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This paper is designed to investigate the wear and mechanical characterization of metal matrix composites (MMCs) by using micro and nano SiC on Al to study the influence of micro/nano SiC on the properties of fabiricated composite. Micro and nanocomposites with 1-4% of SiCp were developed using stircasting processes. From the outcomes, an improved grain refinement of micro and nano-composites when compared to monolithic was seen from the microstructural study. It found that an increase in SiC particulates content caused enhanced mechanical properties. Though, nano SiC reinforced MMCs resulted in improved mechanical properties compared to micro sized SiC particulates reinforced MMCs. The wear study was evaluated for comparison of micro/nano MMCs. The investigation indicates that, wear resistance of nano composites is better as compared to micro-SiCp reinforced MMCs. Fractured surfaces were inspected by the SEM analysis to study the nature of fracture in the micro and nano composite samples. [ABSTRACT FROM AUTHOR]

Because of its improved formability, lower production costs, and mechanical properties, aluminum metal matrix composite is the highly intriguing engineering material. It can meet the needs of modern engineering applications used in the automotive, military, aerospace, and marine industries. Hybridization of reinforcement is adopted to develop tailor‐made properties of composites for specific application. In this study, Al‐B4C‐Gr hybrid composites were produced with varying graphene content (0.25, 0.50, 0.75, and 1 wt.%) and keeping boron carbide (10 wt.%) as constant, the effect of graphene proportion on the mechanical properties of produced composites was evaluated. It has been observed that increasing the Gr reinforcement particles in the synthesized composites improves the mechanical characteristics of the composites, such as raising the tensile strength to 215 Mpa and the hardness to 110 HV due to the presence and proper distribution of reinforcement in the matrix. When compared to the base alloy, the tensile strength and hardness of Al10B4C0.75Gr composites rose by 27.174% and 67.290%, respectively. The dry sliding wear behavior of Al‐10 wt.% B4C‐wt.%Gr hybrid composites confirms that graphene and B4C particles in the matrix increase the wear resistance of the produced MMCs. The each parameter such as sliding distance, sliding velocity and load has its influence toward the better wear resistance of the developed composites and were discussed. [ABSTRACT FROM AUTHOR]

The metal matrix composites are widely used in various engineering applications. The fabrication of MMCs with different wt. % of reinforcements helps to improve the mechanical and the wear properties. In this research work, different wt. % of ceramic reinforcements with Al-7075 alloy were used to fabricate the hybrid MMCs routed through liquid metallurgical technique. The hardness of the fabricated composites was measured using Vickers hardness tester. The obtained results revealed that the hardness values increased by increase in the wt. % of reinforcement. Wear behaviour of composites was studied using pin on disc wear test equipment under dry-sliding conditions. Experimental trials were carried out based on the Taguchi method. L27 OA (Orthogonal array) was used for investigation of the data. Effect of the wear parameters on the wear and coefficient of friction were studied using ANOVA technique. ANOVA results revealed that the wt. % of reinforcement has a substantial influence on wear loss and COF. Finally, the orthogonal array results were verified by conducting confirmatory tests. The wear mechanism of the worn-out surface was analysed using SEM and EDS analysis. [ABSTRACT FROM AUTHOR]

The main aim of this research work is to examine the impact of machining parameters on the tool wear, machining forces and surface quality in micro-machining of light weight titanium Gr-12 alloy using statistical technique. The Taguchi method has been efficiently used here to associate input variables and output response relationship and also to evaluate the parametric effects by ANOVA analysis. The test results using a linear regression model were correlated. The output results indicated that the depth of cut and speed of cutting have substantial effects on machining force, surface quality and tool wear. The obtained results have been confirmed through confirmation tests with less than 6% error value. It proves that the projected statistical approach is reliable, and is an optimization and typical model for prediction of micro milling parameters for titanium Gr-12 alloy. [ABSTRACT FROM AUTHOR]

Having Low density and being Light weight with better mechanical properties, aluminum is the most significant material and is universally used in highly critical applications like navy, aerospace and particularly in automotive applications. This research work is aimed to investigate the effect of micro and nano Al2O3 (Alumina Oxide) to aluminium (Al) on the mechanical and wear properties of the Al composites. The micro - nano composites with 1, 2, 3 and 4 % of Al2O3 particulates in Al are fabricated using stircasting processes. It was found that an increase of Al2O3 both as micro and nano particulates content resulted in improved hardness, enhanced tensile strength and high wear resistance. However, nano Al2O3 reinforced MMCs have better hardness, improved tensile strength and higher wear resistance as compared with micro-sized Al2O3 reinforced MMCs. Grain refinement of composite and nano composite materials as compared with pure Al were observed in the microscopic structures. Analysis of wornout surface and tensile fracture surface was studied by SEM analysis to examine the nature of wear and tensile fracture mode of composite samples. [ABSTRACT FROM AUTHOR]

The Al2O3-SiC reinforced Al7075 Metal Matrix Composite (MMCs) is fabricated through liquid metallurgical technique. Ceramic particulates were amalgamated into the aluminium alloy to achieve improved mechanical properties and wear resistance. Al-7075/Al2O3/SiC hybrid MMCs were produced by reinforcing 2%, 3%, 4% and 5% of Al2O3 and 3%, 5% and 7% of SiC particles. Microstructural analysis was carried out to evaluate the uniform dispersal of reinforcing particulates within the base matrix. The output results indicate that the mechanical properties of the hybrid MMCs are enhanced by increase the wt. % of ceramic particulates. Tensile fractography results show the internal fracture structure of the tensile test specimens in which the particulates fracture and pullouts were observed. The wear characteristics of developed composites are studied using the pin-on-disc apparatus. The high wear resistance is observed at 5% Al2O3 + 7% SiC reinforced MMCs. [ABSTRACT FROM AUTHOR]

The effects of SiC (Silicon Carbide) - Al2O3 (Aluminium Oxide) particle in the Al alloy on the mechanical and wear characteristics of stir-casted Composites have been reported. The Al7075 is reinforced with 2, 4, 6 and 8 wt. % of reinforcements (SiC + Al2O3) to manufacture the hybrid composite. Ceramic particulates were added into Al alloy to achieve the low wear rate and improved mechanical properties. Hardening of cast specimens was done at 480ºC for the duration of 2 hrs and the specimens were quenched into two different quenching media (water and ice cubes). Finally, age-hardening was carried out at the temperature of 160ºC for the duration of 4 hrs and cooled at room temperature. The tensile strength, hardness and wear behaviour of MMCs (metal matrix composites) were evaluated on the un-treated and heat treated composite. The tensile strength and hardness of MMCs increased by incorporating SiC-Al2O3 particulates. The wear behaviour of the MMCs containing SiC-Al2O3 particulates revealed high wear-resistance. The heat-treatment had considerably improved the properties when compared to the non-heat treated composites. The composites with the highest tensile strength, hardness and enhanced wear resistance were found in the composites quenched in ice cubes. Worn-out surfaces of the composite specimens were studied by using SEM (Scanning Electron Microscopy) and EDS (Electron Dispersion Spectroscopy) analyses. [ABSTRACT FROM AUTHOR]

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In this investigation, an attempt has been made to hardness and wear rate of Al7075 hybrid metal matrix composite reinforced with the hard ceramics like alumina (2, 4, and 6 wt.% of Al2O3) and silicon carbide (3, 6, and 9 wt.% of SiC) is fabricated by using stir casting method. The samples were aging at temperature of 140 ∘C, 160 ∘C and 180 ∘C and monitored by hardness test. Taguchi’s L27 Orthogonal array was used for optimizing the process parameters. The obtained results indicated that hardness increased with increasing reinforcement. A wear test was performed using pin-on disk apparatus at room temperature for constant load of 30N, at a fixed sliding speed of 1.66 m/s and wear resistance increased as the weight percentage of reinforcement increased. Scanning electron microscope (SEM) studies were carried out to evaluate the worn surface. From the analysis of variance (ANOVA), Al2O3 is the significant factor that affects the hardness and wear loss of hybrid composites followed by SiCp and heat treatment. Confirmatory test was performed for the optimized parameters and these results were within the acceptable range when compared with the experimental results. [ABSTRACT FROM AUTHOR]