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In this research, synthesis and assessment of the mechanical and wear possessions of Al7049-nano B4C composites are determined by experiments. Using the liquid metallurgy route, a stir casting technique was used to create composites with increasing concentrations of nano B4C from 3 to 9 weight %. Each composite’s reinforcement particles were heated to 400 degrees Celsius before being added to the molten Al7049 alloy in two separate steps, i.e., two-stage stir casting to optimise wettability and distribution. Scanning electron microscopy (SEM) was utilised to examine the microstructure, and energy dispersive spectroscopy (EDS) was utilised to determine the elemental make-up. Mechanical characteristics of composites were determined by subjecting them to tensile, compression, and hardness tests. Wear tests were conducted as per ASTM G99 standards with varying loads and speeds. Nanosized B4C particles were found to be dispersed throughout the sample space in a microstructural analysis. Hardness, ultimate strength, yield strength, and compression strength of Al7049 alloy composites were found to increase significantly as the weight percentage of nano B4C was increased. Additionally, compared to the unreinforced form, the ductility of the Al7049 alloy composites was slightly reduced. SEM micrographs of tensile-fractured specimens were used for research into the field of tensile fractography. Nano B4C reinforced composites exhibited superior wear resistance as compared to Al7049 alloy. These prepared composites can be used for wing root fitting of an aircraft.

Carbon and graphite materials have remarkable characteristics of withstanding high temperatures up to 3000°C in protective environment, good thermal shock resistance, low coefficient of thermal expansion, good thermal and electrical conductivities, low density, etc. These properties make them strong candidates to be used in general high temperature engineering applications. 1,2 However, there are disadvantages such as low strength as compared to various ceramic materials and their limited use in an oxidizing atmosphere above 450°C. Carbon and Graphite materials have low friction values as well. Various techniques have been tried to overcome these problems. These are coating the carbon surface with borates or borosilicates or incorporating different carbides into carbon materials which can increase the oxidation resistance temperature to about 900-1000°C and also decrease wear. 3--6 The development of carbon-ceramic particulate composites is another way to overcome these disadvantages. The incorporation of different ceramics into carbon results in significant improvement in mechanical properties, especially hardness and bending strength, in addition to enhancement of oxidation resistance of the carbon-ceramic composites. 7 Many efforts have been made to prepare carbon-ceramic composites with silicon powder and phenolic resin as carbon precursor. Tang et al 8 reported a three-step process in which silicon powder and phenolic resin were used as raw materials to fabricate silicon carbide powder via coat-mix process. They obtained silicon carbide powders of particle size varying from 0.1 to 0.4 μm with mean particle size of