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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 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.

The demand for high quality materials are increased in the applications of aerospace and automobile industries. The main requirement in the industrial products looking towards the lightweight aluminium (Al) matrix composites lead us to prepare the same with improvisation of physical, mechanical and tribological properties of the composites. In this view the present paper opens up towards the new approach of the utilization of hard ceramic (WC) and soft metallic (Co) blend particulates as reinforcements in Al7075 matrix to prepare the composite via liquid metallurgy route. Composites are prepared for 6 and 9 wt% addition of reinforcement. Samples are characterized by using SEM and EDAX analysis. Evaluation on mechanical properties of the samples over the base alloy exhibits a significant improvement in the tensile strength of the composite material.

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.

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.

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.

Strength of a material is very important factor in selecting the material or alloy for various applications, with this it should also possess good mechanical as well as tribological properties. In this paper, the influence of the heat treatment, load and sliding velocity on the volumetric wear rate of Al-25Mg 2 Si2Cu4Mn alloy was evaluated using a pin-on-disc wear testing machine. Dry sliding wear test were conducted for four different loads (1, 2, 3 and 4kg), for four different velocities (1, 2, 3 and 4m/s). It was observed that the volumetric wear rate decreased with increasing load at constant speed and at constant load with increasing speed the volumetric wear rate increased.

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.