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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 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.

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.

Current work aims at producing Al–4B grain refiners indigenously having different microstructures under different processing conditions by the effect between liquid Al and KBF4 halide salt. Production temperatures of 800, 900 and 1000 °C and times of 45, 60 and 75 min were selected for processing of Al–4B refiners. These prepared refiners were subjected to microstructural studies by XRD and SEM/EDX. Characterization studies suggest that temperature of 800 °C has revealed the hexagonal morphologies of aluminium boride intermetallic particles with wide size ranges and more uniform distribution which are confirmed by the EDX analysis. However, other reaction temperatures (900 °C and 1000 °C) have resulted in formation of elongated and agglomerated morphologies of aluminium boride intermetallic particles. Aluminium borides present in various Al–4B refiners enhance in size with enhancement in processing time (from 45 to 75 min) and processing temperature (from 800 to 1000 °C). Among all the reaction temperatures and times studied, high volumes of the aluminium borides (smaller than 10 μm) were observed at 800 °C-60 min Further, by adding fixed amount of 0.01%B prepared master alloys were tested for refining performance on Al–7Si alloy. Results of grain refinement suggest that addition of 0.01% of B using Al–4B refiners produced at 800 °C-60 min have shown better refinement of α-Al at both shorter (2 min) and extended (120 min) holding periods. Minimum and constant DAS (62 μm) is achieved when refined with Al–4B refiner prepared at 800 °C-60 min

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.

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.

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.

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.