Metal matrix composites, in particular, Aluminium Hybrid Composites are gaining increasing attention for applications in air and land because of their superior strength to weight ratio, density and high temperature resistance. This paper presents the results of experimental investigation on machinability properties of Silicon Carbide and Boron Carbide reinforced Aluminium 356 hybrid metal matrix composite. The composites were prepared by varying weight fraction of SiC (5%, 10%, 15%) and keeping the Boron Carbide weight fraction (5%) is constant using modified stir casting technique. Four layer coated carbide insert (TiN. Al2O3, TICN, TiN) designated as CNMG 120408 FR was used to machine the fabricated composites. Face centered central composite experimental design coupled with Response Surface Methodology (RSM) was used for modeling that the process output characteristics that influence by weight fraction, speed, feed rate, cutting depth. The experimental results imply that surface Roughness criteria are found to increase with increase of feed. At 0.206.mm/rev feed, the Surface Roughness deteriorated rapidly. Roughness decreases at higher cutting speed during machining. With the help of Mintab software, RSM showed an accuracy of 95%. Moreover, a good agreement was observed between the experimental and the predicted values of surface roughness and cutting force. Optimal cutting condition which leading to the minimum surface roughness and cutting force were highlighted

From the aspect of exploring the alternative lightweight composite material for the aerospace launch vehicle external fuel tank structural components, the current research work studies three different grades of Aluminium alloy reinforced with varying graphene weight percentages that are processed through powder metallurgy (P/M) route. The prepared green compacts composite ingots are subjected to microwave processing (Sintering), hot extruded, and solution treated (T6). The developed Nano-graphene reinforced composite is studied further for the strength–microstructural integrity. The nature of the graphene reinforcement and its chemical existence within the composite is further studied, and it is found that hot extruded solution treated (HEST) composite exhibited low levels of carbide (Al₄C₃) formations, as composites processed by microwaves. Further, the samples of different grades reinforced with varying graphene percentages are subjected to mechanical characterisation tests such as the tensile test and hardness. It is found that 2 wt% graphene reinforced composites exhibited enhanced yield strength and ultimate tensile strength. Microstructural studies and fracture morphology are studied, and it is proven that composite processed via the microwave method has exhibited good ductile behaviour and promising failure mechanisms at higher load levels.