanocomposite blend. The addition of graphene nanosheets to 1 wt% increased the tensile, flexural, and impact strengths by 16%, 24%, and 19%, respectively, and an addition up to 1.5 wt% reduced them. With further addition of graphene nanosheets until 1.5 wt%, the elastic modulus was increased by 70%. Adding the kenaf fiber up to 15 wt% increased the elastic modulus, tensile, flexural, and impact strength by 24%, 84%, 18%, and 11%, respectively. The addition of PP-g-MA has increased the adhesion, dispersion and compatibility of graphene nanosheets and kenaf fibers with matrix. With 6 wt% PP-g-MA, the tensile strength and elastic modulus were increased by 18% and 75%, respectively. The addition of PP-g-MA to 5 wt% increased the flexural and impact strengths by 10% and 5%, respectively. From the entire experimental data, the optimum values for elastic modulus, as well as, tensile, flexural, and impact strengths in the blends were obtained to be 4 GPa, 33.7896 MPa, 57.6306 MPa, and 100.1421 J/m, respectively. Finally, samples were studied by FE-SEM to check the dispersion of graphene nanosheets, PP-g-MA and kenaf fibers in the polymeric matrix.

Experimental analysis of mechanical properties of graphene/kenaf/basalt reinforced hybrid nanocomposites using response surface methodology

In this study, the flexural strength and elastic modulus of polypropylene-based nanocomposites reinforced with graphene nanosheets, basalt, and kenaf fiber were investigated. Response surface methodology based on Box–Behnken design was used as the experimental design. The blends fabricated in three levels of parameters include 0, 0.75, and 1.5 wt% graphene nanosheets, 0, 7.5, and 15 wt% basalt fibers, and 0, 7.5, and 15 wt% kenaf, prepared by an internal mixer and a hot press machine. The fiber length was 5 mm and was being constant for all samples. Flexural and tensile tests were conducted to determine the blend properties. The addition of graphene nanosheets to 0.75 wt% increased the flexural strength by 12% and a graphene addition up to 1.5 wt% reduced flexural strength by 6%. The addition of graphene nanosheets to 1.5 wt% increased the elastic modulus by 37%. The addition of basalt fiber up to 15 wt% increased the flexural strength and elastic modulus by 13% and 61%, respectively. The addition of kenaf fiber up to 15 wt% increased the flexural strength by 18% and the elastic modulus by 46%. Finally, samples were studied by field emission scanning electron microscopy to check the dispersion of graphene nanosheets, basalt, and kenaf fibers in the polymeric matrix.

Compressive Strength of Coal Fly-ash Based Geopolymer with Integration of Graphene Nanosheets (GNs)

The compressive strength of coal fly ash-based geopolymers has been improved by integrating the graphene nanosheets (GNs) as additive. Proximate analysis and crystal structure were also investigated using atomic absorption spectroscopy (AAS) and X-ray diffractometer. The geopolymer composites were created by mixing the solid fly ash and sand (weight ratio of 1:3) with 10 M NaOH and sodium silicate (Na2SiO3) solutions (weight ratio of 1: 2.5), where the liquid to solid weight ratio reached an economical composition of 1: 4. Low-cost GNs with various concentrations of 5 – 20 mg/ml was then added to the mixtures. The prepared mixtures were poured into mortar molds and allowed to stand for few hours at room temperature before heat treatment (curing) in the oven at various temperatures of 40°C, 60°C, and 80°C for 24 hours. Investigation results showed that the average compressive strength of geopolymer increased about 113.8 % or more than double compared to geopolymer without the addition of GNs. The highest compressive strength (29.5 MPa) was shown by a sample with GNs of 20 mg/mL and a curing temperature of 8°C. Meanwhile, geopolymer without GNs showed the lowest compressive strength in all curing temperatures. Proximate analysis showed that fly ash used in this work was the high calcium of type-C fly ash with the CaO content of 11.18%. XRD analysis results indicated that the GNs had integrated well in the geopolymer matrix. The presence of graphene-like structure was also detected, but it was not agglomerated with GNs. Good compressive strength and inexpensive production processes make this geopolymer very prospective for further development.