This optimization investigation focused on the reinforced metal matrix composite of aluminium alloy. Novel of this work is to fabricate the AA6066 composite with HSS and Cu, continually conduct machining tests, and evaluate the tool wear, surface roughness, and thrust force of the stir‐casted specimens. The aluminium composite has 90 percentage of AA6066 alloy reinforcement with six percentage of high‐speed steel and four percentage of copper alloy made by the casting method. The fabricated composites’ turning parameters were optimized through the Taguchi method. The turning operation can be done with the help of the normal lathe with the CBN insert tool. The operation parameters such as feed, depth of cut, and steam pressure of the cutting fluid were considered with three different equal intervals in each parameter. In this investigation, the L9 orthogonal array method is used to identify the optimum values of the turning parameters among the considered machining parameters concerning the response such as wear on the turning tool and thrust forces created on machining. The outcome based on the parameters was identified and mentioned as the rank order for individual and combination of all responses with different conditions. Then, the separate and combined optimized input parameters were provided as the conclusion.

In the current scenario, many natural fibers available in the world can be used in various applications in the day-to-day life of biomedical products, automobile parts, industrial products, etc. Biocomposites can replace or serve as a framework allowing the regeneration of traumatized, degenerated tissues, and organs, thus, improving the patients’ quality of life. This research work is aimed at fabricating and investigating the natural biopolymer composites for biomedical applications. There are two sets of fiber composites fabricated in this research work. Ramie fiber considers a common base fiber for both composites. Hemp fibers and coir fibers were considered as filler in this research work. Biodegradable and bioresorbable polypropylene resins are used to fabricate the biocomposite using the compression moulding technique. Different proportion specimen mechanical properties were compared for bone fixtures and joint applications. The contour plots and bar charts were plotted to identify the variations in the volume percentage. The individual fiber specimens also have significant properties when compared with the composite fibers. Then, the individual superior property-based combinations such as hemp and coir fiber mixed with biodegradable and bioresorbable polypropylene/ramie fiber were recommended to produce joints and bone fixtures to alleviate pain for patients.

Aluminium alloy (Al7075) based hybrid metal matrix composites reinforced with Silicon carbide (SiC) and Tungsten carbide (WC), at 5 wt% each are considered for this investigation, which are developed by stir casting methodology. Material characteristic analysis both at micro and macro (Tensile strength and micro hardness) level were performed. This investigation is further progressed with drilling of the composites using titanium aluminium nitride coated carbide drill (5mm diameter) for varied point angle, feed rate and drill speed. The responses such as thrust force, surface roughness and roundness error were investigated by adopting Response Surface Methodology (RSM). Multiple linear regression (MLR) is developed along with Artificial Neural Networks (ANN) model for predicting the outputs. Scanning Electron Microscope (SEM) image reveals the uniform distribution of ceramic particles in matrix which ascertains enhanced mechanical properties. The parameters such as feed rate and point angle are found to have significant influence during drilling process. The roundness error is found higher with higher point angle which is due to the wider cutting edges in the drill bit. For unconstrained multi-objective optimization, the optimal condition obtained are 128°- point angle, 0.05 mm rev⁻¹ feed rate and 1000 rpm drill speed. For constrained optimization (roundness error ≤0.05 mm), optimal conditions are 118° point angle, 0.05 mm rev⁻¹ feed rate and 1000 rpm drill speed.

Nanocomposites are preferred for performance enhancement over micron composites because of their better performance in enhancing the desired properties of the parent material. Nano-silicon carbide and nano-graphite are considered together for reinforcement of Al7075 in this piece of research. Here, the purpose of reinforcement of graphite considered is to improve machinability. The stir casting was employed for fabrication of nanocomposite. The composite matrix includes Al7075 matrix material, reinforcement material of nano-SiC (5wt.), and nano-graphite (5wt.). Wire cut Electrical Discharge Machining (WEDM) of the synthesized nanocomposite SiC/Gr/Al7075 is considered for investigating the machinability. The objectives of the study are to synthesize the novel nanocomposite and optimize the process parameters to minimize the kerf width during WEDM. The independent variables like choice of wire electrode including the uncoated brass wire, diffused annealed wire, and zinc coated brass wire were considered along with operating parameters like gap voltage, pulse-off time (T_off), and pulse-on time (T_on). The response surface methodology (RSM) is used for designing experiments and analyzing and optimizing independent parameters of WEDM for minimizing the kerf width. Experimental results reveal that the machinability performance of the novel nanocomposite in WEDM with zinc coated brass wire was the best and produced minimum kerf width with the optimized inputs of 117μs pulse-on time, 60μs pulse-off time, 160A input current, and 10volt gap voltage.

Machinability investigation of new material is one of the mandatory investigations to complete the purpose of creation of it. Electrical discharge machining (EDM) is one of the promising unconventional machining processes for highly accurate machining performance in difficult-to-cut material even machining complicated profiles. The powder-mixed EDM and nanopowder-mixed EDM are the improved versions of the EDM. The AlZnMg composite is reinforced with Si₃N₄ (9 wt. ) for meeting automotive and marine applications. The aluminium nanoparticles enhanced deionised water was used in NPMEDM. The nickel-coated brass and uncoated brass tube electrode were considered for the investigation. Pulse on time (µs), voltage (V), input current (A), and capacitance (nF) were independent variables and varied at 3 levels. The microhole machining performance with a coated and uncoated electrode was investigated. The L18 orthogonal array involved in the experimental design, material removal rate, and electrode wear rate were analysed. The SEM analysis was employed in the surface morphological study of electrodes before and after machining. The input parameters were optimised for the coated electrode for the responses of MRR and EWR.

This study investigated the mechanical and microstructural properties of ZrO₂ reinforced titanium metal matrix composites (TMMCs) fabricated using powder metallurgy. The base matrix of the Ti6Al4V alloy was reinforced with ZrO₂ at mixing proportions of different wt percentage points at 0, 3, 4, 5 and 6. Microstructure evaluation was carried out to study the bonding characteristics of the matrix and reinforcement, and it was confirmed that the reinforcement was homogenously mixed with the base matrix. The objective is to study the effect of zirconia on mechanical properties such as hardness, compression strength and thermal expansion coefficiency of Ti6Al4V alloy. The hardness, compression strength, and shrinkage rate are increased with the increase of ZrO₂. Finally, it was observed that, 6 wt percentage of ZrO₂ reinforced composite showed better characteristics in that the hardness and compression strength were the highest among all the proportions used and the coefficient of thermal expansion was low. Due to these promising results, the fabricated ZrO₂ reinforced Ti6Al4V composite can be a potential material for structural, aerospace and automotive applications.