Incorporation Of SiC Nanoparticles Research Articles

Electrodeposited FeCoNiWMo high entropy alloy/SiC nanocomposite coatings: Microstructure, mechanical properties and corrosion resistance

In this study, FeCoNiWMo/SiC high entropy alloy nanocomposite coatings were deposited at various contents of SiC nanoparticles in the bath. The effect of the addition of SiC nanoparticles on some properties of the electrodeposited FeCoNiWMo high entropy alloy matrix was evaluated. The morphological, elemental, and phase structure were analyzed by SEM, EDX, and XRD. For mechanical measurements, Vickers microhardness and pin-on-disk wear test were performed. A potentiostat-galvanostat device was used to determine corrosion resistance. The results show that the incorporation of SiC nanoparticles changes both the microstructure and morphology of the matrix from amorphous with FCC solid solution and nodular morphology to FCC solid solution with granular structure. By increasing the SiC content, the coatings showed improved microhardness, wear resistance, and corrosion performance. At optimum concentration (20 g/L), the nanocomposite exhibited the highest microhardness, wear resistance, and corrosion resistance.

Improvement of Structures and Properties of Al2O3 Coating Prepared by Cathode Plasma Electrolytic Deposition by Incorporating SiC Nanoparticles

A serious issue in the preparation of Al2O3 coatings by cathode plasma electrolytic deposition (CPED) is that the coatings have a porous structure, which is detrimental to their protective performance. Therefore, to address this problem, SiC nanoparticles are incorporated into the Al2O3 coating in this study. A series of Al2O3–SiC composite coatings are efficaciously prepared on the surface of 316L stainless steel by CPED. The microstructures, compositions and phase components of the composite coatings are characterized; the electrochemical corrosion resistance and tribological behavior are evaluated; and the mechanism of SiC nanoparticles in the coating formation process is discussed in detail. The results indicate that the Al2O3 coating prepared by CPED consists of α-Al2O3 and γ-Al2O3, and the former is the main crystalline phase. With the incorporation of SiC nanoparticles in the coating, the content of α-Al2O3 gradually decreases, almost disappearing, accompanied by an increase in γ-Al2O3 as the main crystalline phase. The incorporation of SiC nanoparticles significantly reduces the surface irregularity and roughness of Al2O3 coatings and remarkably improves the corrosion resistance and wear resistance of the Al2O3 coatings. The improvement in corrosion resistance and anti-wear properties can be explained by the fact that the SiC nanoparticles effectively weaken electrical breakdown and increase the compactness of the coatings.

Failure analysis of scarf adhesive joints modified with SiC-nanoparticles under fatigue loading at room temperature

Adhesive joints were fabricated by joining two woven carbon fiber composite adherends with scarf angle of 5° using Epocast adhesive system of 50-A1/946 modified with optimum weight percent of 1.5 wt% SiC-nanoparticles. The scarf adhesive joints (SAJs) were characterized through static tensile as well as tension-tension fatigue loading. The stress-number of cycles to failure curves are useful in determining the fatigue life, but they do not give any indication about the fatigue damage development during the joint's lifetime. In consideration of early detecting damage development in the SAJs, many dynamic parameters were estimated from the analysis of the stress-local strain cycles, with the aim to obtain more accurate predictions. These parameters include loss and storage moduli, potential and dissipated energies, and damping factor. It has been found that the tensile strength and fatigue limit of the SiC-SAJ were increased by 9.6% and 55% respectively with decreasing the bondline thickness from 0.25 mm to 0.17 mm. Incorporation of SiC-nanoparticles into the adhesive layer improves the tensile strength and the fatigue limit of the SAJs with bondline thickness of 0.17 mm by 26.1% and 22% respectively compared to the unmodified joint. At higher stress levels, the storage modulus and potential energy can be modeled for early prediction of the joint life and thereby, help in preventing their catastrophic failure. Zhang model showed good agreement with the measured potential energy compared to the storage modulus.

Effect of SiC Nanoparticles on AZ31 Magnesium Alloy.

Magnesium alloys are attractive for the production of lightweight parts in modern automobile and aerospace industries due to their advanced properties. Their mechanical properties are usually enhanced by the incorporation with reinforcement particles. In the current study, reinforced AZ31 magnesium alloy was fabricated through the addition of bulk Al and the incorporation of SiC nanoparticles using a stir casting process to obtain AZ31-SiC nanocomposites. Scanning electron microscope (SEM) investigations revealed the formation of Mg17Al12 lamellar intermetallic structures and SiC clusters in the nanocomposites. Energy dispersive spectroscopy (EDS) detected the uniform distribution of SiC nanoparticles in the AZ31-SiC nanocomposites. Enhancements in hardness and yield strength (YS) were detected in the fabricated nanocomposites. This behavior was referred to a joint strengthening mechanisms which showed matrix-reinforcement coefficient of thermal expansion (CTE) and elastic modulus mismatches, Orowan strengthening, and load transfer mechanism. The mechanical properties and wear resistance were gradually increased with an increase in SiC content in the nanocomposite. The maximum values were obtained from nanocomposites containing 1 wt% of SiC (AZ31-1SiC). AZ31-1SiC nanocomposite YS and hardness were improved by 27% and 30%, respectively, compared to AZ31 alloy. This nanocomposite also exhibited the highest wear resistance; its wear mass loss and depth of the worn surface decreased by 26% and 15%, respectively, compared to AZ31 alloy.

Effect of SiC addition in electrolyte on the microstructure and tribological properties of micro-arc oxidation coatings on Al-Mg-Sc alloy

sHard and wear-resistant ceramic coatings with SiC nanoparticles were in situ fabricated on Al-Mg-Sc alloy using micro-arc oxidation (MAO) method in alkaline silicate electrolyte. The microstructure, roughness, and composition of the MAO coatings were characterized by scanning electron microscopy (SEM), x-ray diffraction (XRD) and laser scanning confocal microscopy (LSCM), respectively. The microhardness of the MAO coatings was obtained microhardness tester. The wear resistance of the MAO coatings was evaluated by ball-on-disc reciprocating tribo-tester. The results showed that the phase composition of the obtained coatings with the typical pancake-like stacking structures was mainly composed of α-Al2O3 and γ-Al2O3. the porosity and roughness gradually decreased with the increment of SiC nanoparticles concentration. Al content gradually decreased from the matrix to the outside, while the Si content gradually increased. The incorporation of SiC nanoparticles further increased the microhardness of the MAO coating. Especially in alkaline silicate electrolyte with 1.5g l−1 SiC nanoparticles, the microhardness could reach 1270 HV0.5. The friction coefficient of the MAO coatings prepared in electrolyte solution with SiC addition varied from 0.4 to 0.55, and the ceramic coating with 1.5g l−1 SiC nanoparticles exhibited the best wear resistance. The wear mechanism was attributed to be the combination of abrasive wear, adhesive wear and oxidation wear.

SiC nanoparticles incorporation in electroless NiP-Graphene oxide nanocomposite coatings

The presence of SiC nanoparticles within the Graphene oxide (GO) incorporated electroless deposited NiP layers (NiP-GO) on carbon steel substrate was studied in this work. The effect of co-deposition of GO nanoplatelets and/or SiC nanoparticles on the morphology and structure of the heat-treated NiP coatings were investigated by scanning electron microscope and X-ray diffraction, respectively. The results revealed that the heat-treated NiP and NiP–SiC coatings consisted of Ni and Ni3P phases, whereas the NiP-GO also contains the intermediated Ni2P and Ni12P5 metastable phases due to the incomplete precipitation of Ni3P. Such metastable phases are significantly decreased by the incorporation of SiC nanoparticles in NiP-GO coatings. The mechanical properties of the coatings were characterized by microhardness measurement and “pin on disk” wear test. The corrosion tests were conducted in aqueous 3.5 %wt NaCl using electrochemical measurement for Ni–P, NiP-GO, NiP–SiC, and NiP-GO-xSiC coatings. By co-deposition of SiC nanoparticles, the hardness of NiP-GO is significantly increased and the wear loss is reduced, especially at a high sliding distance during the wear test. The corrosion behavior of the NiP-GO coatings containing different amounts of SiC nanoparticles has been investigated.

Electrochemical tailoring of Pb-free Sn coatings modified with SiC nanoparticles by surfactant-assisted reverse pulse plating

In this study, reverse pulse plating technique was used to study the effect of various surfactants (anionic, non-ionic, and cationic) in electrolytes and incorporation of SiC nanoparticles (NPs) in the Sn matrix. The microstructural and electrochemical observations indicate that the incorporation of SiC in Sn coating depends upon the type of surfactants. The composite stress moves from compressive to tensile with SiC content. The maximum grain refinement of Sn-SiC coatings was found in the presence of a cationic surfactant in the electrolyte while a minimum value of resistivity was displayed by coatings prepared in anionic surfactant. The corrosion behavior of Sn-SiC coatings showed superior corrosion protection ability of non-ionic surfactants amongst other surfactants used here.

Thermoelectric and Mechanical Properties of Environmentally Friendly Mg2Si0.3Sn0.67Bi0.03/SiC Composites.

In this work, polycrystalline n-type Mg2Si0.30Sn0.67Bi0.03 dispersed with x wt % β-SiC nanoparticles (x = 0, 0.5, 1.0, 1.5, and 3.0) thermoelectric materials were fabricated by a solid-state reaction in a low-cost container, consolidated by hot-pressing. We obtained figureofmerit valueszT above 1.4 at 773 K along with enhanced mechanical properties by adding β-SiC into an Mg2Si0.30Sn0.67Bi0.03 matrix. Incorporation of SiC nanoparticles has thusly simultaneously increased toughness and, depending on the SiC content, thermoelectric performance. The peak figure of merit was improved from zT = 1.33 for Mg2Si0.30Sn0.67Bi0.03 to 1.45 for Mg2Si0.30Sn0.67Bi0.03 with 3 wt % at 773 K.

Texture variations and mechanical properties of aluminum during severe plastic deformation and friction stir processing with SiC nanoparticles

Annealed 1050-aluminum sheets were severely deformed at the strain magnitude of 2.32 through constrained groove pressing (CGP) process. Texture variations and mechanical properties were investigated during CGP and subsequent friction stir processing (FSP) with different volume fractions of SiC nanoparticles. The results revealed that the predominant texture component in the annealed aluminum was {001}〈100〉 cube texture. After CGP, deformed and shear texture components developed while the cube texture was partially remained. In the specimen undergone FSP without nanoparticles, {001}〈110〉 rotated cube and nearly {001}〈110〉 shear texture component C were mainly pronounced, which was indicative of shear deformation of material in the stir zone. Orientation distribution function analysis from the stir zone demonstrated variations in the texture development with the incorporation of SiC nanoparticles. An increase in the fraction of nanoparticles changed the grain orientation in such a way that the {001}〈110〉 shear texture component C gradually developed from the rotated cube texture. However, the overall texture intensity became weaker by increasing the fraction of SiC nanoparticles due to the activation of particle stimulated nucleation mechanism forming randomly oriented grains. The incorporation of SiC nanoparticles in the stir zone also enhanced the yield strength, Young's modulus, and hardness of the stir zone without considerable reduction in the elongation. In such situation, Orowan strengthening was suggested as a dominant mechanism involved.

Influence of SiC Nano Particles on Microhardness and Corrosion Resistance of Electroless Ni–P Coatings

Silicon carbide nanoparticles were co-deposited in Ni–P matrix to form Ni–P–SiC composite coating on the mild steel substrate by using electroless coating technique. In the present study, the effect of SiC nanoparticles concentration and heat treatment temperature on microhardness and corrosion resistance of the Ni–P–SiC coating was investigated. The microhardness and corrosion resistance of the coating was further analyzed through the experiments. X-ray diffraction and scanning electron microscope attached with energy dispersive spectroscopy were used to analyze phase structure, morphology, and elemental composition of the coating. Results confirm that incorporation of SiC nanoparticles into the coating greatly influences the microhardness and corrosion resistance of the coating. The phase change from amorphous Ni to crystalline nickel and nickel phosphide at 400 °C further improves the microhardness and corrosion resistance of the composite coating.

Optimization of mechanical and microstructural properties of friction stir spot welded AA 6061-T6 reinforced with SiC nanoparticles

The aim of this study is to improve weld characteristics employing a new proposed method in adding SiC reinforcement nanoparticles to friction stir spot welds (FSSW). 6061-T6 aluminum alloy plates 3 mm in thickness and SiC nanoparticles 45 to 65 nm in diameter were used in FSSW. Design of experiments, S/N ratio analysis and optimization of joint ultimate strength were conducted using Taguchi method. In this way, the amount of nanopowder, tool rotational speed and dwell time were considered as input parameters to optimize joint ultimate strength. A confirmation test was also conducted which validated optimal measure predicted by Taguchi. The fracture mode of each examined specimen was specified by an investigation of their force-displacement graphs and failed nugget surfaces. The specimen microstructures were examined next and grain size and nanoparticles distribution in weld region were evaluated. Achieved results justified the effect of design parameters on ultimate strength and microhardness of the joint. Energy dispersive x-ray spectroscopy (EDS) indicated that nanoparticles assembled in grain boundaries during dynamic recrystallization and prevented the growth of grain size. Incorporation of SiC nanoparticles in FSSW increased joint ultimate strength and average hardness in stir zone (SZ) up to 28% and 24%, respectively.

Dynamic restoration and crystallographic texture of a friction-stir processed Al–Mg–SiC surface nanocomposite

ABSTRACTIn this study, SiC nanoparticles (∼50 nm, 3 vol%) are homogenously incorporated within an Al–Mg alloy metal matrix during multi-step friction-stir processing (FSP) to fabricate an Al-matrix surface nanocomposite. A fundamental understanding is developed, correlating microstructural features and crystallographic textural components in the context of the material flow pattern and operative dynamic restoration phenomena using electron backscattering diffraction and high resolution-transmission electron microscopy analysis. The annealed base metal does not contain any preferred orientation and its texture is completely random. Incorporation of SiC nanoparticles via FSP results in significant grain structural refinement down to the size of ∼1.4 µm and changing the textural component towards the Goss/Cubic and P1/P2 dominant fibre components in the centre of stirred zone.

Mechanical properties and morphology of aluminium metal matrix nanocomposites-stir cast products

In the present work, A356/SiC nanocomposites have been fabricated through stir casting process. Mechanical properties, morphology and effect of SiC nanoparticles on A356/SiC nanocomposites have been studied. SiC nanoparticles were varied from 1 to 5% by weight in a step of 1%. Aluminium fine powder and SiC nanoparticles were mechanically milled before mixing SiC nanoparticles into the melts. Hardness, tensile and compressive test results were enhanced with the addition of nanoparticles. Toughness, elongation and forgeability decreased with the incorporation of SiC nanoparticles. Hardness increased by 125%. The improvement of 41% in YTS and 45% in UTS and 603 MPa in compressive strength in case of A356/5%SiC nanocomposites were observed. To identify the involvement and presence of the SiC nanoparticles into the matrix alloy, fractured surfaces of the fabricated nanocomposites were examined using SEM with EDX spectrum. SEM micrographs disclosed the nature of the fractured mechanism. Proper distribution of SiC nanoparticles were attributed by SEM micrographs. The main constituents present in the nanocomposites were verified by EDX spectrum.

Influence of Composite Nano-Coating of Ni-Co-SiC Obtained by Electrodeposition on the Corrosion Resistance of API 5L X80 Steel

Corrosion problems are frequent and occur in various sectors of industries, resulting consequences of economic order and serious accidents involving human lives and contaminating the environment. The electrodeposition is one of the most popular methods for preventing corrosion, where the Ni-Co metal matrix has been widely applied. The incorporation of SiC nano-particles in electrochemical baths produces nanocomposite coatings to synergistic properties with potential application in anti-corrosion protection. The objective of this work was to develop the Ni-Co-SiC nano-coating electrodeposited on API 5L X80 steel and evaluate the corrosion resistance. Open circuit potential (OCP), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PP) measurements were performed in 3.5% NaCl solution. To correlate with corrosion behavior, scanning electron microscopy (SEM), energy-dispersive X-ray spectrum (EDXS) and Vickers micro-hardness tests on the nano-coating were performed.

Effect of microtexturing on tribological performance of Ni/Ni–SiC composite coatings

Laser surface texturing is one of the promising surface modification techniques to reduce wear and friction properties of materials. In this study, we report the comparative effect of laser surface texturing on commercial nickel, electrodeposited nickel and Ni–SiC composite coatings. Hemispherical dimples, with 80–200 μm dimple spacing, were created and examined on the surfaces of the materials studied. The results revealed that microsurface texturing with 150 μm dimple spacing considerably improved the coefficient of friction. Electrodeposited nickel has shown improved coefficient of friction under identical texturing and tribological conditions when compared to commercial nickel. Furthermore, incorporation of SiC nanoparticles in nickel, by codeposition processes, resulted in the increase in microhardness of the coating, which in turn prevented the dimples from being deformed after wear testing. Dimple spacing accuracy and incorporated second phase ceramic particles both contributed significantly to reduction in coefficient of friction of electrodeposited Ni–SiC composite coatings.

An improvement of the wear and corrosion resistances of AZ31 magnesium alloy by plasma electrolytic oxidation in a silicate–hexametaphosphate electrolyte with the suspension of SiC nanoparticles

Plasma electrolytic oxidation (PEO) of AZ31 magnesium alloy under pulsed bipolar constant current regimes has been carried out in a silicate–hexametaphosphate electrolyte without and with the suspension of SiC nanoparticles. The coatings were characterized by eddy current method, X-ray diffraction (XRD), scanning electron microscopy (SEM), dry sliding wear and electrochemical tests. Higher growth rates were found for the coatings formed with the presence of nanoparticles. The incorporation of SiC nanoparticles into the coatings has been verified by XRD and SEM, and the incorporated particles were found to distribute relatively uniformly along the coating depth. “Weak sites” existed in the SiC free coatings, which significantly lowered the wear performance of the coatings. In contrast, “weak sites” are not found in the coatings with the incorporation of SiC nanoparticles, resulting in an excellent wear performance of the coatings. The applied current densities of the PEO processes also affect the performance of the coatings, with higher wear rates for the coating prepared under higher current densities. All the coatings show improved corrosion resistances.

Direct current electrodeposition of Zn and Zn–SiC nanocomposite coatings

Pure Zn and Zn matrix composite coatings containing nano-sized SiC particles with an average size of 50 nm were prepared from the zinc sulphate bath. The effect of the particle concentration and current density on the amount of particles embedded was examined. Electron microscopic studies revealed that the coating morphology was modified by the presence of SiC nanoparticles. Corrosion resistance properties of the coatings were studied using a potentiodynamic polarisation technique in 1M NaCl solution. It was established that agglomeration of nanoparticles worsens corrosion resistance properties of Zn–SiC coatings. However, the presence of well dispersed nanoparticles significantly improves the corrosion resistance of the zinc. Incorporation of SiC nanoparticles also improves the microhardness of the zinc matrix.

A comparative study of the effects of saccharin and β-SiC nano-particles on the properties of Ni and Ni–Co alloy coatings

The effects of saccharin and SiC nano-particles on the properties of Ni and Ni–Co based coatings electrodeposited in modified Watt's baths by sediment co-deposition (SCD) technique were studied. Surface morphologies of Ni and Ni–Co coatings were changed by using saccharin and SiC nano-particles. X-ray diffraction (XRD) results revealed that peak positions and the phase structure of the studied coatings did not change appreciably while the crystallite size and preferred orientation were significantly varied by using SiC nano-particles and particularly saccharin. Although the incorporation of SiC nano-particles had a slight influence on the microhardness of Ni based coatings, using saccharin enhanced their microhardness. However, there was no noticeable difference between the microhardness of Ni–45Co and Ni–45Co/saccharin coatings (containing 45wt.% Co) while the microhardness of Ni–55Co/SiC nanocomposite coatings (containing 55wt.% Co) was higher than Ni–45Co and Ni–45Co/saccharin coatings. The potentiodynamic polarization measurements indicated that the corrosion resistance of Ni/saccharin and Ni–45Co/saccharin coatings was better than pure Ni and Ni–45Co coatings. Additionally, the corrosion properties of Ni/SiC and Ni–55Co/SiC nanocomposite coatings were markedly higher than other coatings. Ni–55Co/SiC nanocomposite coatings showed the highest microhardness and corrosion resistance compared to all studied coatings. The unique properties of Ni–55Co/SiC nanocomposite coatings were linked to their alloy matrix and the amount of SiC nano-particles (8.1vol.%).

A study of electrodepositing Sn–SiC composite coatings with good welding performances

Sn–SiC composite coatings with a good welding performance were electrodeposited in a bath containing 55 g L−1 Sn(CH3SO3)2, 160 g L−1 methyl sulfonic acid (MSA), 10 mg L−1 OP-21, 30 g L−1 SiC nano-particles and 50 mg L−1 sodium dodecyl sulfate (SDS), at an inclination angle of the plating tank θ of 45°, a temperature of 20 °C and a cathode–current density of 3 A dm−2 for 15 minutes. The incorporation of SiC nano-particles in the Sn deposits refines the crystalline grains. The solder spreading performance and Sn whiskers of the Sn–SiC coatings composited with 1.0–2.3 wt% SiC are better and smaller than that of the pure Sn coating, respectively. Only when the intercalation of SiC nano-particles into the Sn grain boundary is firm and homogeneous could coatings with a good welding performance be obtained.

Erosion–corrosion resistance of Ni composite coatings with embedded SiC nanoparticles

This study assessed the erosion–corrosion behavior of pure Ni and Ni–SiC composite coatings evaluated in a corrosive environment using in situ potentiondynamic polarization and electrochemical impedance. Coatings were obtained from a Watts classical solution in which SiC nanoparticles were added. Coatings were galvanostatically deposited on carbon steel on a rotating disk electrode. The hydrodynamic conditions of the bath and the content of SiC in the electrolyte were varied. The morphology, structure and properties of the coatings were evaluated in relation to the electro-synthesis conditions. It was found that incorporation of SiC nanoparticles into the metal matrix produces morphological changes in the deposit. These are responsible for increases in the microhardness of the composite coatings and a better resistance against erosion–corrosion compared with pure nickel coatings. The increases in SiC nanoparticle content in the coating and the hydrodynamic conditions in the electroplating process cause grain refining and changes in the crystal growth of the nickel grains in the Ni deposit. As consequence of structural modification in the crystalline orientation of the Ni deposit, grain refining and strain occurred in the nickel lattice. These structural changes in the nickel deposit led to enhanced performance of the Ni–Sic composite coating in the erosion–corrosion test. Additionally, the presence of inert particles of SiC in the conductive matrix coating may have blocked the passage of the anodic Faradaic current, diminishing the corrosion rate of the coating.