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Aluminium 2024 based Boron fibre and Graphite-based particle reinforced Metal matrix composite (MMC) has been produced by Powder metallurgy (P/M) technique. Four different MMC with composition Al 2024 with 4% and 8% wt.% Boron fiber and 1% of Graphite has been prepared. Die has been designed and fabricated with D3 die steel. ANSYS analysis is carried out to ensure safe working of the die. Optical microscope and SEM analysis was carried out to ensure the uniform distribution of particles. XRD analysis is carried to ensure the composition of the reinforcement particles. The compacting of powders has been done at 550 MPa and sintered in electric muffle furnace at 500°C for 90 minutes. Microstructure and SEM analysis is carried out to investigate the distribution of reinforcement on matrix. It has been found that the reinforcement is distributed uniformly in the matrix. Effects of content (wt. %) on the physical and mechanical properties of composites were determined by measuring the density, hardness and Compression strength values. Both theoretical and actual density has been calculated for MMCs. Also, Porosity has determined and it has been found that as the reinforcement addition increases porosity also increases Microhardness carried out for the MMCs. It has been found that addition of Boron fibre as reinforcement Microhardness increased. Compression test was also carried out and it has been concluded the addition of boron fibre has an effect on the compressive strength but addition Graphite does not contribute much to the compressive strength. The MMCs with 8% wt. Boron fibres has highest compressive strength among the prepared MMCs

In this study, boron fiber powder and graphite is reinforced to Al 2024 alloy to develop hybrid metal matrix composite by stir casting process. Hybrid MMCs developed with different weight fraction for 4%, 6%, 8% and 10% of boron fiber and 2% of graphite. Stirring parameters are optimized to obtain solid casting. Reinforcements are poured into molten aluminium at 15 g/min and stirrer is rotated for 5 minutes at 250 rpm with two stages stirring. 1% of magnesium was added to improve the wettability of Al 2024. Cast samples are machined as per the standards to investigate the microstructure, physical and mechanical properties. Optical and SEM analysis was carried out on machined sample to study the uniform distribution of particles. XRD and EDAX analysis is carried out to confirm the dispersion of particles into the matrix. Uniform distribution of the particles is found in optical and SEM images for these stirring parameters. The peak representation of boron and graphite particles is also observed in XRD and EDAX analysis. Theoretical and experimental density of the cast sample is determined by rule of mixture and Archimedes principle. Result shows the density of the composite decreases by increasing percentage of reinforcements. Micro Vickers hardness was tested on the cast composites and the result showed Al 2024 alloy hardness was increased by 31.25% by reinforcing boron and graphite. Similarly, tensile and compression strength increased by increasing the percentage of reinforcement. Tensile and compression strength of Al 2024 alloy increased by 45.23% and 29.18% respectively. The ductility of the composites decreased by increasing the percentage of reinforcements.

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Developing a new material in the field of aerospace, automobile and machine tool place an important role. The new composites are developed to improve the mechanical, tribological and thermal properties. Composite means combining two or more materials to improve the properties of base material, the base materials are called as Matrix and other materials are called as reinforcements. Stir casting is one of the most economical and simple method to develop new composite. But distribution of reinforcement particles into the matrix material is bit difficult therefore to achieve uniform distribution of reinforcement into the matrix is controlled by controlling the stirring parameters like Stirring Speed, Stirring Temp and stirring time. The present study is focused on developing new composite by stir casting and also studies t he effect of stirring parameters on microstructure and mechanical properties of the composite. Here aluminum is used as a matrix (94% and 90%), boron fiber powder as reinforcement (4% & 8%) and graphite (2%). And XRD analysis shows the presence of reinforcement and also The SEM images show uniform distribution of reinforcement particles in the matrix at stirring temperature of 800c, stirrer is rotated at 250rpm for the duration of 5min and also EDAX images shows the percentage of reinforcement distributed into the base matrix