Dispersed SiC Research Articles

Tribological performance and mechanism of the titanium fiber-SiC whisker hybrid reinforced aluminum matrix composites prepared by pressure infiltration

In this contribution, a Ti-6Al-4V fiber (Tif) and SiCw (SiCw) hybrid reinforced 5056 Al composites (Tif + SiCw/5056 Al) were fabricated, and the effects of SiC whisker contents on the microstructure, mechanical properties, and wear resistance were investigated. The mechanical properties and the hardness of the composites increased first and then decreased with the increase of SiCw contents. The optimal ratio of SiCw to titanium fibers is 3 wt%. The flexural strength of the optimal composites reached 533 MPa, and the fracture toughness reached 29.1 MPa • m1/2. Under a load of 40 N, compared with the Tif/5056 Al composites sample, the wear rate of the optimal composites sample decreased by 80.7%. The uniformly dispersed SiC whiskers promote the formation of a mechanical mixing layer (MML) on the friction surface; the wear mechanism mainly involves abrasive wear and adhesive wear.

Enhanced microstructures, mechanical properties, and machinability of high performance ADC12/SiC composites fabricated through the integration of a master pellet feeding approach and ultrasonication-assisted stir casting

Integrating ceramic particles into aluminum matrices poses significant challenges due to their limited wettability and high specific volume ratio. This research focused on developing ADC12/SiC aluminum composites with varying SiC concentrations (1.5, 2.5, and 3.5 wt%) through an innovative fabrication process. Initially, ADC12/SiC master pellets containing a high concentration of homogenously dispersed 1-μm SiC particles were produced. Subsequently, these master pellets were introduced into the molten ADC12 alloy, followed by the dispersion of SiC particles via stir casting assisted by ultrasonication. The study assessed the impact of SiC weight fractions on the microstructures, mechanical properties, and machinability of the fabricated composites. The results revealed significant microstructural improvements and a more even distribution of SiC reinforcement inside the ADC12 matrix after the application of this innovative processing method. Increased SiC concentration led to notable refinement of α-aluminum grains and eutectic Si, as well as a more uniform dispersion of intermetallic phases. Additionally, a substantial increase in tensile properties and hardness was observed with the increment of SiC content. Particularly, the ADC12/3.5 wt%SiC composite exhibited a 46.73% increase in hardness and notable enhancements in yield strength, ultimate tensile strength, and elongation, denoted as 201.7 MPa, 241.1 MPa, and 3.40%, respectively, as compared with those of the unreinforced ADC12 alloy. Moreover, the ADC12/SiC composites demonstrated reduced surface roughness compared to the unmodified ADC12 alloy, indicative of a superior surface finish. With the addition of a high SiC content, the chip morphology was observed to change from continuous to discontinuous following a turning operation.

Significant impact of carbon source on microstructure and water–oxygen corrosion behavior of Si–Y alloy modified SiC/SiC composite

This study investigated the influence of carbon source on the microstructure and water–oxygen corrosion behavior of Si–Y alloy modified SiC/SiC composites. The results indicated that incorporating a small-sized and diffusely distributed carbon source within the matrix not only facilitates the preparation of a highly dense matrix, but also enables a uniform dispersion of the reaction-generated SiC. Furthermore, with the assistance of residual Si–Y alloy, the dispersed SiC enhanced the matrix strength, leading to a stepwise fracture behavior of the composites. Yttrium silicate with a gradient structure formed around the dispersed SiC could effectively exert its water–oxygen corrosion resistance. After 100 h of water–oxygen corrosion test at 1300 °C, the flexural strength of the composites with this structure reached 416 MPa, with a retention rate of 85 %. Both bending strength and retention were found to be at a high level in the current research on matrix modification.

Enhancement of Plain Carbon Steels Corrosion by Heat Treatment of the Direct Electrodeposited Ni-P-SiC Deposit

The current study examined the effects of heat treatment on the microhardness and wear resistance of electrodeposited Ni-P-SiC coatings, as well as the effects of SiC particle concentrations on the coating's metallic continuous phase. Direct electrodeposition onto a low alloy steel electrode (0.40 C) was used to obtain the deposits. A modified Watt bath and pure nickel anode were used, and the material was heat treated for one hour at 400 °C. Using XRD and SEM methods, the Ni-P-SiC deposit was characterized. Additionally, the deposit's microhardness was assessed using the LECO, DM-400, both before and after heat treatment, with a 50g load. The results obtained indicate that the coating's deposition on the surface of low alloy steel and its impacts on the deposit coating crystal plane may be influenced by the applied current density. The SiC dispersion slightly improved as the bath's SiC content rose. The reduction in phosphor content of the deposited Ni-P-SiC coating as a result of the SiC particles being added to the Ni-P electrodeposition bath. The XRD data showed that crystalline Ni and Ni3P are formed as a result of the heat treatment procedure. As the SiC content in the electrodeposition bath and heat treatment procedure rises, so does the microhardness of the Ni-P-SiC deposit. Low alloy steel's resistance to erosion corrosion can be strengthened by the Ni-P-SiC.

Effect of temperature on the ability to synthesize SiC from rice husks

Agricultural production in Vietnam annually generates a substantial volume of by-products and waste, with rice husks constituting the predominant fraction. Due to their meager economic value, rice husks are typically deemed agricultural waste and are commonly disposed of through incineration or discharge into rivers, contributing significantly to environmental pollution. In this investigation, rice husks were employed as the principal raw material for synthesizing silicon carbide. A blend of rice husks and silica gel in a ratio of 1.4/1 was subjected to sintering in a CO2 environment within the temperature range of 800 °C–1300 °C for 30 min. The chemical composition of the resultant product post-pyrolysis was ascertained in accordance with the ISO 21068–2:2008 standard. The capacity for SiC formation was further assessed utilizing Fourier transform infrared spectroscopy and x-ray diffraction. The outcomes revealed that the optimal temperature for SiC synthesis was 1200 °C. The composition of the sample post-pyrolysis was determined as 20.4% SiC, 51.2% SiO2, and 26.4% C (%wt). The primary phase constituents encompass amorphous carbon, cristobalite, α-SiC, and β-SiC. Scanning Electron Microscopy/ Energy Dispersive x-ray imaging of the product at 1200 °C exhibited dispersed SiC crystals on a SiO2-C substrate. The presence of SiC suggests the potential application of the product as a wear-resistant material.

Multi-response optimization of input and output responses of multipass FSP of AA7050 with (SiC + TiB2) nanoparticles by response surface methodology

In this work, multi-response optimization of output and input responses of multipass friction stir processing (MPFSP) of AA7050 with (SiC + TiB2) nanoparticles by response surface methodology based on the center composite design and metallurgical characterization were analyzed, and the optimum parameters of the MPFSP were discussed. At high tool rotational speed (TRS) of 1100 rpm with 50% TiB2 and 100% SiC nanoparticles, maximum joint efficiency (137.80%) was observed due to uniformly dispersed SiC and TiB2 within the matrix, serving as practical obstacles to dislocation motion, hindering plastic deformation, and facilitating enhanced mechanical properties. MPFS and nanoparticles broke the coarse grain structure of the base metal and produced a fine and homogenous grain structure in the stir zone. Increasing the concentration of reinforcement particles and FSP passes (1 to 4) inhibited grain boundary migration and significantly reduced the high-angle grain boundary and grain size. The optimized value of input parameters TRS, TiB2 nanoparticles, and SiC nanoparticles was observed as 1068 rpm, 56%, and 97%, while the optimized value of output response tensile strength, % strain, and hardness value was found as 569.16 MPa, 20.79, and 148.32 HV respectively. The p-value for all three models remained below 0.05, indicating a confidence level exceeding 95% in the constructed models, rendering them suitable for design exploration. The hardness value range of MPFSP/(SiC + TiB2) lies between 130 HV and 190 HV. The minimum hardness value of 131.03 HV was observed at 0% TiB2 and 50% SiC reinforcement particles with TRS of 1100 rpm, while the highest microhardness (187.02 HV) was perceived at 1000 rpm.

Enhanced mechanical properties of nanocrystalline B4C–SiC composites by in-situ high pressure reactive sintering

A unique optimized of core–shell structural B4C nanopowder, sintering aid additive of Si, and high-pressure sintering technique has been used to process nanocrystalline B4C–SiC ceramics with enhanced mechanical properties. C-coated B4C nanopowder was initially uniformly mixed with micron Si of different content by ball-milling. B4C–SiC composites with a homogenous distribution of SiC in B4C matrix were subsequently obtained by sintering the mixed powders at 6 GPa and 1600 °C. The added Si reacted with submicron amorphous carbon layer and amorphous carbon nanoshell to form dispersed SiC nanocrystals and Si–C phase filled at B4C grain boundaries and pores, respectively. The prepared composite had the most outstanding mechanical properties when the Si content in the precursor was 15 wt%, with a hardness reaching 37.8 GPa and a fracture toughness reaching 7.3 MPa·m1/2. Microstructural characterizations indicated that the multi deflection of nanoscale crack caused by intergranular fracture, the covalent bonding of Si–C phase at the grain boundary, and the abundant nanotwin substructure were jointly responsible for the superior performance in hardness and fracture toughness.

On the microstructural and mechanical responses of dual-matrix Al-Ni/SiC composites manufactured using accumulative roll bonding

This article discusses the correlation between the microstructural and mechanical changes in the dual-matrix Al-Ni/SiC composites processed by Accumulative Roll Bonding (ARB) technique. Three different SiC concentrations, 1, 3, and 5% were considered to reinforce Al and Al-Ni dual-matrix composites. ARB process was applied up to 7 cycles to manufacture a composite with homogenous dispersion of the three phases. The results showed that the presence of Ni layer between Al and SiC particles enhanced the dispersion of SiC in the matrix, which positively affect the mechanical strength. The maximum tensile achieved was 257 MPa for composite containing 3 % SiC after 7 ARB cycles compared to 37.2 MPa for the AA1050. Increasing SiC content reduces the adhesion between Al and Ni layers, which reduces the elasticity of the composites. However, for the composites with 5% SiC, after 3 ARB cycles, the strength was reduced due to the cracking of the Ni layer caused by the stress concentration around the SiC particles. The hardness values of the ARBed AA1050, AA1050-Ni, and AA1050-Ni/5 wt% SiC are 85.5, 93.5, and 109.7, respectively, after 7 ARB cycles. In terms of strength, the samples with 3% SiC content showed the optimum stress enhancement with minimum reduction in the elongation, which achieve a compromised response for many applications.

Effect of Spark Plasma Sintering Temperature on Phase Evaluation and Mechanical Behaviour of cu- 4 Wt% SiC Composite

Spark plasma sintering (SPS) is a novel approach to fabricate Cu- SiC composites which have a relatively broad range of potential uses in space applications. The Cu- 4 wt% SiC composite with homogeneously dispersed SiC particles has been successfully synthesized at various SPS temperatures. In this study, the effect of SPS temperatures on the phase evaluation and mechanical characteristics of the Cu- 4 wt% SiC composite was investigated. From the results, it was confirmed that the optimum sintering temperature for Cu- 4 wt% SiC composite is 950°C. Raising the spark plasma sintering temperature from 850°C to 950°C led to a higher concentration of copper-liquid phase which accelerates the SiC particle rearrangement and fills the interstitial voids present in the interfaces of matrix and reinforcements which improves the mechanical properties of the Cu- 4 wt% SiC composite. However, increasing the SPS temperature by more than 950°C prone to the generation of the copper net and inhomogeneous SiC particle dispersion in the copper phases and declines the performance characteristics of the synthesized composite. The Cu- 4 wt% SiC composite sintered at 950°C exhibits superior mechanical characteristics than the composite sintered at 850°C, 900°C and 1000°C.

Isothermal and cyclic oxidation behavior of in-situ grown MoSi2-SiC coating on Mo substrate at 1300 °C

We prepared the in-situ grown composite coating layer on Mo substrate to improve the resistance of MoSi2 coating against cyclic oxidation by introducing SiC reinforcement to reduce the thermal expansion mismatch with Mo substrate. Composite coating of MoSi2–19.3 vol% SiC was fabricated using a two-step approach of Mo2C coating on Mo substrate followed by siliconizing to achieve uniform dispersion of nanosized SiC particles in a matrix of equiaxed MoSi2 grains. The superior performance of this coating over monolithic MoSi2 coating was clearly demonstrated through evaluations of bot its isothermal and cyclic oxidation behavior at 1300 °C. In both coatings, diffusion-limited growth of oxide film was observed as indicated by parabolic weight gain up to 100 h at 1300 °C. Slightly faster oxidation rate in this isothermal test was observed in the composite coating and mainly attributed to the fast oxygen transport through open pores and blowholes created by CO gas evolution from the internal oxidation of SiC particles. Composite coating gave rise to drastic improvement of cyclic oxidation resistance at 1300 °C while monolithic MoSi2 coating broke into pieces in less than 35 cycles. Both equiaxed grains of MoSi2 and SiC dispersion was effective in suppressing the occurrence of through-thickness cracks in coating layer due to lower thermal stress generated during cooling to room temperature.

Influence of various tool shoulder design on hybrid surface composite of AA7075-T651/SiC/graphene through friction stir processing

ABSTRACT In the recent work, tool shoulder designs such as flat shoulder (TFS), kurl shoulder (TKS), scroll shoulder (TSS), and knurling (TKNS) were creatively designed to improve the surface properties. The AA7075/SiC/Graphene hybrid surface composites were fabricated through friction stir processing using different shoulder designs. The influence of shoulder designs on microstructure, mechanical, tribological, and corrosion properties were examined. The material characterizations such as macrostructure, microstructure, particle dispersion, and elemental analysis were studied through optical microscopy and field emission scanning electron microscopy with energy-dispersive X-ray spectroscopy. The current study found that the dispersion of SiC and graphene particles inside the matrix fabricated by the TSS tool design was more uniform due to the tool shoulder feature, leading to improved material flow during stirring. The sample fabricated using the TSS tool displayed higher grain refinement, the smallest grain size, which was 3.5 μm. The TSS design effectively eliminated the cluster formation and obtained a defect-free composite resulting in greater hardness (197 HV), lower wear resistance (0.0038 mm3/m) and higher corrosion resistance (– 0.650 mV) compared to other tool designs. However, the lowest values of hardness, wear rate, and corrosion resistance were obtained by TFS design.

PRODUCTION OF FUNCTIONALLY GRADIENT MATERIALS BASED ON SILICON CARBIDE AND HIGH-ALLOY STEEL USING SPARK PLASMA SINTERING TECHNOLOGY

An important scientific task of practical materials science is the production of metal-ceramic composites in the form of functional gradient materials (FGM) for special-purpose products. In this regard, a study was conducted on the application of spark plasma sintering (IPS) technology for the effective diffusion connection of SiC ceramics and high-alloy steel (grade X18R15) to obtain a combined FGM composite. In a comprehensive experimental study, the dynamics of consolidation and changes in the phase composition of dispersed SiC under conditions of different temperatures and heating rates, pressing pressure, and holding time were studied. As a result, the IPS conditions were optimized for obtaining SiC ceramics of high relative density (82%) and microhardness (500 HV) of stable phase composition. The physicochemical foundations of the formation of a strong compound of a two-component SiC-ceramic and steel system under IPS conditions without additives and using a mixture of additives in the form of a binder, a reaction binder and a damper (Ti–Ag, Ti–TiH2, Ti–Ag–TiH2 and Ti–Ag/Mo additive systems) have been studied. The structure, composition of ceramics and intermediate (binding and damping) layers, as well as the diffusion of elements at the boundary of the formed compounds in FGM composites, were studied using XRF, SEM and EMF methods. It was found that the Ti–Ag/Mo additive in the ratio of 30 wt. % Ti–70 wt. % Ag and a dense layer of Mo (thickness ~ 2 mm), acting as a damper to compensate for the temperature coefficient of linear expansion, ensure the formation of a connected FGM composite of an integral shape. The presented studies have been implemented for the first time, are promising and require further development in order to gain scientific knowledge of the manufacture of composite products for special purposes.

背应力平衡策略实现非均质Al-SiC复合材料的强塑 性协同

Strength-ductility trade-off dilemma remains a significant obstacle to high-strength composites due to the undesirable dislocation storability. Herein, an ingenious nano-micro SiC-reinforced Al matrix composite (AMC) with heterogeneous grain structures of coarse and fine grains was designed via a novel deformation-driven metallurgy method. The accumulated geometrically necessary dislocations and the intragranularly dispersed SiC particles were tailored based on the principle of back stress amelioration, which was a key point to maintain the dynamic balance with the applied stress toward strength-ductility synergy. The ultimate tensile strength and uniform elongation of the designed SiC5np-5µp/Al composite reached 324 MPa and 12.9%, respectively, and the strength was 181% as high as that of the SiC10µp/Al with only 3% ductility loss. As such, a new strategy was provided herein to promote strength-ductility synergy via the further modified back stress.

Structure, composition, and preparation of thermal conductive composite materials based on polyurethane and modified silicon carbide particles

This paper presents the first data on the dependence of thermal conductivity of DFPCM on generalized parameters and type of structure, according to the classification (dilute – low filled – medium filled – high filled systems), using the system of polyurethane + modified silicon carbide particles as an example. New plasma-modified silicon carbide particles with a unique structure and high specific surface area have been obtained, and their main characteristics necessary for calculating the compositions, generalized parameters, and determining the type of disperse structure of DFPCM have been determined. The main regularities are established that describe the relationship between the thermal conductivity coefficient (λ pcm) and the generalized parameter Θ, the type of structure of the DFPCM, and the surface morphology of SiC particles. For the first time, the contribution of the specific surface area of dispersed SiC particles (S BET − from 3 to 45 m2/g) to the thermal conductivity of disperse systems is shown.

THE EFFECT OF SiC DISPERSED SILICON CARBIDES ON THE QUALITY AND MICROHARDNESS OF Ni‒P-COATINGS AFTER CRYSTALLIZATION ANNEALING

The effect of SiC dispersed silicon carbides SiC additive (1.0 g/l) on formation of high (more than 1000HV) microhardness and defectiveness of the nickel-phosphorus coating of the steel parts used in critical assemblies and mechanisms at transportation of oil and mineral oil was evaluated. It is established, that regardless of SiC presence in the structure, the coating crystallizes with formation of identical microhardness level. However, the addition of SiC can drastically reduce the heat treatment time especially on parts with significant weight-size characteristics. The presence of defects in the coating – cracks and pore chains, was established by the standard method of wetting the inspected surface with an indicator solution. It has been shown that if the steel composition has less than 0.5% nickel, there are no defects on the surface of the coated parts both after crystallization annealing and during the long-term operation. If the nickel concentration is greater than 1.5%, cracking will occur in the nickel-phosphorus coating during heat treatment, despite the presence of the dispersive SiC additive in the composition. The revealed regularities of SiC dispersed silicon carbides effect on the microhardness value formed at crystallization annealing allow recommending their use in order to reduce the production process. The refined classification of steels, which nickel-phosphorus coatings are applied due to their tendency to defects, has revealed the main criterion – the content of nickel in the composition. It turned out that than lower the concentration of nickel is, then lower the risk of defect formation in the coating.

Corrosion resistance of composite NI-P coatings in various aggressive media

The paper studies corrosion resistance in highly aggressive media of composite nickel-phosphorus coatings after isothermal annealing at different temperatures accompanied by crystallization. The phase composition of chemically deposited Ni-P coating containing about 1% dispersed SiC was analyzed. Gravimetric method was used to determine the mass loss of the samples as a result of daily exposure to various acids and in a solution of nitric acid with a concentration from 5 to 65%, which is extremely aggressive for Ni-P coatings. At each heat treatment, the steel witness samples were used to determine the microhardness by the Vickers method at a load of 100 g. The dependence of the parameters of the corrosion process on the presence of a dispersed additive and the phase composition of the coating has been established. At low holding times the dispersed phase exhibits a barrier effect reducing crystalline phosphide Ni3P formation during annealing and corrosion resistance; meanwhile, prolonged holding at lower temperatures produces about 70% Ni3P, stable high hardness values and improved corrosion resistance values. Lowering the coating heat treatment temperature in an oxidizing environment reduces the intensity of phosphorus burn-off from the surface and decreases all coating properties. The concentration of nitric acid in the solution at the level of 5-15% is critical and contributes to the dissolution of all coatings, regardless of their composition.The conducted research and revealed regularities made it possible to determine the contribution of the phase composition and presence of the dispersed additive to the formation of the main service characteristics of the nickel-phosphorus coatings - microhardness and resistance to aggressive media, as well as to determine the technological modes of heat treatment that allow the formation of optimum properties of products used in the oil and gas industry.

Influence of SiC dispersion and Ba(Sr) substitution on the thermoelectric properties of Ca3Co4O9+δ

Ca 3 Co 4 O 9+δ is a typical p -type thermoelectric oxide material with a low thermal conductivity. In this study, double-layered oxide samples Ca(Ba,Sr) 3 Co 4 O 9+δ dispersed with different SiC contents were obtained via the traditional solid phase reaction method. The effects of different elemental substitutions and SiC dispersion contents on the microstructure and thermoelectric properties of the samples were studied. The double optimisation of partial substitution of Ca-site atoms and SiC dispersion considerably improved the thermoelectric properties of Ca 3 Co 4 O 9+δ . Through the elemental substitution, the resistivity of the Ca 3 Co 4 O 9+δ material was reduced. Conversely, introducing an appropriate amount of SiC nanoparticles enhanced phonon scattering and was crucial in reducing its thermal conductivity. After double optimisations, the dimensionless thermoelectric figure of merit ( ZT ) values of both Ca 2.93 Sr 0.07 Co 4 O 9+δ + 0.1 wt% SiC and Ca 2.9 Ba 0.1 Co 4 O 9+δ + 0.1 wt% SiC achieved an optimum value of 0.25 at 923 K.

In-situ high temperature study of the long-term stability and dielectric properties of nanofluids based on TiO2 and SiC dispersions in natural ester oil at various concentrations

• sNF1 sample demonstrates the highest AC BDV during the whole range of ageing. • sNF3 and tNF3 show rapid lack of stability in both temperature conditions. • sNF samples are more stable than tNF samples at the whole range of ageing. • Paper impregnated with sNF1 shows higher resistance to PD by 40% for both cases. • Shallow trapping theory is used to explain the better performance of sNF1. Diverse types of nanoparticles dispersed in various mineral and natural oils are under systematic investigation over the last years, in an effort to develop insulating nanofluids towards enhancing the lifetime and improvement of the operation conditions of power transformers. The moderate stability of the nanofluids (NFs) is a major obstacle in advancing reliable solutions with strong application potential. Although typical stability studies, i.e. ageing against time at ambient conditions, have been undertaken, thermally-induced degradation of NFs are very scarce; whereas in-situ assessed stability and dielectric properties at temperatures similar to that of the operation conditions of a power transformer, have not yet been conducted. Here, we present a systematic study to evaluate in-situ the influence of high temperature on the stability loss of nanofluids and their dielectric properties. Two types of semi-conducting nanoparticles, an oxide (TiO 2 ) and a carbide (SiC) have been employed in conjunction to a natural ester oil, to prepare NFs at various concentrations. Two sets of experiments were run in parallel, where dynamic light scattering and electrical measurements (AC Breakdown Voltage of the nanofluids and Partial Discharge of insulating paper impregnated with them) were conducted at ambient temperature and at 90 °C. It has been found that all NFs showed increased dielectric properties under thermal ageing with respect to the NFs aged at room temperature. In addition, TiO 2 -based NFs experience accelerated ageing at high temperature, while the SiC-based NFs exhibit better stability in comparison to their TiO 2 -based counterparts, when compared at similar conditions of time and thermal ageing. The NF with 0.004% w/w SiC nanoparticles exhibits the best dielectric response and the longer time stability for both sets of experiments i.e., ageing under both ambient temperature and 90 °C. These results demonstrate that results obtained from ambient temperature stability and dielectric properties studies, cannot be generalized or extrapolated at higher temperatures, where power transformers typically operate.

Thermophysical study of glycerol/choline chloride deep eutectic solvent based nanofluids

Working fluids act as a core role in low-grade thermal energy transportation. Deep eutectic solvent (DES), as a novel environmental solvent, has good stability and environmentally friendly, suitable for a variety of heat exchange environment. It has been emerging in working fluids thanks to superior chemical stability, low vapor pressure and promising rheological properties. While, relatively poor thermal conduction efficiency hinders its practical use. Adding nanoparticles to the DES, which is also coined to be nanofluid, provides a facile way to enhance the thermal conductivity as well as other related thermophysical properties. In this article, glycerol/choline chloride (ChCl) DES based nanofluids were prepared by dispersion of nano-TiO2, Fe2O3, CuO, SiC and carbon. Viscosity and thermal conductivity (TC) were studied comprehensively as functions of testing temperature and mass fraction. The highest thermal conductivity was found to be increased by up to 4.23%. More importantly, specific heat capacity, the other key factor in energy transportation for working fluids were studied with respect to that of nano-additive and temperature, indicates that it could be effectively increased by 26.23% compared to that of pristine base solvent. Mechanistic study by means of a set of experimental ways reveals that hydrogen bond association between DES and nanoparticle is responsible for this specific heat capacity increment.

Wear behaviour of aluminium alloy 5083/SiC/fly ash inoculants based functional composites – optimization studies

The wear characteristics of Aluminium AA 5083/SiC/Fly Ash functional composites under different load conditions are an important aspect to assess the inoculation of Fly Ash for enhancing the functionality of the aluminium composites with respect to its tribological behaviour and its influence on wear properties. The present work is majorly aimed at the development of AA 5083/SiC functional composites inoculated with Fly Ash using stir casting method for different blends of the reinforcements (2.5, 5 & 7.5 wt%). The novelty of this research is majorly attributed to the incorporation of functional inoculants in the form of Fly Ash, which along with the SiC is bound to influence the tribological characteristics of the composites. The wear characteristics of these fabricated composites have been investigated considering various process parameters viz., the load, sliding distance, sliding velocity, wt% of SiC and wt% of Fly Ash, based on the operational requirements of the composites in real time considered from the earlier research studies and the influence of each parameter on the wear rate is discussed. Based on the different wear regimes obtained after characterization of the samples at different load conditions, Analysis of Variance (ANOVA) is carried out for each blend of the samples to statistically validate the experimental outcomes. The results have given sufficient substantiation to the fact that wear rate decreases with the inoculation. The wear rate and coefficient of friction (COF) is minimum viz., 0.00095 mm3/m, and 0.301 respectively for L9 experimental trial, i.e., for the composite specimens synthesized by reinforcing 7.5 wt% SiC, and 7.5 wt% Fly Ash for a load of 20 N, sliding velocity of 6 m s−1, and a sliding distance of 3000 m. The results have conferred that micro segregation (coring) of SiC and uniform dispersion of Fly Ash in the matrix enhances its tribological characteristics.