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Aluminium metal matrix composites are used in automotive and aerospace industries because of their high performance and weight reduction benefits. The current investigation aims to focus on the development of the stir cast aluminium-boron carbide composites with enhanced mechanical and tribological properties.

The aluminium-boron carbide composites are produced by stir casting process. Aluminium alloy A356 is chosen as the matrix material and three sets of composites are produced with different weight fractions of boron carbide particles. Higher particle size (63 µm) of boron carbide is chosen as the reinforcement material. Aluminium-boron carbide composites are tested for mechanical and tribological properties. The effect of process parameters like load, speed and percentage of reinforcement on the wear rate are studied using the pin-on-disc method. The interaction of the process parameters with the wear rate is analysed by DesignExpert software using RSM methodology and desirability analysis. The coded levels for parameters for independent variables used in the experimental design are arranged according to the central composite design. The worn surface of the pin is examined using a scanning electron microscope. The phases and reaction products of the composites are identified by X-ray diffraction (XRD) analysis.

Aluminium-boron carbide composites reveal better mechanical properties compared to monolithic aluminium alloys. Mechanical properties improved with the addition of strontium-based master alloy Al10Sr. The ultimate tensile strength, hardness and compressive strength increase with an increase in the reinforcement content. The wettability of the boron carbide particles in the matrix improved with the addition of potassium flurotitanate to the melt. Uniform dispersion of particles into the alloy during melting is facilitated by the addition of magnesium. Wear resistance is optimal at 8 per cent of boron carbide with a load 20 N and sliding speed of 348 RPM. The wear rate is optimized by the numerical optimization method using desirability analysis. The amount of wear is less in Al-B₄C composites when compared to unreinforced aluminium alloy. The wear rate increases with an increase in load and decreases with the sliding speed. The wear resistance increases with an increase in the weight fraction of the boron carbide particles.

The produced Al-B₄C composites can retain properties at high temperature. It is used in nuclear and automotive products owing its high specific strength and stiffness. The main applications are neutron absorbers, armour plates, high-performance bicycles, brake pads, sand blasting nozzles and pump seals.

Al/B₄C composites have good potential in the development of wear-resistant products.

This study aims to develop the Al-Si-Mg metal matrix composite, reinforced distinctly with lime stone powder (LSP; 12% by weight) and Al₂O₃ (12% by weight), and compare their mechanical properties and tribological performance.

The composites are fabricated through stir casting process. In view of the previous work, the Al-LSP composite with LSP reinforcement (12 Wt.%) shows enhanced mechanical properties and tribological performance, as compared with other weight percentages.

Though the Al-LSP composite is less expensive, it shows similar hardness, tensile strength and specific strength, when compared with Al- Al₂O₃ composite. However, the Al-LSP composite exhibits significant enhancement of above three properties, when compared with Al-Si-Mg metal. The systematic factorial design of experiments is obtained through Taguchi OA [L9]. The tribological performance is estimated through wear rate (WR-mm³/m) and coefficient of friction (CF) by varying the operating parameters of sliding distance (SD), load (L) and sliding velocity (SV). According to ANOVA results, the optimal condition of WR for all the tested materials is L1SD3SV1. Further, the optimal condition of CF is L1SD1SV3 for Al-LSP and Al-Si-Mg metal, while L2SD3SV2 is for Al-Al₂O₃ composite. The regression equation predicts the measured experimental values within error band of ± 8 percentage.

A comparison of two composite materials (Al-LSP and Al-Al₂O₃) with same weight fractions (12%) shows almost same trend in both the mechanical and tribological testing process. However, the developed Al-LSP composite exhibited better properties than the Al-Al₂O₃ and Al-base. Therefore, Al-LSP can be suggested for automotive applications (i.e., connecting rod, cylinder liners, camshaft) and structural applications (such as frames, over hanging supports), without compromising in desirable original with properties of constituents in the new material, which is achievable for looking to the end uses.

The objective of this research is focused on the design of a new hybrid composite as well as to analyse the optimum turning conditions to minimise the surface roughness and work piece surface temperature, thereby increasing the productivity.

Mechanical properties such as hardness and tensile strength of Al-Si10Mg alloy reinforced with 3, 6 and 9 wt.% of alumina along with 3 wt.% of graphite prepared by stir casting method have been evaluated. The present study addresses the machinability parameter optimisation of Al alloy-9 per cent alumina-3 per centgraphite. Experiments were conducted based on the Taguchi parameter design by varying the feed (0.1, 0.15 and 0.2 mm/rev), cutting speed (200, 250 and 300 m/min) and depth of cut (0.5, 1.0 and 1.5 mm). The results were then analysed using analysis of variance (ANOVA).

Mechanical properties of the hybrid composite increases with reinforcement content. The surface roughness decreases with increasing cutting speed and conversely increases with increasing feed and depth of cut. The work piece surface temperature increases as cutting speed, feed and depth of cut increases. The ANOVA result reveals that feed plays a major role in minimising both surface roughness and surface temperature of work piece. The cutting speed and depth of cut follow feed in the order of importance, respectively.

The vibration of the machine tool is a factor which may contribute to poor quality characteristics. This factor has not taken been into account in this analysis since major vibrations in the machine are induced due to the machining process.

Design and development of new hybrid metal matrix composites (HMMCs) with a detailed analysis on machining conditions. The findings could help in the production of composite with a higher degree of surface finish. This will enable the adoption of HMMCs as industrial product for mass scale production.

Good quality characteristics were achieved using optimum machining conditions arrived using a statistical modelling.

Aluminium and its alloys are the most preferred material in aerospace and automotive industries because of their high strength-to-weight ratio. However, these alloys are found to be low wear resistance. Hence, the incorporation of ceramic particles with the aluminium alloy may be enhanced the mechanical and tribological properties. The purpose of this study is to optimize the specific wear rate and friction coefficient of titanium dioxide (TiO₂) reinforced AA7075 matrix composites. The four wear control factors are considered, i.e. reinforcement (Wt.%), applied load (N), sliding velocity (m/s) and sliding distance (m).

The composites were fabricated through stir casting route with varying weight percentages (0, 5, 10 and 15 Wt.%) of TiO₂ particulates. The mechanical properties of the composites were studied. The specific wear rate and friction coefficient of the newly prepared composites was determined by using a pin-on-disc apparatus under dry sliding conditions. Experiments were planned as per Taguchi’s L16 orthogonal design. Signal-to-noise ratio analysis was used to find the optimal combination of parameters.

The mechanical properties such as yield strength, tensile strength and hardness of the composites significantly improved with the addition of TiO₂ particles. The analysis of variance result shows that the applied load and reinforcement Wt.% are the most influencing parameters on specific wear rate and friction coefficient during dry sliding conditions. The scanning electron microscope morphology of the worn surface shows that TiO₂ particles protect the matrix from more removal of material at all conditions.

This paper provides a solution for optimal parameters on specific wear rate and friction coefficient of aluminium matrix composites (AMCs) using Taguchi methodology. The obtained results are useful in improving the wear resistance of the AA7075-TiO₂ composites.

Recent trends in material science show a considerable interest in the manufacturing of metal matrix composites to meet the stringent demands of lightweight, high strength and corrosion resistance. Aluminium is the popular matrix metal currently in vogue that can be reinforced with ceramic materials such as particulates to meet the desired property. The purpose of this paper is to fabricate hybrid metal matrix composites to improve the dry sliding wear resistance and to study of the effect of sliding speed, load and reinforcement (alumina and graphite) on wear properties, as well as its contact friction.

The present study addresses the dry sliding wear behaviour of Al‐Si10Mg alloy reinforced with 3, 6 and 9 wt% of alumina along with 3 wt% of graphite. Stir casting method was used to fabricate the composites. Mechanical properties such as hardness and tensile strength have been evaluated. A pin‐on‐disc wear test apparatus was used to evaluate the wear rate and coefficient of friction by varying the loads of 20, 30 and 40 N, sliding speeds of 1.5 m/s, 2.5 m/s and 3.5 m/s at a constant sliding distance of 2100 m.

Mechanical properties of hybrid metal matrix composites (HMMCs) have shown significant improvement. The wear rate and coefficient of friction for alloy and composites decreased with increase in sliding speed and increased with increase in applied load. Temperature rise during wearing process for monolithic alloy was larger than that of HMMCs and Al/9% Al₂O₃/3% Gr composite showing the minimum temperature rise.The worn surfaces of the composites were investigated using scanning electron microscope.

The paper shows that aluminium composites can improve strength and wear resistance.

HMMCs has proven to be useful in improving the dry sliding wear resistance.

Recent advances in modern technology have generated the need to develop newer materials for better antifriction and wear properties. The objective is to analyse the significance of design parameters that significantly affects the dry sliding wear.

The tribological behaviour of aluminium alloy (Al‐Si10Mg) reinforced with alumina and graphite produced by liquid metallurgy is studied using pin‐on‐disc wear test apparatus under dry sliding condition. Experiments are conducted based on the plan of experiments generated through Taguchi technique. A L27 Orthogonal array is selected for analysis of the data. Influence of applied load, sliding speed and weight percentage of reinforcements on wear rate as well as the coefficient of friction during wearing process is studied using analysis of variance technique and regression equations for each response are developed. Finally, confirmation tests are carried out to verify the experimental results.

Mechanical property such as hardness has been evaluated and it was found that the hardness increases as reinforcement content increases. The wear rate and coefficient of friction increases by increasing load and decreases by increasing sliding speed and weight percentage of reinforcements. Results from analysis of variance reveals that the applied load has the highest influence on both wear rate and coefficient of friction, followed by sliding speed and weight percentage of reinforcement.

Aluminium hybrid metal matrix composites showing ample success in improving strength and wear resistance by utilising the optimal process condition.

The results obtained by this method are useful in improving the dry sliding wear resistance.

The purpose of this paper is to investigate the friction and wear mechanisms in copper-based self-lubricating composites with MoS₂ as the lubricating phase, which provides a theoretical basis for subsequent research on high-performance copper-based self-lubricating materials.

Friction tests were performed at a speed of 100 r/min, a load of 10 N, a friction radius of 5 mm and a sliding speed of 30 min. Friction experiments were carried out at RT-500°C. The phase composition of the samples was characterized by X-ray diffraction of Cu Ka radiation, and the microstructure, morphology and elemental distribution were characterized by scanning electron microscopy and energy dispersive spectroscopy. Reactants and valences formed during the wear process were analyzed by X-ray photoelectron spectroscopy.

The addition of MoS₂ can effectively improve friction-reducing and anti-wear action of the matrix, which is beneficial to form a lubricating film on the sliding track. After analyzing different changing mechanism of the sliding tracks, the oxides and sulfides of MoS₂, MoO₂, Cu₂O, CuO and Ni(OH)₂ were detected to form a synergetic lubricating film on the sliding track, which is responsible for the excellent tribological properties from room to elevated temperature.

For self-lubrication Cu–Sn–Ni–MoS₂ material in engineering field, there are still few available references on high-temperature application.

This paper provides a theoretical basis for the following research on copper-based self-lubricating materials with high performance.

With this statement, the authors hereby certify that the manuscript is the results of their own effort and ability. They have indicated all quotes, citations and references. Furthermore, the authors have not submitted any essay, paper or thesis with similar content elsewhere. No conflict of interest exits in the submission of this manuscript.

This study aims to investigate the production and abrasive wear rate of functionally graded TiB₂/Al composites. TiB₂ particles have been spontaneously formed in liquid matrix using in situ technique. The properties of composites such as hardness, abrasive wear rate and microstructure have been examined.

In situ TiB₂ reinforcement phase was synthesized by using a liquid Al–Ti–B system. A semi-solid composite (Al_(l)-TiB_2(s)) prepared at 900°C was solidified under a centrifugal force to both grade functionally and give the final shape to materials. Abrasive wear test of materials was conducted using the pin-on-disk method at room temperature. The wear tests were carried out with two different loads of 1 Newton (N) and 2 N, a sliding velocity of 3.5 m s⁻¹ and a sliding distance of 75 m.

This research provided the following findings; TiB₂ particles can be successfully synthesized with in situ reaction technique in molten aluminum. It was determined that abrasive wear rate increases with increasing load and decreases with increasing TiB₂ reinforcement content within matrix.

In previous studies, there have been many trials on the in situ production of TiB₂-reinforced aluminum matrix composites. However, there are few studies on production of in situ TiB₂-reinforced aluminum matrix functionally graded materials. At the same time, there is no study that the properties of composite, such as hardness and abrasive wear rate, are examined together according to centrifugal force.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2019-0538/

The purpose of this paper is surface roughness prediction using pattern recognition for the aluminium hybrid metal matrix composite (HMMC).

Hybrid composites were manufactured using liquid metallurgy technique. The cast HMMC was machined using an industrial CNC turning centre and the machining vibration signals were acquired using an accelerometer. The acquired signals were processed and used to build a machine learning model for predicting surface finish based on the tool signature.

The authors established a technique for predicting and monitoring the surface quality during machining using a low cost accelerometer. It is capable of being integrated with the machine controller for online warning of deviations in surface roughness. The system is reconfigurable for any machining condition with a very short training period. The use of this model facilitates online surface roughness monitoring, avoiding the need for costly measuring equipment.

The model developed is innovative and not reported widely to the best of the authors' knowledge. The use of accelerometer‐based surface roughness prediction and control is an innovative approach for automation of machining process monitoring. These can be integrated into any existing machining centre as a standalone system or can be integrated into the CNC controller like Fanuc or Siemens.

This research aims to describe the influence of weight per cent of graphite (Gr), applied load and sliding speed on the wear behavior of aluminum (Al) alloy A356 reinforced with silicon carbide (SiC) (10 Wt.%) and Gr (1 Wt.% and 5 Wt.%) particles. The objective is to analyze the effect of the aforementioned parameters on a specific wear rate.

These hybrid composites are obtained by means of the compo-casting process. Tribological analyses were conducted on block-on-disc tribometer at three different loads (10, 20 and 30 N) and three different sliding speeds (0.25, 0.5 and 1 m/s), at the sliding distance of 900 m, in dry sliding wear conditions. Optimization of the tribological behavior was conducted via the Taguchi method, and ANOVA was used for the analysis of the specific wear rate. Confirmation tests are used to foresee and check the experimental results. Examined samples were analyzed via a scanning electron microscope (SEM). Regression models for predicting specific wear rate were developed with Taguchi and ANN (artificial neural network) methods.

The biggest impact on value of specific wear rate has the load (43.006%), while the impact of Wt.% Gr (31.514%) was less. After comparison of the results, i.e. regression models, for predicting the specific wear rate, it was observed that ANN was more efficient than the Taguchi method. The specific wear rate of Al alloy A356 with SiC (10 Wt.%) and Gr (1 Wt.% and 5 Wt.%) decreases with a decrease in the load and weight per cent of Gr-reinforcing material, as well as with a decrease in sliding speed.

The results obtained in this paper using the Taguchi method and the ANN method are useful for improving and further investigating the wear behavior of the SiC- and Gr-reinforced Al alloy A356.