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In the current exploration an impact of 44 µm estimated B4C support expansion on the mechanical conduct of Al2618 combination has been contemplated. The Al2618 compound metal composites with 2, 4, 6 and 8 changing weight rates of B4C were created by stircast strategy. The orchestrated 44 µm estimated B4C particles built up Al2618 combination composites were exposed to microstructural considers, mechanical properties testing. Microstructural portrayals of acquired examples were completed by SEM microscopy and EDS spectrums. The B4C particles were uniformly disseminated and existences of these particles were affirmed by the EDS patterns. The hardness and tensile qualities of metal composites have been upgraded with the expansion of B4C support. There was decline in the ductility of the Al2618 compound after the joining of the support. Different crack and failure systems were seen in the Al2618-B4C composites utilizing SEM.

The current work intended to synthesize Al-Mg-Si (Al6061)-B4C particulate metal matrix composites by varying weight percentage of B4C particulates (0, 3 and 6 wt.%) with an average particle size of 80 to 90 microns by vortex process (melt technique). The incorporated B4C particles distribution in the Al6061 alloy matrix was studied by SEM micrographs and confirmed the thorough distribution of carbide particles in the matrix. EDS spectrums and XRD patterns were obtained for Al6061 and its composites to identify various elements and phases present in the Al6061-B4C composites. Al6061 alloy with 3 and 6 wt.% of B4C composites was subjected to hardness, tensile, impact and fatigue behavior evaluation. By adding boron carbide particles hardness, tensile and impact strength of Al6061 alloy was improved with slight decrease in fatigue strength. Further, various fracture morphologies were studied on tensile, impact and fatigue fractured surfaces using SEM micrographs.

The current research work primarily focuses on synthesizing and exploring Al2014 alloy microstructure and wear behavior reinforced with 20 μm Al2O3 (alumina) particles. A novel two-stage stir casting (melt stirring) technique is adopted to produce the composites, and the weight percentage of reinforcement is maintained at 9, 12, and 15 to know the effect of varying weight percentage on microstructure and wear behavior. To achieve better dispersion, alumina particles have been introduced in two stages. X-ray diffraction (XRD) and electron microscope/energy-dispersive spectroscope (EDX) are used to characterize the prepared composites. In the Al2014 matrix, microstructural characterization showed a fairly uniform dispersion of Al2O3p. The presence of alumina is confirmed by the XRD pattern carried out on the produced composite (Al2014-15 wt.% Al2O3p). Wear properties of as-cast Al2014 alloy and composites (Al2014-Al2O3p) at 9, 12, and 15 wt.% have been studied. Dry sliding wear tests have been conducted over a load range of 9.81 N-49.05 N and sliding speed of 100–600 RPM using pin-on-disk machine. Results revealed the frictional coefficient of as-cast Al2014 alloy and produced composites increase with an increase in load up to 49.05 N. Nevertheless, the frictional coefficient of both as-cast Al2014 alloy and produced composite increase continuously by increasing the speed. The wear rate of both Al2014 matrix alloy and Al2014-Al2O3 reinforced composite increase with the increase in load and sliding speed. To know the possible wear mechanisms, worn surface and wear debris have been studied by using electron microscopy and EDS examination to specify the formation of the oxides.

In the current investigation, efforts are being made to produce an Al2014-Al2O3p composite with variable particle size of 88 mm by liquid stir casting route. 9, 12 and 15 weight proportions of Al2O3p were added to the Al2014 base alloy. By using SEM and EDS testing, microstructural studies have been conducted. Al2014-9, 12 and 15 weight proportion of Al2O3p composites mechanical behavior is determined in line with ASTM standards. Electron microscopic images showed that alumina (Al2O3p) particles are dispersed uniformly within the Al2014 composite matrix. EDS study confirmed the proximity of Al and O elements to composites reinforced by Al2O3p. It is also found that Al2014-Al2O3p composite hardness, UTS, and yield strength are improved by the addition of 9, 12 and 15 weight proportion of Al2O3p. Due to the addition of alumina particles in the Al2014 matrix alloy, the ductility of the produced composites decreases. Tensile fractography is performed using SEM to consider the mechanisms for failure.

In the present research, an effect of nanographite and zirconium oxide (ZrO2) dual reinforcement addition on the mechanical and wear behaviour of Al7075 alloy has been studied. The Al7075 alloy with constant 3 wt.% of graphite particles and varying (3 and 6) weight percentages of ZrO2 particle-reinforced hybrid composites were fabricated by stir casting method. The synthesized dual particle-reinforced Al7075 alloy hybrid composites were subjected to microstructural studies, mechanical and wear properties testing. Microstructural characterizations of obtained samples were carried out by scanning electron microscopy. The graphite and ZrO2 particles were evenly distributed in the Al7075 alloy matrix. The hardness, impact and tensile strength of hybrid composites have been increased with the addition of dual reinforcements. There was slight decrease in the ductility of the Al7075 alloy after the incorporation of these reinforcements. The wear behaviour of the prepared samples was tested at varying loads and speeds. The hybrid composites exhibited a superior wear resistance as compared to base matrix alloy Al7075. Various fracture and wear mechanisms were observed in the Al7075 alloy with graphite and ZrO2 particle-reinforced composites using SEM.

Insitu AlB2 particles with Al6061 combination system increase its hardness strength and abatement in density. Al6061-AlB2 insitu composites were created by exothermic response utilizing premixed halide salt KBF4 and Na3AlF6 (for refining aluminium matrix) by liquid strategy with distinct weight rates of AlB2 particles. The as cast matrix combination and the related insitu are exposed to heat treatment at a required temperature of 535°C for one hour followed by quenching in various media like ice, oil, and water. Then the specimens are exposed to an artificial ageing for 175°C for around 10 hours. Microstructural study was directed on as cast and insitu composite to determine the dissemination of AlB2 particles in the base matrix. The reinforced composite showed improvement in hardness when contrasted with as cast alloy. There has also been some improvement in hardness with increasing AlB2 content. The Al6061-AlB2 particulate composites showed critical improvement in hardness when quenched in ice.

The current work intended to synthesize Al6061 alloy with 5 wt% of micro Al2O3 particulate metal matrix composites using liquid metallurgy technique. Scanning electron microscopic images of the synthesized composites were obtained to demonstrate the uniform dispersion of the reinforced micro Al2O3 particles in the matrix. EDS spectrums confirmed the various elements present in the Al6061- Al2O3 composites, XRD patterns reveal the Al and Al2O3 phases in the composites. Hardness, tensile and impact tests were carried out to find out the impact of micro Al2O3 on the various mechanical properties of the composites. Synthesized composites hardness, tensile and impact strength were found to be more with the incorporation of Al2O3 particles. Further, tensile and impact failure analysis was studied using fractured surfaces SEM micrographs.

The microstructure and mechanical behavior of Al2219 metal alloy with 2, 4, 6, 8 and 10 wt% of B4C composites were studied. The composites comprising 2 to 10 wt% of B4C in Al2219 alloy were amalgamated by liquid metallurgy process. The prepared composites were subjected to the microstructural studies using SEM. Further, the mechanical behavior of Al2219 with B4C composites were tested as per ASTM methods. The SEM characterization identified thorough dispersal of particles in the base alloy. Further, mechanical behavior of Al2219 alloy has been improved with the addition of B4C particles. The enhanced hardness and tensile strengths were obtained in the composites. The ductility and density of the Al2219 alloy was reduced after the inclusion of boron carbide particles.

In the present work, an attempt has been made to study the mechanical behavior and tensile fractography of 40- and 90-micron-sized boron carbide (B4C) particulate-reinforced light metal (LM) 29 alloy composites. LM29 alloy with 3, 6 and 9 wt. % of 40- and 90-micron-sized B4C composites was synthesized by liquid stir method. Microstructural analyses were obtained by using scanning electron micrographs and energy-dispersive spectrographs. Mechanical properties like hardness, ultimate, yield strength and ductility were evaluated as per American Society for Testing and Materials standards. Scanning electron microscope micrographs show the even dispersal of B4C particulates in the LM29 alloy, and this is confirmed by energy-dispersive spectroscopy analysis. Further, hardness, ultimate and yield strength of matrix LM29 alloy were enriched with the addition of B4C reinforcement and were more in the case of 40-micron-sized reinforced composites. There was small decrease in ductility of composites in both cases.

In the present examination, the mechanical properties of Al2218-nano B4C composites displayed. The composites containing 4 to 8 wt. % of nano boron carbide in ventures of 4 wt.% were readied utilizing liquid metallurgy method through stir casting. For every composite, fortification particles were preheated to a temperature of 400˚C and afterward added in ventures of two into the vortex of liquid Al2218 compound to improve the wettability and dispersion. Microstructural examination was carried out by SEM and elemental investigation was finished by EDS. XRD Analysis used to recognize the B4C phases in the Al grid. Density, tensile, compression and hardness tests were done to distinguish various properties of composites. The aftereffects of this investigation uncovered that as the weight % level of nano B4C particles were expanded, there was noteworthy increment in hardness, UTS, yield and compression strength of Al2218 amalgam composites. Further, there was slight drop in the density and malleability of the Al2218 amalgam composites when contrasted with the base. Tensile fractured surfaces analysis was conducted by using SEM.

In the present investigation, preheated K2TiF6 flux were blended with B4C particle (an average size of 33 µm) at 0.2 ratios and were incorporated into molten Al at 750 °C through conventional stir casting. Microstructural studies of as cast 6xxx alloy and composite were done using SEM/EDS/XRD. A fairly uniform distribution of B4C particles were observed throughout the matrix with few agglomeration at certain places. Ultimate tensile strength and wear behaviour of the prepared composite were tested using computer assisted UTM and Pin-On-Disk apparatus under elevated temperature (100 °C and 200 °C) respectively. The results shows that strength of composite decreases under the influence of temperature at all testing parameters. It is believed that material had undergone severe plastic deformation before the initiation of necking and mild brittle to severe ductile transition has occurred leading to catastrophic failure at high temperature and is evident from the fractography studies. The formation of tribo-coat or layer at the Pin sample and steel disc interface restricted the direct contact with each other. Further, the addition level of test temperature and developed frictional heat encourages Al atoms to diffuse faster at the slip plane resulting in severe wear from the material surface. Small narrow abrasive lines, particle de-bonding, softened tribolayer along with few wear debris adhered to worn surface (due to micro ploughing and oxidation) were observed on the surface of composite at all conditions under 200 °C test temperatures. Presence of “O” and “Fe” peak in the EDS pattern (on worn surface) confirms the existence of oxidation layer and micro ploughing on steel disc at higher test temperature.

Al2O3 may be the most important reinforcement in aluminum-based composites that are rising quickly in modern years. The significance of this paper is to study the influence of Al2O3p size variation (i.e. 53 µm and 88 µm) and content (i.e. 9, 12, and 15Wt %) on density, hardness, tensile strength, elongation to fracture and wear studies. During the preparation of each composite, the ceramic reinforcements were introduced in a novel way which involves two-stage additions of reinforcements during liquid stirring. It has been found that because the size of the Al2O3p is reduced, measurement of the density showed that 2014Al-Al2O3p composites contained slight porosity and also the quantity of porosity among the prepared composites higher with diminishing the Al2O3p size and increasing weight percentage of Al2O3p. In addition to this, the results show that by decreasing the Al2O3p size and increasing the weight proportion of the Al2O3p the tensile strength and hardness of the prepared composites increase. Microstructural characterization carried out for the 2014Al-Al2O3 composites using scanning electron microscopy (SEM) which showed a fairly homogeneous distribution of Al2O3p with grain refinement of the matrix. Wear test is conducted for the prepared composites by utilizing a computerized pin on disc wear testing machine which shows greater wear resistance property as the size of the Al2O3p reduced.

In the present work, an attempt is made to synthesize cermet (WC-Co) reinforced Al7075 metal matrix composite by liquid metallurgy route. The dry sliding wear behavior of these prepared composites was studied with varying sliding speed, load and sliding distance. Cermet in an amount of 6 wt% is used as reinforcement in Al7075 matrix. Microstructural characterization of the prepared composites is carried out using SEM/EDX and XRD studies. X-ray diffraction studies have revealed the peaks corresponding to α-Al, WC, Co and minor Al5W phases. SEM/EDX characterization revealed the uniform distribution of cermets in Al matrix. Dry sliding wear characteristics of the prepared composites were studied using a pin-on-disc testing machine. The wear rate for alloy and composites decreased with increase in sliding speed and increased with increase in applied load and increasing sliding displacement. The worn surfaces of the composites were investigated using optical microscope.

MMC based on aluminium (Al) were produced for light-weight applications especially in aviation and automobile areas. Present paper deals with the fabrication and mechanical performance of AA6061 matrix composites fortified with Al2O3 (alumina) and graphene particulates. Fluid metallurgy method namely stir casting route was employed for fabricating the hybrid composites. Al2O3p and graphene powder are mixed in different weight fractions in which graphene (1 wt. %) particle reinforcement is held consistent and Al2O3 reinforcement is differed freely with 5, 10 and 15 wt. %. Using optical analyser and SEM equipment, microstructural examination is carried out and the result reveals that the graphene and Al2O3 particles prevalently are homogeneously appropriated on the grain limits of Al matrix and Al2O3 particles are disseminated between graphene in the as-cast AA6061 MMC’s. Detailed analysis on investigation of the microstructure and mechanical aspects of Al6061-graphene-Al2O3p composites is presented by following ASTM guidelines, results uncovered that with increment in reinforcement particles, there is an enhancement in the hardness, ultimate strength, yield strength and a decline in the elongation values was however noticed when contrasted with Al6061 alloy. Fractography investigation revealed dimples in unreinforced alloy and the composite.

Aluminium matrix composites (AMC’s) focus primarily on improved specific strength, high temperature and wear resistance application. Aluminium matrix reinforced with ceramic particulates has good potential. With high strength and sensible wear resistance properties AMCs found their applications within the field of automobile components, defence materials, die and gear materials, etc. In the present work, the hard ceramic particulates of tungsten carbine (WC) and soft ductile particulates of cobalt (Co) mixtures are used as reinforcements (at 6 and 9 wt%) in CERMET form with a particle size range from 10 to 15 µm. The processing of composite is done by the stir casting method. Optimized processing temperature technique is adapted in processing of composite. The presence of the homogeneously distributed particulates is observed through scanning electron microscope (SEM). XRD analysis also reveals the presence of reinforcement particulates and other phases. Dry sliding wear behaviour of Al−WC–Co composite samples was analysed with the help of a pin on disc wear and friction monitor. The present analysis reveals the improved wear resistance of composite over the base alloy. Synthesized composites exhibit superior wear resistance property over the base alloy. Worn surface morphology was studied with the help of SEM in order to observe the wear behaviour of the samples.

In the present research, the effect of 44-μm-sized B4C addition on the mechanical and wear performance of Al2024 alloy has been studied. The Al2024 alloy metal matrix composites reinforced with varying wt% (2, 4, 6 and 8) of B4C particulates were fabricated by stir cast route. The synthesized composites were subjected to microstructural studies, mechanical and wear properties testing. Microstructural characterizations of obtained samples were carried out by SEM microscopy and XRD patterns. The presence of B4C particles was confirmed by the XRD patterns. The hardness, tensile and compression strengths of metal composites have been enhanced with the addition of B4C reinforcement. There was, however, a decrease in the ductility of the Al2024 alloy composite after the incorporation of the reinforcement. The wear behaviour of the prepared samples was tested at varying loads and speeds. The microcomposites exhibited superior wear resistance. Various fracture and wear mechanisms were observed in the Al2024–B4C composites using SEM.

Present paper highlights on the development of 5 wt% in situ AlB2 particle reinforced composites produced by mixed salt exothermic chemical reaction method at 850 °C in molten aluminum Al6061 using liquid metallurgy route. The study reveals the impact of AlB2 particles by varying reaction holding time (RHT) from 15 to 60 min in steps of 15 min at a fixed reaction temperature of 850 °C. The impact of reaction holding time on the microstructure of AlB2 particle morphology was explored. Results revealed uniform scattering of AlB2 particles in the matrix with different morphology like cylindrical, hexagonal and spherical shapes and varied with respect to holding time. Mechanical properties like yield strength, ultimate tensile strength, compression strength and hardness enhanced with 5 wt% of AlB2 reinforcement with respect to reaction holding time; however, it was observed that ductility of the in situ composite reduced with increasing reaction holding times.

In the existing exploration, an effort is being made to synthesize Al2O3p ceramic-reinforced 2014Al matrix composites by liquid stirring (Stir Casting) in order to contemplate the effect of Al2O3p on mechanical and wear properties of the prepared composites. The Al2O3p ceramic additional level is maintained at 9, 12 and 15 wt%. An innovative method of adding 2-stage reinforcements during liquid stirring is used throughout the course of preparation of each composite. An average particle size of 53 μm Al2O3p is used. By using scanning electron microscopy (SEM), microstructural characterization is performed for the above synthesized composites, which showed moderately uniform Al2O3p distribution with matrix grain refinement accompanied by X-Ray Diffraction (XRD) analysis. The hardness of the resultant composites is examined using Zwick micro hardness tester and the above synthesized composites are examined mechanically as per ASTM standards by means of computerized universal testing machine. With increment in wt% of Al2O3p, improvements in the value of hardness and tensile strength of the synthesized composites were seen. Percentage improvements of 28.88% (9 wt%), 43.36% (12 wt%) and 68.54% (15 wt%) in terms of hardness and 5.09% (9 wt%), 17.62% (12 wt%) and 29.03% (15 wt%) in terms of tensile strength were obtained ,respectively. The sliding wear test is carried out by using a computerized pin on a disc wear tester with counter surface as an EN31 steel disc (HRC60) and composite pin as specimens. The synthesized composites revealed the superior wear resistance property. Worn surfaces were studied with the help of SEM in order to know the wear mechanism. Overall investigation outcomes are very interesting and motivate to carry out further research work.

Ceramic B4C particulates with an average particle size of 33 µm were reinforced with 6061Al matrix by novel two step melt stirring at 750°C. In experimentation, an addition level of 7Wt% B4Cp and K2TiF6 flux is ball milled to achieve 0.15 ratios for 2hours. The B4C particulate composites were characterized and tested for hardness and wear properties evaluation. Scanning Electron Microscopy (SEM) micrographs have fairly dispersed ceramic B4C particulates with in ductile Al matrix attributed to two-step process and K2TiF6 flux. Dry sliding wear behavior of prepared ceramic composite were measured by Pin-on-disc wear evaluating apparatus at 200°C test temperature under atmospheric humidity condition. Results showed that pull-out of B4Cp, formation of tribo-film and oxidation of Al protects the direct contact of composite pin at interface under room temperature condition whereas at elevated temperature, composite pin suffer severe plastic deformation due to temperature assisted diffusion of Al atoms; thereby decreasing the wear performance of ceramic composite at all loads. /Energy Dispersive X-ray Spectrometry (EDS) were used to identify the type of wear mechanisms and to understand the surface morphology.Ceramic B4C particulates with an average particle size of 33 µm were reinforced with 6061Al matrix by novel two step melt stirring at 750°C. In experimentation, an addition level of 7Wt% B4Cp and K2TiF6 flux is ball milled to achieve 0.15 ratios for 2hours. The B4C particulate composites were characterized and tested for hardness and wear properties evaluation. Scanning Electron Microscopy (SEM) micrographs have fairly dispersed ceramic B4C particulates with in ductile Al matrix attributed to two-step process and K2TiF6 flux. Dry sliding wear behavior of prepared ceramic composite were measured by Pin-on-disc wear evaluating apparatus at 200°C test temperature under atmospheric humidity condition. Results showed that pull-out of B4Cp, formation of tribo-film and oxidation of Al protects the direct contact of composite pin at interface under room temperature condition whereas at elevated temperature, composite pin suffer severe plastic deformation due to temperature assisted diffusion of Al atoms; thereby ...

In the current research work synthesis, characterization, mechanical and wear behavior of 2, 4 and 6 wt% of nano-ZrO2 particulate-reinforced AA2014 alloy composites have been investigated. The matrix phase of AA2014 alloy containing nano-ZrO2 particulates composites was geared up by two-stage melt stir system. After the preparation, the organized composites were studied by SEM and EDS for analyzing the microstructures and chemical elements. Further, mechanical characterization and wear studies of as-cast AA2014 alloy and AA2014-nano-ZrO2 composites were studied. From the investigation, it was observed that the tensile behavior of composites was enhanced due to addition of nano-sized ZrO2 particles in the AA2014 alloy matrix. In nano-ZrO2-reinforced composites, the percentage elongation decreased. Further, the wear loss increased with respect to the load for all the prepared materials. To study the fractography and different wear mechanisms for various test conditions of different compositions, tensile fractured surfaces and the worn surfaces were observed by SEM.

The present work deals with the preparation of the aluminium matrix composite using a ceramic and metallic combination as reinforcements and using liquid metallurgy route of solidification process. The desired properties of composites have been influenced by the solidification behaviour of the cast metal matrix composites, which has been imposed to study the solidification behaviour of metal matrix at different weight fraction of reinforcement particulates. Al7075 was used as matrix and tungsten carbide, and cobalt particulates were used as reinforcements. During the preparation, an addition of magnesium was used to increase the wettability of the particulates during the mixing. XRD/EDX/SEM characterizations of the prepared composites were conducted, where a fairly uniform distribution of the reinforced particulates was found over the matrix.

Al2618 alloy composites containing 6 wt% nano B4C were prepared by liquid metallurgy two stage stir casting process. Characterization was performed using scanning electron microscope to validate the homogenous distribution of nano B4C particles in the Al2618 alloy matrix. The presence of B and C elements was confirmed by EDS analysis in the nano B4C reinforced metal composites. The mechanical behavior of the prepared nano composites were evaluated as per the ASTM standards, and it was noted that the tensile strength (ultimate strength and yield strength) and compression strength increased with the addition of 6 wt% nano B4C particles. Finally, to understand the failure mechanisms the fractography analysis was conducted on the broken tensile specimens by using SEM images.

Metal matrix composites (MMC’s) form appropriate choice of materials where there is a demand for stiffness, strength combined with low weight for different applications. The applications of Aluminum based MMC’s as engineering materials has been exceedingly increased in almost all industrial sectors. Aluminum strengthened with Al2O3p gives excellent physical and mechanical properties like high hardness, low density, high electrical conductivity etc., which are generally used in the field of aerospace, automobile and industrial applications. In present work, an attempt is being made to integrate 2014 Al alloy with Al2O3p by two stage stir casting with addition level of reinforcement maintained at 9 and 12 wt%. Microstructural characterization carried out using scanning electron microscopy showed fairly uniform distribution of Al2O3p with grain refinement of the matrix. These prepared composites are mechanically characterized as per the ASTM standards using computerized universal testing machine. Improvements in tensile strength, density and hardness of the prepared composites were observed with increase in the reinforcement wt%. Percentage improvements of 5.09% (9 wt%), 17.65% (12 wt%) in terms of tensile strength and 29.18% (9 wt%), 43.69% (12 wt%) in terms of hardness were obtained respectively.

Metal matrix composites have large application in various fields like aerospace and automobile applications due to higher strength to weight ratio owing to their excellent combination properties. Considering this fact, the present work is taken up with objective of evaluating tensile and compressive behavior of 6061Al-B4C composite at room temperature. The composite is prepared via melt stirring method with 9wt% of boron carbide particulates of size 8 microns at processing temperature of 750°C. Microstructural studies of prepared composites were carried out using SEM analysis. Hardness measurements of the composite were carried out using micro-Vickers hardness tester with a load of 250gm and dwell time of 30sec. Tensile and compressive behaviors were studied using universal testing machine at room temperature condition. Microstructural studies revealed fairly uniform distribution of B4C particles in 6061Al matrix. Al-B4C composite has exhibited better tensile and compressive strength in comparison with matrix alone, which increases its durability and load carrying capacity. Therefore, 6061Al-B4C system could be used as replacement of steel and other ferrous materials in structural applications.

In the present work, 6061Al matrix reinforced with 9wt. % B4C particle size of 88 microns is produced by liquid metallurgy method. During processing, K2TiF6 and B4C in the ratios of 0.2 were preheated and added to Al melt at 750°C with continuous stirring to obtain uniform distribution of B4C in 6061Al matrix. The casted composites were subjected T4 and T6 type heat treatments with quenching medium as water at room temperature. Microstructure characterization was done for both the heat treated and un-heat treated specimens using optical microscope/XRD. The presence of Mg2Si was confirmed through XRD studies. High temperature wear tests were conducted using Pin-On-Disc apparatus. Wear test samples were prepared as per ASTM G99 standards and slide against stainless steel disc (32HRC) with constant sliding velocity of 2.51m/sand constant sliding distance of 1000m by varying the load ranging from 9.81N to 39.24N at test temperatures of 150°C. Results of wear tests suggest that wear resistance increases in the order of matrix, composite without aging and composite with aging. The worn surface morphology showed that heat treated Al-B4C composites have more wear resistance capacity than as cast 6061Al.

The present work deals with micro-structural and wears behavior of Al-AlB2 insitu composite. These composites containing 3 and 5wt% of insitu AlB2 particles were produced by exothermic dispersion (insitu) involving reaction between Al6061 and KBF4 halide salt. Micro-structural characterizations were conducted using SEM/EDX which revealed uniformly distributed AlB2 particulates in the Al6061 base matrix. The machine used to test and evaluate wear properties of the prepared composite specimens is pin on disc type, disc made up of EN32 steel was used as counter face and loads 29.43N, 39.24N and 49.05N and 100, 200 and 300 rpm were employed. The results revealed about wear details in terms of volumetric loss which is proportional to sliding speed and normal load applied for all the conditions

This work investigated the influence of silicon carbide and graphite on the microstructure and mechanical behavior of Al6061-SiC and Al6061-Graphite composites. The investigation reveals the effectiveness of integration of SiC and Graphite in the Al6061 alloy for studying mechanical properties. The composites were fabricated using liquid metallurgy route. The Al6061-SiC and Al6061-Graphite composites were fabricated separately by introducing 9 wt. % of SiC and graphite particulates. The characterization was performed through Scanning Electron Microscope and Energy Dispersive Spectrum. The particle distribution was uniform in these composites. The grains were refined by inclusion of SiC and Graphite particulates. The density, hardness, ultimate tensile strength, yield strength and percentage elongation of both SiC and Graphite composites were evaluated. Further, a comparative study has been made between the Al6061-SiC and Al6061-Graphite composites. The SiC and graphite addition in the Al matrix proved to account for the dramatic change of the fracture mechanism of the composites

This work investigated the influence of Al 2 O 3 and graphite on the microstructure and mechanical behavior of Al6061- Al 2 O 3 and Al6061-Graphite composites. The investigation reveals the effectiveness of incorporation of Al 2 O 3 and Graphite in the Al6061 alloy for studying mechanical properties. The composites were fabricated using liquid metallurgy route. The Al6061- Al 2 O 3 and Al6061-Graphite composites were fabricated separately by introducing 9 wt. % of Al 2 O 3 and graphite particulates by two stage melt stirring process. In this reinforcement particulates were added in two steps to increase the wettability. The characterization was performed through Scanning Electron Microscope and Energy Dispersive Spectrum. The particle distribution was uniform in these composites. The grains were refined by addition of Al 2 O 3 and Graphite particulates. The density, hardness, ultimate tensile strength, yield strength and percentage elongation of both Al 2 O 3 and Graphite composites were evaluated as per ASTM standards. Further, a comparative study has been made between the Al6061- Al 2 O 3 and Al6061-Graphite composites.

In the present investigation, effect of applied normal load and sliding speed on wear behaviour of 2, 4 and 6 weight percentages of TiC particulate reinforced Al2219 alloy composites were reported. Al2219 - Titanium Carbide composites were fabricated by conventional liquid stir casting method. The microstructure of the composites was examined by scanning electron microscopy. The wear resistance of metal matrix composites was studied by conducting dry sliding wear assessment using a pin on disc apparatus. The experiments were conducted at a constant sliding speed of 700rpm and sliding distance of 2000m over varying loads of 0.5kg, 1kg, 1.5kg and 2kg. Similarly experiments were conducted at a constant load of 1.5kg and sliding distance of 2000m over varying sliding speeds of 600, 700, 800 and 900rpm. The results showed that the wear resistance of Al2219-TiC composites was better than the unreinforced alloy. The wear rate was found to increase with the applied load and sliding speed. Study of wear worn surfaces was carried out using scanning electron microscope.

In the present investigation, microstructure study and tensile behavior of B4C particulate reinforced Al2024 alloy composites have been reported. Al2024 matrix composites containing boron carbide were fabricated by conventional stir casting method. The composites containing 3 and 6 wt. % of B4C (80 micron size)particulates were fabricated for the study. The micro- structure of the composite was examined by optical microscopy. Images were taken to identify the presence of B4C particle in aluminum matrix. Further, tensile behavior of as cast Al2024 alloy and Al2024-3 wt. % B4C and 6 wt. % B4C composites were studied. Tensile properties like ultimate tensile strength, yield strength and percentage elongation were evaluated as per ASTM standards. Microstructural observation revealed the uniform distribution of particles in the Al2024 alloy matrix. It was found from the analysis, that the ultimate tensile strength of composite was increased due to increasing amount of boron carbide particle in the composite and the yield strength was increased due to the higher value of boron carbide. Also percentage elongation of the composites decreases with increase of the order of boron carbide. Finally, it was found that in the stress - strain curve, the boron carbide was the main factor in improving the tensile strength of composites because of its high hardness. The composites in the present study have great potential for application as structural materials.

In the present work an attempt is made to synthesize 6061Al – Cu coated Al 2 O 3 particulate metal matrix composite by two stage melt stirring method. 6061Al alloy is reinforced with copper coated Al 2 O 3 particulate through compo casting technique. Compo casting technique is adopted over single stage melting stirring process as this eliminates wettability problem of particulates and results in better properties of MMC. The MMC is obtained by incorporating 3, 6 and 9 wt.% of un-coated Al 2 O 3 and Cu-coated Al 2 O 3 with 6061Al alloy. Microstructural analysis reveals that Cu coatings around Al 2 O 3 particulates have improved the wettability at the interface resulting in better incubation and avoiding segregation of particulates in the melt which are evident from SEM microphotographs. Mechanical properties like density, hardness and tensile strength were studied for both copper coated and uncoated Al 2 O 3 reinforced composite at room temperature. Significant increase in mechanical properties was observed for copper coated Al- Al 2 O 3 composite due to improved wettability and uniform distribution of particulates within 6061Al matrix compared with Al- Al 2 O 3 composite without Cu coatings.

In the present investigation synthesis, microstructure, mechanical and wear behavior of 5 weight percentage of nano Al2O3 particulate reinforced AA7475 alloy composites has been reported. AA7475 matrix composite containing nano Al2O3 were fabricated by conventional stir casting method. The microstructures of the composites were examined by scanning electron microscopy. Further, mechanical and wear behavior of as cast AA7475 alloy and AA7475 - 5 wt. % nano Al2O3 composites were studied. Mechanical properties like hardness, ultimate, yield strength and percentage elongation were evaluated as per ASTM standards. Pin on disc apparatus was used to conduct the dry sliding wear tests. The experiments were conducted by varying loads and constant sliding speed of 300rpm for sliding distance of 4000m. Microstructural observation revealed the uniform distribution of particles in the AA7475 alloy matrix. From the analysis, it was found that the hardness, ultimate tensile strength and yield strength of composites were increased due to addition of nano Al2O3 particle in the AA7475 alloy matrix. Percentage elongation of the composite decreased in 5 wt. % nano Al2O3 reinforced composites. Further, the volumetric wear loss was found to increase with the load and sliding distance for all materials. Worn surface analysis made by using scanning electron micrographs to know the various mechanisms involved in the wear process.

Nano particulates fortified metal lattice composites are finding extensive variety of utilizations in car and sports hardware fabricating businesses. In the present investigation, an endeavor has been made to create copper-zinc-nano ZrO2 particulates strengthened composites by utilizing fluid liquefy technique. 4, 8 and 12 wt. % of nano ZrO2 particulates were added to the Cu-Zn base grid. Microstructural studies were finished by utilizing SEM and EDS examination. Mechanical behavior of Cu-Zn-4, 8, 12 wt. % of nano ZrO2 composites were assessed according to ASTM benchmarks. Checking electron micrographs uncovered the uniform dispersion of nano ZrO2 particulates in the copper zinc composite network. EDS examination affirmed the nearness of Zr and O components in nano ZrO2 strengthened composites. Further, it was noticed that hardness, UTS, yield quality of Cu-Zn composite expanded with the expansion of 4, 8 and 12 wt. % of nano ZrO2 particulates. Ductility of nano composites was decreased by adding zirconium oxide particulates. Fractography of tensile specimens were carried out by using SEM micrographs to understand the failure mechanisms. &nbsp

In this research, work is carried out on Al6082 alloy because of its thermal stability and stiffness which can be used for strong structural application, here the hard ceramic particle of Si3N4 are reinforced with Al6082 for further enhancing its strength, stiffness. Stir casting technique is used to fabricate aluminum metal matrix composition with varying wt. % of Si3N4, this technique involves cost effective process and also results in homogenous mixture between the matrix and the reinforcement. The percentage of reinforcement varies from 0 and 9wt%. When subjected to severe plastic deformation it tends to change the grain size from micron to submicron level size in the grain structure by the application of load. The scanning electron microscope reveals the distribution of Si3N4 on the surface of the sample. The hardness value increased as compared to as-cast Al6082 alloy.

The present work dry sliding wear behaviour of Al7075 alloy matrix composite reinforced with 9Wt. % of WC-Co particulates is examined after prepared by stir casting. The dry sliding wear behaviour was studied for the composites with parameters of varying sliding speed, load and sliding distance. Microstructure characterization is done using SEM/EDX studies for the composite samples. From microstructural characterization even distribution of WC-Co particulates is observed in Al7075 matrix. DUCOM wear testing machine with EN32 steel disc is used to evaluate the wear rate of the composite. Worn out surface of the composite is subjected to SEM analysis to observe the layer formations. From the results of wear studies it is observed that the composite wear rate is reduced by restricting dislocation between the matrix and reinforcement interface.

In this study, 2014 Al matrix alloy reinforced with a 9 wt% of alumina (20 μm) particulates composites by novel two stage melt stirring (stir casting) practice used to synthesize, describe and analyze wear behaviour. Adding up of reinforcement was kept at 0 and 9wt%. For each wt. % preheated (i.e., 250°C) alumina particles were introduced in to the molten 2014Al alloy in steps of two by creating a vortex to overcome the clustering effects. Produced composite was examined by SEM analysis in support of exploring the microstructures and chemical components. Additionally characterization of wear studies of cast 2014Al matrix alloy and 2014Al-Al2O3 particulate composites were analyzed. After the assessment, it had been seen that there is an improvement in the hardness of the composites prepared and this is due to the incorporation of Al2O3 particulates in 2014Al alloy matrix meanwhile. Additionally, the wear rate of all composites prepared diminishes with increase in sliding distance while the wear rate of the composites prepared enhances with increase in load. By using Scanning Electron Microscope (SEM) the diverse wear mechanism for different test states of various compositions were examined.

In this paper an effort has made to develop and characterize Al7075 alloy reinforced with Tungsten carbide (WC) & Cobalt (Co). For uniform grain size and homogeneity of the reinforcements with matrix, Cermets (WC-Co) of grain size 50 microns were prepared with the help of ball milling operation. An experiment was conducted to evaluate the microstructure; mechanical properties like hardness test & tensile test as per the standards for different weight percentages of Cermets like 3, 6 and 9wt. %. Micrographs were studied to know the micro structure of the composite material and the result showed the, randomly dispersed reinforcement particles & fine interdendritic precipitates were seen. A comparative study was conducted for the microstructure and mechanical properties by using Cermets with varied weight percentages reinforced with Al7075 matrix. Mechanical properties results reveal that there is a considerable improvement in tensile strength and hardness as the percentage of Cermet increased from 3 to 9wt. %.

Three types of bismaleimide–carbon nanotubes (CNTs) nanocomposites were fabricated using two types of original multiwalled CNTs with different diameters and one amide functionalized CNTs. The influence of diameter, content and functionalization of CNTs on the flexural and dry sliding wear behaviour were measured with universal testing machine and pin-on-disc wear apparatus. The experimental results indicated that at 1.5 wt-%, the bismaleimide-functionalized MWCNTs exhibited highest flexural strength of 156 MPa which is increased by 164% as compared to the neat matrix, and lowest specific wear rate of 1.8 × 10−4 mm3 N−1 m−1 which is decreased by 90% as compared to the neat matrix. This was attributed to the dispersion of CNTs in the matrix and the filler-matrix adhesion and internal strength of the composite.

An attempt has been made to evaluate the mechanical behaviour and wear properties of Al6061-9 wt% B4Cp composite prepared by stir casting. During the preparation of composites, K2TiF6 salt is used as flux to increase wettability of B4Cp at low temperature and also two step introduction of the mixture containing B4Cp and K2TiF6 flux (ratio of 0.3) is adopted to achieve better dispersion. Characterization of the prepared composites is done using XRD/SEM/EDS studies. Microstructural characterization has revealed fairly uniform dispersion of B4Cp in Al6061 matrix with clustering at few places. X-ray diffraction pattern taken on the prepared composite clearly reveals the presence of α-Al, B4C, Ti compound layer (Al3Ti/TiB2), AlB2 and Al3BC. Mechanical properties of the prepared composites such as hardness, UTS and specific strength have been improved by 115.3%, 38.8% and 42.8% respectively in comparison with matrix alone. Further, fractography studies conducted on the tensile specimens revealed both du...

Aluminium matrix composites are of great interest for researchers in recent years because of their excellent combinations of engineering properties over traditional materials. The machinability of these aluminium matrix composites has become vital for manufacturing industries. During machining of aluminium matrix composites, the cutting forces and surface roughness are dependent on machining parameters (feed rate, cutting speed and depth of cut) and manufacturing parameters (size of the particles, volume fraction, porosity, hardness). With this backdrop, the present work is aimed at investigating the effect of machining parameters, viz. cutting speed, feed rate and depth of cut on the cutting force components, namely, feed force (Ff), radial force (Fd), cutting force (Fc) and surface roughness. The experiments were performed on 0, 5, 7 and 9 wt% B4C particulate of 88 µm size reinforced composite specimens. The prepared specimens were subjected to turning operation on a conventional lathe machine u...

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

The epoxy nanocomposites reinforced with nano-size zirconia and alumina (0.5, 1, 5 and 10 wt%) were prepared by high shear mixing and casting method. The nanocomposites with 0.5 wt% Al2O3 nanoparticles exhibited maximum improvement in flexural strength (+156%) as well as modulus (+90%) with respect to neat epoxy. The lowest specific wear rate of 0.1 × 10−4 mm3/N/m (−95%) has been achieved with 0.5 wt% ZrO2 composite relative to neat epoxy’s value 2 × 10−4 mm3/N/m. It was observed that increment in tensile strength and moduli were more for alumina filled composites than the corresponding zirconia filled composites.

In the present investigation sysnthesis, microstructure study and tensile behavior of 3 and 9 weight percentage of B4C particulate reinforced Al7025 alloy composites has been reported. Al7025 matrix composite containing boron carbide were fabricated by conventional liquid stir casting method. The composites containing 3 and 9 wt. % of B4C particulates were fabricated for the study. The microstructure of the composites were examined by scanning electron microscopy. Further, tensile behavior of as cast Al7025 alloy, Al7025-3 wt. % B4C and 9 wt. % B4C composites were studied. Tensile properties like ultimate tensile strength, yield strength and percentage elongation were evaluated as per ASTM standards. Microstructural observation revealed the uniform distribution of particles in the Al7025 alloy matrix. From the analysis, it was found that the ultimate tensile strength and yield strength of composites were increased due to increasing amount of boron carbide particle in the Al7025 alloy matrix. Percentage elongation of the composite decreases with increasing order of B4C particulates in soft Al alloy.In the present investigation sysnthesis, microstructure study and tensile behavior of 3 and 9 weight percentage of B4C particulate reinforced Al7025 alloy composites has been reported. Al7025 matrix composite containing boron carbide were fabricated by conventional liquid stir casting method. The composites containing 3 and 9 wt. % of B4C particulates were fabricated for the study. The microstructure of the composites were examined by scanning electron microscopy. Further, tensile behavior of as cast Al7025 alloy, Al7025-3 wt. % B4C and 9 wt. % B4C composites were studied. Tensile properties like ultimate tensile strength, yield strength and percentage elongation were evaluated as per ASTM standards. Microstructural observation revealed the uniform distribution of particles in the Al7025 alloy matrix. From the analysis, it was found that the ultimate tensile strength and yield strength of composites were increased due to increasing amount of boron carbide particle in the Al7025 alloy matrix. Percentage el...

In the present work systematic study has been conducted to investigate the matrix properties by introducing nanosize Al2O3 (particle size 100 nm, 0.5–10 wt %) fillers into an epoxy resin. High shear mixing process was employed to disperse the particles into the resin. The experimental results indicated that frictional coefficient and wear rate of epoxy can be reduced at rather low concentration of nanoAl2O3. The lowest specific wear rate 0.7 x 10-4 mm3/Nm is observed for the composites with 1 wt.% which is decreased by 65% as compared to unfilled epoxy. The reinforcement of Al2O3 particles leads to improved mechanical properties of the epoxy composites. The results have been supplemented with scanning electron micrographs to help understand the possible wear mechanisms.

In the current investigation an attempt has been made and to produce ceramic Al2O3particulate reinforced 6061Al matrix composites by liquid metallurgy route (stir casting technique) and to study the dry sliding wear properties of the prepared composites. The amount of ceramic Al2O3particulate reinforcement addition was maintained at 9 and 12wt%. During the preparation of each composite the ceramic reinforcements were introduced in a novel way which involves three stage additions of reinforcements during melt stirring. The wear tests were conducted using pin on disc wear testing machine on 6061Al matrix before and after addition of Al2O3reinforcements Wear test results demonstrated the superior wear resistance of the composites over monolithic 6061Al alloy matrix. Key Words: MMC’s, Al2O3particulates, 6061Al, stir-casting

In this present work, an attempt has been made to optimize the wear properties of Al6061- SiC particulate composites. The composites containing 6 to 9 wt% of Silicon Carbide 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 300˚C and then dispersed in steps of two into the vortex of molten Al6061 alloy to improve the wettability and distribution. Dry sliding wear test method was used to conduct the experiments by using Ducom made pin-on-disc wear testing machine. Twenty seven experiments were carried out with the help of Taguchi L27 Orthogonal array. The influence of applied load, sliding speed and sliding distance on volumetric wear loss was estimated. Smaller the better parameter was chosen to optimize the wear process of prepared composites. Results show that applied load has the highest influence followed by speed and sliding distance.

The present work aims at producing 6061Al metal matrix composites reinforced with 5 and 7wt% of B4C particulates at temperature of 750°C via melt stirring method involving two-step additions. In order to improve wettability and to avoid agglomeration of B4C particulates, K2TiF6 halide salt in the ratio of 0.2 were mixed with B4C particulates and the mixture were being dropped into the melt batch wise (twice). The prepared composites were characterized by scanning electron microscopy (SEM)/energy dispersive X-ray analysis (EDX) and X-ray diffraction (XRD) studies. SEM microphotographs revealed homogeneous dispersion of B4C particulates without agglomeration in 6061Al matrix. Indexing of the XRD peaks confirmed the presence ofα-Al, B4C and minor phases like Al3Ti and Al3BC. Presence of Al3Ti phase as confirmed by XRD and EDX studies is clear indication of Ti compound/layer formed around the B4C particles. Further, improvements in mechanical properties like hardness, tensile and compression strengths of the ...