Applied Mechanics and Materials Vols. 766-767

Abstract: Nowadays, the usage of metal matrix composites is increased in aero space, automotive, marine, electronic and manufacturing industries. Aluminum metal matrix composites have attained significant attention due to their good mechanical properties like strength, stiffness, abrasion and impact resistant, corrosion resistance. When compared to the conventional materials Aluminum Silicon Carbide (AlSiC) hybrid materials available in minimum cost. In the present study, based on the literature review, the individual Silicon Carbide with aluminum and combined influence of Silicon Carbide with graphite reinforcements Aluminium Metal Matrix Composites and Silicon Carbide with mica reinforcement Aluminum is studied. The monolithic composite materials are combined in different compositions by stir casting fabrication techniques, to produce composite materials. The literature review framework in this paper provides a clear overview of the usage of Graphite and Mica as a reinforcing agent in different composition matrices along with its distinctive performances.

Abstract: Metal matrix composites are the resultant of combination of two or more elements or compounds, possessing enhanced characteristics than the individual constituents present in them. This paper deals with the fabrication of Al 2014-SiC composite and investigation of its Microstructure and Mechanical properties. 2014 Aluminium alloy is characterized by good hardness. It is selected as the base metal. The Silicon Carbide is characterized by good strength and low density (3.21 g/cm³). It is chosen as the reinforcement. Silicon Carbide is coated with Nickel by electroless method to increase its wettability and binding properties. The fabrication of metal matrix composites is done by stir casting in a furnace, by introducing the required quantities of reinforcement into molten Aluminium alloy. The reinforcement and alloy is mixed by means of stirring, with the help of a stirrer. The base alloy and the composites are then tested for mechanical properties such as tensile strength, flexural strength, impact strength and hardness. The fabricated samples have higher tensile strength and impact strength than the alloy. Microstructure of the samples, are analyzed using optical microscope.

Abstract: In the present study, the experimental results of the mechanical properties of Al6061-Graphite composites presented. The composites containing 6 to 9 wt% of graphite in steps of 3 wt% were prepared using liquid metallurgy route in particular stir casting technique. For each composite, reinforcement particles were preheated to a temperature of 250°C and then dispersed in steps of two into the vortex of molten Al6061 alloy to improve the wettability and distribution. Microstructural characterization was investigated by optical and scanning electron microscopy. Tensile and hardness tests were carried out in order to identify mechanical properties of composites. The results of microstructural study revealed uniform distribution of graphite particles and low porosity in micro composite specimens.The results of this study revealed that as graphite percentage was increased, there was significant increase in ultimate tensile strength, yield strength and ductility, accompanied by a nominal drop in the hardness of the material

Abstract: In the present work AA1100/ Al₃Ni MMC was successfully fabricated using the in-situ method of stirring and squeeze casting. The effects of amount of Ni powder on the formation and mechanical behavior of Al-Al₃Ni MMC were investigated. The fabricated MMC was characterized using XRD and optical microscope. The XRD patterns clearly indicated the presence of Al₃Ni particles without the formation of intermediate phases. The in-situ formed Al₃Ni particles were found to have uniform distribution, good bonding and clear interface. The mechanical and tribological properties such as hardness, Ultimate Tensile Strength (UTS) and dry sliding wear behavior of AA1100/ Al₃Ni MMC were compared for stir and squeeze casted MMCs with different percentage in weight of Al₃Ni (5, 10 wt. %) and it was found that properties improved with increase in Al₃Ni content and all properties of squeeze casted MMCs were superior to stir casted MMCs.

Abstract: In the field of material science and engineering, there is a great impact ever since the invention of composites materials. High strength to weight ratio provides the attractive combination that moves composite materials into new era. The conventional materials like cast iron, steel, and aluminium alloy are replaced by the composite materials due to its superficial properties and could be applied in aerospace and automotive applications. Powder metallurgy fabrication technique is one of the best and attractive methods for producing metal matrix composites because of its better distribution of particles and reliability and cost in manufacturing. In this paper, composites based on aluminium alloy (Al 2024) reinforced with 10% weight fraction of hard ceramics like Aluminium oxide (Al₂O₃) and 10% weight fraction of Aluminium oxide (Al₂O₃) with 5% graphite particles is produced by Powder metallurgy method. Hardness and wear test are conducted for the Al 2024, Al-10%Al₂O_3, and Al-10% Al₂O₃-5% Graphite. In addition the surfaces of the composite are analyzed by SEM to study the wear of the composites.

Abstract: In this work, Abrasive Water Jet Machining (AWJM) on aluminum based hybrid composite with Silicon Carbide (SiC) and Boron Carbide (B₄C) reinforcement particles are investigated. Two different abrasive grain sizes of 80 mesh and 120 mesh are selected to carry out the experiments. The cutting parameters namely pressure, standoff distance (SOD) and traverse speed are assessed in terms of the kerf angle, Material Removal Rate (MRR) and Surface Roughness (Ra). The result shows that the coarse abrasive particle has a favorable effect on the MRR, while the fine grained abrasive particle produced minimum kerf angle and good surface finish.

Abstract: Aluminium alloy(A 356) has improved properties such as tension and elongation butit is decreased in hardness property compared to ceramics and therefore silicon carbideparticle (SiCp) is added with aluminium alloy to increase its hardness. Silicon Carbideparticle is abrasive and hence having poor interfacial bonding between ceramics andaluminium, so that the surface of the ceramics is coated with Multi Wall Carbon Nano Tubes(MWCNT). In this paper 10% of SiCp is taken for the experiment and coated with 1.5%, 2%,2.5% of MWCNT and this coated SiCp mixed with molten A 356 using stir casting method.The prepared castings were mechanically tested using Universal Testing Machine (UTM),Vickers hardness Testing Machine, Impact Testing Machine and Optical Microscope andtheir mechanical properties and morphological characteristics were studied

Abstract: In this paper a literature review is made on the application of nanofluids as coolant in automobile radiators. The nanoparticles by virtue of their smaller size possess more surface area than the bulk material, which shall enable them to absorb and dissipate heat at a faster rate. Generally water and ethylene glycol are used as coolants in automobile radiators. Several investigators have used nanofluids consisting of nanosize particles of TiO₂, Al₂O₃, SiO₂, CuO, Fe₂O₃, etc., suspended in the coolant used in the radiator of automobiles. These investigators have observed that the application of nanofluids increases the cooling rate and shall pave way for reducing the weight and size of the radiator, there by contributing to smaller and efficient radiators.

Abstract: Automobile emission is considered as the major source of pollution. Two wheelers are the main contributors in that due to its large number. For controlling the pollution the available methods of are pre-pollution control and post pollution control. This work is based on the post pollution control method in two-wheeler automobiles using magnesium as a catalyst. To achieve this objective, an innovative design of catalytic converter for two-wheeler automobiles is proposed using magnesium nanoparticle as a catalyst. This proposed method aims in the prevention of environmental pollution contributed from two-wheeler automobiles. It involves the use of magnesium which is cheaper than the counter parts rhodium nanoparticles, platinum, and palladium.

Abstract: This paper presents the preparation, characterisation and thermal behavior of TiO₂/water Nanofluids with different concentration. The presence of Nanosized particles in the conventional heat transfer fluids enhances its thermo physical character. In the present work, TiO₂/water Nanofluids with various volume concentrations were prepared by dispersing a specified amount of spherical sized TiO₂ Nanoparticles in distilled water without any surfactant. To get a uniform dispersion and stable suspension, the Nanofluids were kept under ultrasonic vibration continuously for 3 hours. Zeta potential measurement brought detailed insight into the causes of dispersion, aggregation of Nanofluids. The KD2 Pro, fully portable thermal properties analyser, was used to measure thermal conductivity of nanofluids. The viscosity of the nanofluid was measured using a Brookfield Viscometer. The experimental results show that the thermal conductivity increases with an increase of particle volume fraction and the enhancement was observed to be 9.22% over the base fluid for volume concentration of 0.75%. From the experimental observations, enhancement in thermal conductivity is larger than the enhancement in viscosity.