Silicon Carbide Particle Size Research Articles

Multi-objective optimization of drilling of Al5059-SiC-2%MoS2 composites using NSGA-II

Abstract The drilling process is a broadly renowned conventional machining process which has the capacity to produce a hole on the components. The aluminum alloy of A15059 matrix is reinforced with the two different reinforcement particles such as silicon carbide (SiC) and molybdenum disulphide (MoS2). SiC particles are varied at three different sizes such as 10, 20 and 40 µm and three different weight percentages such as 5, 10 and 15%. MoS2 is added in all composites at a constant level of 2 wt%. The input process parameters considered for this investigation are spindle speed, feed rate, the particle size of SiC and weight percentage of SiC and output parameters such as metal removal rate (MRR) and temperature are studied. The present work is to optimize the drilling parameters of aluminium metal matrix composites using Non-dominated sorting genetic algorithm II (NSGA-II) technique. The drilling experiments are conducted based on Taguchi L27 orthogonal design. At the end, the optimal setting of drilling process parameters is found using NSGA-II that simultaneously maximizes MRR and minimizes temperature. The set of Pareto-optimal front offers flexibility to the manufacturing industries to select better drilling conditions depending on applications.

Silicon Carbide Films Prepared by Silicon Nitride Evaporation

Silicon carbide (SiC) films were synthesized on graphite substrates using silicon nitride (Si3N4) as silicon source at 1850°C, 1950°C, 2050°C and 2150°C, respectively. The characteristics of the synthesized films were analyzed by X-ray diffraction and scanning electron microscopy. The results show that the synthesis reaction can take place above 1850°C, and the SiC films were β-SiC. With the increase of temperature, the size of SiC particles increases, and when the soaking time is too short, the SiC particles are connected in a large area. Through the analysis of the films synthesis process, it is inferred that the growth of the SiC films belongs to the gas-solid growth mechanism.

Effect of manufacturing process parameters on the wear rate of Al 6061–Cu–SiCp alloy composites

In selecting the raw material for the production of machine parts, its wear resistance is considered a key parameter. Stir casting is a highly economical and effective technique for the manufacture of metal matrix composites. In the present research work, the tribological characteristics of an aluminum (Al) 6061 alloy composite reinforced with varying particle sizes of silicon carbide (SiC) (45, 53 and 63 μm) were investigated using a pin-on-disk wear-testing machine. Apart from this, the influence of pouring temperature and stirring speed during stir casting is also taken into account while characterizing the composite’s wear behavior. The analysis of variance test results indicate that the particle size of the silicon carbide reinforcement affects the wear rate of the composite samples. It was observed that the combined effect of stirring speed and pouring temperature significantly influences the wear rate of the test samples. Nevertheless, the combined effect of stirring speed and particle size of the ceramic reinforcement, as well as pouring temperature and particle size of silicon carbide, has no significance as far as the wear rate is concerned. The microstructural study of the worn samples was conducted using scanning electron microscopy analysis.

Synthesis of SiC Nanoparticles on Aluminum Metal Using a Dense Plasma Focus

Abstract: Synthesis of silicon carbide (SiC) nanoparticles was carried out using dense plasma focus technology with great potential for future industrial applications. The present work presents the synthesis and coating of aluminum metal with SiC nanoparticles using silica gel and acetylene gas. It also discusses the effects of molar ratio as well as the number of deposition shots on synthesis of SiC by dense plasma focus technology. The experimental results showed that SiC nanoparticles could be synthesized by the dense plasma focus technique. The SEM investigations showed a smooth surface with an average size of SiC particles of less than 1 μm with a SiC fiber-like microstructure.

Experimental investigation on the effect of SiC particles in machining process of Al–5.3%CU-SiCp–Al2O3p hybrid nanocomposite by EDM

In this study, the EDM process was used to investigate the machining properties of Al–5.3% CU–SiCp–Al2O3p aluminum composite, including SR, MRR, and TWR. Input parameters consist of two electrical and non-electrical category which relates to EDM settings and the composite variables including volume fraction and size of silicon carbide particles in nano and micro scale. SEM and TEM were used to investigate particles and the base metal. Surface roughness measurement device and ball milling was used to measure and make MMC. The results show that increasing the volume fraction and the size of the reinforcing particles led to decrease in the material removing rate, and increasing in TWR and SR. During electrical discharge machining of Al-MMC with 5% SiC reinforcement, reducing the particle size from 40 μm to 100 nm resulted in approximately a four-fold increase in the material removing rate and 25% reduction in the tool wear. Besides, SR in 5 vol% aluminum composite samples consisting of 100 nm size particles has improved the surface quality for approximately five times in comparison with that of 20 vol% aluminum composite samples with 40 μm the particle size.

Optimization of processing parameters, physical and mechanical properties of SiC – CNF composites using Taguchi approach

Abstract Silicon carbide (SiC) based composite with the low specific weight, the high specific strength over a large temperature range, and their great damage tolerance compared to their monolithic counterpart make them extremely useful as a high temperature load bearing material for many advanced applications. However, the reliability of these highly tough fibre containing composites pose a problem in actual use unless consistent material properties are maintained by adopting optimized processing parameters. In this study an attempts have been made to develop carbon nanofibers (CNF) dispersed thin SiC tubes used in applications like nuclear industries, power industry, semiconductor industry, chemical and paper industries etc. The material properties of the composite tubes were optimized through design of experiments to optimize the parameters like sintering temperature, heating rate, holding time and at different CNF compositions by using Taguchi experimental design method with an L9 (3^4) orthogonal array. Further, experiments were designed at the optimized processing conditions to evaluate the effect of particle size of SiC and CNF loading on properties of SiC-CNF composites by choosing an L9 (3^3) orthogonal array of design. The experimental results i.e. performance parameters were analysed by Taguchi optimization method and microstructure analysis. The effect of variables on the properties of the composites were studied from the signal to noise ratio (S/N), analysis of variance (ANOVA), and interaction plots. Processing at optimized conditions through design of experiments resulted in obtaining best properties when the values mentioned in parenthesis for the respective processing parameters like sintering temperature (2150°C), heating rate (8°C/min) and holding time (1hr) were maintained. SiC based composite with 1wt% CNF loading was identified to be the best homogeneous composite with superior properties at optimized design parameters. Thin composite tubes with wall thickness around 1mm with superior properties having density - 3.21g/cc, hardness - 26.5 GPa, fracture toughness - 5.12 MPam1/2respectively were than fabricated for further use in nuclear applications.

Preparation of Silicon Carbide porous Ceramics

Preparation of Silicon Carbide (SiC) porous ceramics with different sizes of SiC powders as raw material.The effects of reaction temperature and particle size on porosity, pore size distribution and flexural strength of SiC porous ceramics were studied. The results show that: Using SiC labeled F600 as raw material, when the sintering temperature is 2200 oC, the SiC porous ceramics have the best properties, the average pore size is 2.48 μm, the pore size distribution is uniform, the porosity can reach 53.75 % and the flexural strength is 21.23 Mpa. The maximum pore size distribution of SiC porous ceramics is proportional to the particle size of SiC, and the average pore size is linearly related to the median diameter of the raw material.

Study on Precision Polishing of Alumina Ceramics

The research is mainly to investigate the surface roughness by the mechanical polishing for the processing of alumina ceramic materials. In the experiment, the ceramic test piece was placed between the ceramic work ring and the grinding disc and then grinded firstly with an alumina grinding slurry with a particle size of 10 μm to make the original roughness of the test piece reach Ra value of 1.49 μm. Then the silicon carbide slurry polishing was employed to conduct the experiments by changing the concentration of the polishing, particle size, load, rotation and time to observe the polishing effect of ceramic materials under different parameters. The results showed that the silicon carbide particle size of 2μm, with the polishing time of 50 min, the disc speed of 90 rpm, the concentration of 35%, the original surface roughness of alumina ceramic Ra 1.49μm could be downed to 0.22 μm. The improvement rate could reach 94%. And the greater the specimen load with the better grinding efficiency, the smaller the load caused worse cutting force between alumina and the specimen surface. However, the better the surface roughness when the time kept going. Furthermore, alumina ceramic test piece after precision mechanical polishing by 3D surface roughness profiler and scanning electron microscope (SEM) analysis, the observation found that the wave of the original test piece rugged, after grinding and polishing wave front and grinding scratches had been removed, and a smooth surface was obtained.

Influence of a few important parameters on the rheological behaviour of silicon carbide nanoparticles dispersed aqueous suspension

In this study, investigations have been carried out on the effect of a few important parameters such as molecular weight and concentration of dispersant (polyethyleneimine) as well as that of pH on the rheological behaviour of aqueous suspension comprising silicon carbide (SiC) nanoparticles. In addition to this, the effect of particle size and addition of finer SiC particles on the rheological behaviour of SiC suspension have been examined. It is observed that viscosity of suspension increases with the increase in molecular weight of dispersant and decreases as the concentration of dispersant increases. Further, it is noticed that viscosity of the suspension progressively increases below the pH ≈ 7.6 and above the pH ≈ 9.3, indicating that minimum viscosity i.e. maximum stabilization of suspension is obtained within the pH range of ≈ 7.6–9.3. It has been observed that variation of SiC particle size from submicrometer to nanometer range and addition of nanometric SiC powder in SiC suspension containing coarser particles increase the viscosity significantly.

Dry Sliding Wear Behaviour of Aluminium 5059/SiC/MoS2 Hybrid Metal Matrix Composites

The present study is to investigate the influence of weight percentage of silicon carbide (SiC) (5,10 %, 15%) and particle size (10,20,40µm) of SiC and constant 2% of Molybdenum disulphide(MoS2)is reinforced with aluminium matrix. Wear performance of the composite was carried out through pin-on-disc method to calculate friction coefficient and wear resistance of the composites. The experiments were conducted by varying the sliding speed of (1.5,2.5 &3.5 m/s), loads (30,50&70N) with sliding distance ranges from (500, 1000& 1500m) under dry sliding conditions. Taguchi plan of experiments and ANOVA method was carried out to find the outcome of reinforcement ceramic particles, sliding distance, sliding speed, and applied load over the friction coefficient and wear rate. The result reveals that applied load and sliding distance are the most influencing factors for friction coefficient. Load and percentage of SiC indicates the most affecting factor for wear rate. Worn out surface of the composites were studied by optical microscopic image and Gwyddion software. To conclude, it was interfered that 15% weight percentage of SiC at 10µm offers better wear resistance and friction coefficient in AHMMCs.

Optimisation of testing parameters on two-body abrasive wear behaviour of nano-oMMT filled carbon-epoxy composites based on the Taguchi method

Two-body abrasive wear behaviour of carbon fabric reinforced epoxy (C-E) composites and nanosized organo modified montmorillonite (oMMT) particles dispersed C-E hybrid composites was investigated. Abrasive wear tests were carried out using a pin-on-disc machine under multi-pass condition. Silicon carbide (SiC) waterproof abrasive papers of different particle sizes were used under dry abrasion conditions. The influence of tribological parameters like applied normal load, abrading distance, filler loading and particle size of the SiC abrasives on the wear volume was investigated. Routine experimental results indicate that the wear volume depends on wt % of oMMT loading and the specific wear rate decreases with increase of abrading distance and increases with increasing load for all the composites. The scanning electron microscopy pictures indicate the reasons for failure of composites and influencing parameters. The orthogonal array, signal-to-noise ratio and analysis of variance were employed to study the optimal testing parameters on oMMT filled carbon-epoxy composites with 20 µm and 40 µm SiC particle sizes. The experimental results demonstrate that the abrading distance was the major parameter on abrasive wear, followed by filler loading and applied normal load. The particle size of SiC, however, was found to have a neglecting effect. Moreover, the optimal combination of the testing parameters could be predicted. Regression analysis was used to arrive at a mathematical model to predict the wear volume in terms of tribological parameters. The predicted wear volume of the composites was found to lie close to the experimental values.

The stab resistance of fabrics impregnated with shear thickening fluids including various particle size of additives

Shear thickening fluid (STF) treated high performance fabrics have attracted much attention in the applications of body protection. In order to improve the contribution of STF treatments, we designed multi-phase STFs and investigated the stab resistance of fabrics impregnated with these novel fluids. Silica and polyethylene glycol (PEG) based STFs were synthesized with various particle size of silicon carbide (SiC) additives to constitute the multi-phase suspension systems. The influence of the additive particles on the thickening behavior of the STFs was analyzed via rheological testing. The stab resistance of the fabrics was investigated in a drop tower against spike and knife threats and therefore, the role of the STFs was discussed in detail. According to this study, multi-phase STFs realized further improvement in the stab resistance of fabrics with respect to single-phase STFs.

Effect of silicon carbide particle size on microstructure and properties of a coating layer on steel produced by TIG technique

Surface engineering is essential to prolong life of engineering components subjected to deterioration in service from wear, erosion or corrosion, separately or in combination. This is possible by, for example, incorporating ceramic particles into a molten substrate surface, which may result in the partial or complete dissolution of the particles, and precipitation of a new phase, giving enhanced surface protection. Here, a single-track surface zone of a microalloyed steel was preplaced with a layer of SiC particles 1 and 75 μm in size, melted at a constant heat input with a tungsten inert gas torch using argon as shielding gas. The aim was to compare the melted track without SiC particles and when using SiC particles on the generated temperature, microstructure, melt dimension and hardness of the re-solidified surfaces. Previous work has shown that microstructural changes occur along the track length due to preheating of the un-melted surface ahead of the molten zone. This effect was explored by inserting thermocouples along the 300-mm length of steel. By optimising the process parameters, a re-solidified melt layer free of porosity has been achieved with 75-μm sized SiC particles. This melt reached a maximum hardness of 750 HV.

Influence of sintering temperature, SiC particle size and Y2O3 addition on the densification, microstructure and oxidation resistance of ZrB2–SiC ceramics

The influence of sintering temperature, silicon carbide particle size (50–60nm, 0.9μm and 44μm) and yttrium oxide addition on oxidation behaviour of ZrB2–SiC ceramics was investigated up to 1650°C in static atmosphere. Weight changes were measured and the thickness of formed oxide layer was evaluated by the light and scanning electron microscopy. Results show enhanced oxidation resistance of ZrB2–SiC composites sintered at 1750°C in spite of their lower density (∼93.2%) due to the grain growth cessation resulting in the refinement of microstructure. Similarly the oxidation resistance was also enhanced by refinement of microstructure due the submicron or nano-sized starting SiC powders. The addition of Y2O3 caused desired stabilization of cubic ZrO2 phase; nevertheless the oxidation resistance of Y2O3 doped samples was inferior in comparison to the basic material at oxidation temperatures exceeding 1500°C.

Influence of the Grit size of Silicon Carbide Particles on the Mechanical and Electrical Properties of Stir Casting Aluminum Matrix Composite Material

This paper studies the influence of the grit size of silicon carbide particles on the mechanical and electrical properties of stir cast aluminum matrix composites. A two step-mixing method of stir casting technique at (500 rpm) has been adopted. Type 1170 Al with (99.66 % C.P) and silicon carbide (SiC) particulates of 240 grit size (45 µm), 320 grit size (29 µm), 600 grit size (9 µm) and 1200 grit size (3 µm) were used. The incorporation of weight fraction of SiC ranges from 2.5 %, 5 %, 7.5 % and 10 %. The microstructures of the produced composites were examined using a scanning electron microscope. Mechanical properties were determined by using a universal testing machine of 30 KN load. Microhardness was performed on the composite specimens by using a LECO 700 HT tester with a load of 492.3 N and with a dwell time of 10 seconds. The electrical properties were determined using a Keithley instrument Model 2400 point probe machine. The results show that the modulus, yield strength and hardness of the composite increase at lower grit sizes of silicon carbide of 3 micron. The maximum hardness of 26.1 HVN and maximum modulus elasticity of 1517.6 N/mm -2 was obtained at 7.5 % weight fraction of SiC. A boost in the mechanical and electrical properties of the produced alloys was gained by changing the grit size of the silicon carbide.

Gas permeability and adsorbability of the glass-bonded porous silicon carbide ceramics with controlled pore size

Glass-bonded porous silicon carbide ceramics were fabricated by conventional method. The porosity and pore size could be tailored by changing the glass content and particle size of silicon carbide starting powder. The influence of microstructure on the gas permeability and the adsorption force between chucking work-pieces and porous SiC ceramic vacuum chuck was investigated. The permeability increased with the increase of porosity and average pore diameter. High permeability (1.45–6.53×10−12m2) of the porous SiC ceramics with a porosity of 32.1–64.7% could be achieved. Compared with porosity, pore size had a dominant effect on the permeability and adsorption force. The samples with the same porosity but smaller average pore size exhibited lower permeability and much higher adsorption force. The adsorption force of porous SiC ceramics was dependent on both microstructure and permeability. The P1000V70 sample with a pressure drop (ΔP) of 0.055MPa and permeability of 1.94×10−12m2 exhibited the highest adsorption force of 196N/cm2.

Effect of silicon carbide particle size and CaO content on foaming properties during firing and microstructure of porcelain ceramics

Porcelain green bodies were prepared using porcelain stoneware tile powder as the major raw material, with silicon carbide (SiC) and CaO as additives. These were fired at 1000–1200°C. The effects of SiC particle size and CaO content on the microstructure and foaming properties of porcelain ceramics were investigated in detail, with a view to further clarify the dominant factors linking foaming behavior to SiC oxidation during firing of a porcelain tile matrix. The results reveal that the size of the SiC particles has a significant influence on the number, size, and interconnectivity of the pores formed in the samples; this effect becomes more pronounced as the SiC particle size is reduced. The addition of a small amount of CaO is shown to significantly accelerate the foaming of a porcelain green body containing SiC, but this effect is gradually inhibited by an increasing formation of anorthite. Finally, the foaming mechanism is also discussed in detail.

Fabrication and Mechanical Properties of SiCw(p)/SiC-Si Composites by Liquid Si Infiltration using Pyrolysed Rice Husks and SiC Powders as Precursors

Dense silicon carbide (SiC) matrix composites with SiC whiskers and particles as reinforcement were prepared by infiltrating molten Si at 1550 °C into porous preforms composed of pyrolysed rice husks (RHs) and extra added SiC powder in different ratios. The Vickers hardness of the composites showed an increase from 18.6 to 21.3 GPa when the amount of SiC added in the preforms was 20% (w/w), and then decreased to 17.3 GPa with the increase of SiC added in the preforms up to 80% (w/w). The values of flexural strength of the composites initially decreased when 20% (w/w) SiC was added in the preform and then increased to 587 MPa when the SiC concentration reached 80% (w/w). The refinement of SiC particle sizes and the improvement of the microstructure in particle distribution of the composites due to the addition of external SiC played an effective role in improving the mechanical properties of the composites.

In vitro cellular responses to silicon carbide particles manufactured through the Acheson process: Impact of physico-chemical features on pro-inflammatory and pro-oxidative effects

Silicon carbide (SiC) an industrial-scale product manufactured through the Acheson process, is largely employed in various applications. Its toxicity has been poorly investigated. Our study aims at characterizing the physico-chemical features and the in vitro impact on biological activity of five manufactured SiC powders: two coarse powders (SiC C1/C2), two fine powders (SiC F1/F2) and a powder rich in iron impurities (SiC I). RAW 264.7 macrophages were exposed to the different SiC particles and the cellular responses were evaluated. Contrary to what happens with silica, no SiC cytotoxicity was observed but pro-oxidative and pro-inflammatory responses of variable intensity were evidenced. Oxidative stress (H2O2 production) appeared related to SiC particle size, while iron level regulated pro-inflammatory response (TNFα production). To investigate the impact of surface reactivity on the biological responses, coarse SiC C1 and fine SiC F1 powders were submitted to different thermal treatments (650–1400°C) in order to alter the oxidation state of the particle surface. At 1400°C a decrease in TNFα production and an increase in HO, COO− radicals production were observed in correlation with the formation of a surface layer of crystalline silica. Finally, a strong correlation was observed between surface oxidation state and in vitro toxicity.

Effect of Reinforcement Particle Size on Fabrication and Properties of Composite Coatings

In this work, three nickel-cobalt-phosphorus composite coatings co-deposited with particles of silicon carbide of three different sizes (40, 200, and 800 nm) were prepared on aluminum alloys using electroless deposition. The fabrication process of composites has been discussed, and the effect of the particle size of silicon carbide on microhardness and corrosion resistance of composites has been studied. The morphology, composition, microstructure, microhardness, and corrosion resistance of deposits were characterized by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, Vickers hardometer, and electrochemical workstation, respectively. The results reveal that the particle size has not much effect on the deposition rate of coatings; however, the coating codeposited with smaller particles has greater incorporation amount of particles in number density, less porosity, and finer grains. Furthermore, the incorporation of smaller particles leads to higher hardness and better corrosion resistance of coatings.