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This study aims to investigate the friction behavior of SiC-B₄C composite ceramics treated by annealing in air sliding against SiC balls.

The dry sliding tests were performed with a ball-on-disk tribometer in ambient air condition. Analysis of friction coefficient, phase compositions of the surfaces, morphologies of worn surfaces of disks and wear scars of balls and surface profiles of wear tracks for disks were carried out using Raman spectroscope, microscope and surface profilometer.

The results show that a self-lubricating layer with the main composition of H₃BO₃ was successfully fabricated on the surface of SiC-B₄C composite ceramics by the annealing treatment in air. When the mass fraction of SiC is more than that of B₄C, SiC-B₄C composite ceramics show higher friction coefficients, the values of which are 0.38 for 80 Wt.%SiC-20 Wt.%B₄C and 0.72 for 60 Wt.%SiC-40 Wt.%B₄C, respectively. SiC-B₄C composite ceramics show lower friction coefficients when the mass fraction of B₄C is more than that of SiC. The low friction coefficients of 40 Wt.%SiC-60 Wt.% B₄C composite ceramics (0.16) and 20 Wt.%SiC-80 Wt.% B₄C composite ceramics (0.20) are attributed to the formation of a sufficient amount of H₃BO₃ layer, rather than the layer of silicon oxides.

This study will help to understand the friction behavior of SiC-B₄C composite ceramics with different ratios of SiC to B₄C treated by annealing in air.

The objective of the present investigation is to prepare a Zn–Al matrix (73 wt. per cent Zn + 27 wt. per cent Al) reinforced with SiC and graphite (Gr) hybrid composites by a rapid current sintering technique. Well-known Zn-based alloys are good candidates for load bearing applications. However, some limitations exist in Zn sublimation during casting and solid-state sintering and low-sliding velocity applications. The purpose is to develop new hybrid composites for self-lubricated bearing alloys by the facile production technique of current-activated sintering for these types of hybrid composites at very short sintering periods.

Designing a special power unit for current sintering. The hybrid composites of the Zn–Al matrix were reinforced with 20 vol. per cent SiC and different amounts of Gr (2.5, 5.0, 7.5 and 10 weight per cent) and sintered rapidly by current sintering. Tribological tests for wear behaviors and self-lubrication effect were studied. The authors' approach is mainly to produce low-cost load-bearing materials.

Successful and rapid production of Zn–Al alloy SiC/Gr hybrid composites in this study led to increasing load bearing capacity, decreasing friction coefficient and wear rate and production of good substitutes for conventional bearing applications.

A conventional Zn alloy was reinforced with both SiC and Gr particles. This work is original in two ways. It is noted after the literature survey that this alloy is first reinforced with two different types of reinforcements as a hybrid type of composite. Second, the consolidation of this hybrid material was carried out by a direct current for eliminating Zn sublimation and shortening the production time. In tribological applications demanding strength and lubrication requirements, Zn–Al/SiC/Gr hybrid composites were assessed as good substitutes for conventional materials owing to improved wear resistance as a result of combined reinforcement of SiC and Gr particulates.

Parts that are to be used in aircraft, satellites, automobiles and ships should have sound microstructure. Components made from AA6082/Si₃N₄ and AA6082/SiC composites are in demand from industries. Hence, these components are to be fabricated by suitable technique at the appropriate value of process parameters. The purpose of this paper is Microstructure analysis of AA6082/Si3N4 and AA6082/SiC composites

AA6082/Si₃N₄ and AA6082/SiC composites are successfully fabricated using the stir casting process. Their microstructures have been analyzed. This has been done at different magnification. The effect of the addition of Si₃N₄ and SiC particles in the 6082 aluminum alloy is investigated. Microstructure of AA6082/Si₃N₄ and AA6082/SiC composites are also compared. Results show that Si₃N₄ and SiC particles have good wettability with AA6082. These reinforcement particles are homogeneously distributed in the matrix of AA6082.

There are no adverse effects of reactions in the microstructure of AA6082/Si₃N₄ and AA6082/SiC composites. There is not much difference between the distribution and interfacial characteristics of Si₃N₄ and SiC particles. AA6082/Si₃N₄ and AA6082/SiC composites have good properties. This is high strength at low density. Due to which they become suitable for the aircraft and space industry. So far, SiC, Al₂O₃ and tungsten carbide have been mostly used as reinforcements with different grades of aluminum alloy.

Not much experimental work is found with Si₃N₄ and SiC particles as reinforcement with AA6082. The novelty of this research work is that an effort has been made to fabricate AA6082/Si₃N₄ and AA6082/SiC composites at such values of process parameters, by stir casting process, so that sound and defect free microstructure is obtained. Microstructure of AA6082/Si₃N₄ and AA6082/SiC composites is also compared, to find which is better.

The purpose of this study is to investigate the effect of the sintering temperature on the microstructural, mechanical and physical properties of Cu-SiC composites.

The powder metallurgy route was used to fabricate the samples. Cold compaction of powders was conducted at 250 MPa which was followed by sintering at 850°C–950°C at the interval of 50 °C in the open atmospheric furnace. SiC was used as a reinforcement and the volumetric fraction of the SiC was varied as 10%, 15% and 20%. The processed samples were metallurgically characterized by the scanning electron microscope (SEM). Mechanical characterization was done using tensile and Vickers’ micro-hardness testing to check the hardness and strength of the samples. Archimedes principle and Four-point collinear probe method were used to measure the density and electrical resistivity of the samples.

SEM micrograph reveals the uniform dispersion of the SiC particles in the Cu matrix element. The results revealed that the Hardness and tensile strength were improved due to the addition of SiC and were maximum for the samples sintered at 950 °C. The addition of SiC has also increased the electrical resistivity of the Cu-SiC composite and was lowest for Cu 100% while the relative density has shown the reverse trend. Further, it was found that the maximum hardness of 91.67 Hv and ultimate tensile strength of 312.93 MPa were found for Cu-20% SiC composite and the lowest electrical resistivity of 2.017 µ- Ω-cm was found for pure Cu sample sintered at 950 °C, and this temperature was concluded as the optimum sintering temperature.

The powder metallurgy route for the fabrication of the composites is a challenging task as the trapping of oxygen cannot be controlled during the compaction process as well as during the sintering process. So, a more intensive study is required to overcome these kinds of limitations.

As of the author’s best knowledge, no work has been reported on the effect of sintering temperature on the properties of the Cu-SiC composites which has huge potential in the industries.

Sound microstructure components are necessary for reliability and safety; hence, these components are used in aircraft, satellite, automobiles and ships, where many commercial alloys are not suitable. The paper aims to discuss this issue.

AA6082/Si₃N₄ and AA6082/SiC composites were fabricated using the stir-casting process considering 5, 10 and 15 vol.% of reinforcement particles. Density and porosity of AA6082/Si₃N₄ and AA6082/SiC composites were calculated. Characterization was done using an X-ray (EDX) detector, attached to SEM. The effect of addition of Si₃N₄ and SiC particulates in the AA6082 was investigated.

Results showed that Si₃N₄ and SiC particulates had good wettability with AA6082 and were uniformly distributed in AA6082 matrix. No adverse effects of reactions were noticed in the microstructure of AA6082/Si₃N₄ and AA6082/SiC composites.

AA6082 with more than 15 vol.% of Si₃N₄ and AA6082/SiC reinforcement particles do not find industrial application where high hardness and tensile strength are required.

Components made from AA6082/Si₃N₄ and AA6082/SiC composites find their application where high hardness with better tensile strength is required.

Naturally and locally available materials are utilized for fabrication.

Little work is available in the literature on fabrication and characterization of AA6082/Si₃N₄ and AA6082/SiC composites. The authors have identified the process parameters at which proper fabrication is done and sound microstructure is obtained.

In the current scenario, new materials are gaining popularity due to higher specific properties of strength and stiffness, increase in wear resistance, dimensional stability at higher temperature, etc. Subsequently, the need for precise machining has also been increased enormously. The purpose of this paper is to study the surface roughness during the turning of Al-10%SiC and Al-5%SiC-5%Gr composites under different cutting conditions.

Artificial neural network (ANN) has been effectively employed in solving problems with effortless computation in the areas such as fault diagnosis, process identification, property estimation, data smoothing and error filtering, product design and development, optimisation and estimation of activity coefficients. Response surface method is also used to analyse the problems involving a number of input parameters and their corresponding relationship between one or more measured dependent responses. Using Design Expert.8 evaluation software package, a simpler and more efficient statistical RSM model has been designed. RSM models are created by using 27 experimental data measurements obtained from different turning conditions of aluminium alloy composites.

In this work, the surface roughness during turning of Al-10%SiC and Al-5%SiC-5%Gr composites under different cutting conditions has been studied. The surface roughness value is proportional with the increase in feed rate and depth of cut while inversely proportional with the cutting speed. In all turning conditions, Al-10%SiC composite has lower surface roughness values than Al-5%SiC-5%Gr hybrid composite. An ANN and response surface models have been developed to predict the surface roughness of machined surface. The experimental results concur well with predicted models.

In the present trend, new materials are gaining popularity due to higher specific properties of strength and stiffness, increase in wear resistance, dimensional stability at higher temperature, etc. Subsequently, the need for precise machining has also been increased enormously. In this work, the surface roughness during turning of Al-10%SiC and Al-5%SiC-5%Gr composites under different cutting conditions has been studied.

Aluminium silicon carbide reinforced metal matrix composite (Al/SiC‐MMC) materials are rapidly replacing conventional materials in various automotive, aerospace and other industries. Accordingly, the need for accurate machining of composites has increased enormously. The present work analyzes the machining of Al/SiC composites for surface roughness. An empirical model has been developed to correlate the machining parameters and their interactions with surface roughness. Response surface regression and analysis of variance are used for making the model. The developed model can be effectively used to predict the surface roughness in machining Al/SiC‐MMC composites. The influences of different parameters in machining Al/SiC particulate composites have been analyzed through contour graphs and 3D plots.

The aim is to study the tribological behavior of dual particle size (DPS) and triple particle size (TPS) SiC reinforced aluminum alloy‐based metal matrix composites – MMCs (Al/SiC_p MMC).

Al‐MMCs with DPS and TPS of SiC were prepared using 20 wt% SiC and developed using stir‐casting process. The TPS composite consist of three different sizes of SiC and DPS composite consist of two different sizes of SiC. The tribological test was carried out using a pin‐on‐disc type tribo‐test machine under dry sliding condition.

The TPS composite exhibited better wear resistance properties compared to DPS composite. It is anticipated that when a composite is integrated with small, intermediate and large SiC particle sizes (which is known as TPS) within the same composite could be an effective method of optimizing the wear resistance properties of the developed material.

This study provides a way to enhance the tribological behavior of automotive tribo‐components such as brake rotor, piston, cylinder, etc.

This investigation compares the tribological behavior of DPS and TPS SiC reinforced aluminum MMCs.

Mechanical properties are highly sensitive to the microstructure, and these are indirectly related to solidification parameters and processing conditions. AA7075 possesses lightweight and excellent properties as structural material which can be optimized with SiCp addition and a good fabrication technique.

7000 series aluminium alloys exhibit the highest mechanical properties. They are used for high-strength structural applications such as aircraft parts and sporting goods. The desirable properties of these alloys are: low density, high stiffness, specific strength, good wear resistance and creep resistance. The focus of this work is to investigate the microstructure of composites formed by the dispersion of silicon carbide particles (SiC) into AA7075 by stir casting processes. 7075 Al alloy is reinforced with 10 and 15 wt.% SiCp of size 10–20 µm by stir casting process. The composites have been characterized by X-ray diffraction and scanning electron microscopy, differential thermal analysis and electron probe microscopic analysis.

SiCp distribution and interaction with AA7075 matrix have been studied. AA7075/10 wt.%/SiCp (10–20 µm) and AA7075/15 wt.%/SiCp (10–20 µm) composites microstructure showed excellent SiCp distribution into AA7075 matrix. In addition, no evidence of secondary chemical reactions has been observed in X-ray diffraction and electron probe microscopic analysis.

Little experimental work has been reported so far about effect of addition of 10 and 15 wt.% SiCp of size (10–20 µm) on the microstructure of 7075 Al alloy fabricated by stir casting process. The present investigation has been carried out to study the microstructure and carry out XRD, DTA and EPMA analysis of 7075 Al alloy, 10 and 15 wt.% SiCp of size (10–20 µm) composite and detect the interfacial reactions with the objective to minimize the formation of Al4C3.

The purpose of this paper is to study the wear behavior of as‐cast (AC) and heat treated (HT) triple particle size (TPS) silicon carbide (SiC) reinforced aluminum alloy‐based metal matrix composites (SiC_p/Al‐MMC).

Al‐MMCs were prepared using 20 vol.% SiC reinforcement into aluminum metal matrix and developed using a stir casting process. Stir casting is a primary process of composite production whereby the reinforcement ingredient material is incorporated into the molten metal by stirring. The TPS composite consist of SiC of three different sizes viz., coarse, intermediate, and fine. The solution heat treatment was done on AC composite at 540°C for 4 h followed by precipitation treatment. The wear test was carried out using a pin‐on‐disc type tribo‐test machine under dry sliding condition. A mathematical analysis was also done for power factor values based on wear and friction results. The wear morphology of the damaged surface was also studied using optical microscope and scanning electron microscope (SEM) in this investigation.

The test results showed that HT composite exhibited better wear resistance properties compared to AC composite. It is anticipated that heat treatment could be an effective method of optimizing the wear resistance properties of the developed Al‐MMC material.

This paper provides a way to enhance the wear behavior of automotive tribo‐components such as brake rotor (disc and drum), brake pad, piston cylinder, etc.

This paper compares the wear behavior of AC and HT TPS reinforced Al‐MMC material under dry sliding condition.