Nanotechnology is the key solution for many human problems such as energy conversion, water treatment, and material science. In composite materials, nanoparticles are dispersed in a matrix material such as metals, ceramics, or polymers to enhance their mechanical and thermophysical properties. Polymer nanocomposite materials found their applications in vital fields such as the automotive and aircraft industries. There are many techniques adopted to produce polymer nanocomposites, and they are summarized and discussed according to our best known in this paper. All techniques aim to produce nanocomposite materials with uniform dispersion and without aggregations. Melt-mixing, mixing, in-situ polymerization, electrospinning, and selective laser sintering techniques are the most commonly used techniques to produce polymer nanocomposite. The utilization of water, atomic layer deposition, and plasma-assisted mechanochemistry are found to eradicate the issue of nanoparticles aggregation for melt-mixing technique. Also, sonication with high frequencies plays the same role for mixing techniques. In-situ polymerization provides fabrication of nanocomposites that are thermodynamically stable. Electrospinning represents an effective method which is suitable for producing porous structures. In addition, fabrication of nanocomposites via selective laser sintering has obvious benefits to overcome the problem of aggregation. The working principles of each technique, including the advantages and disadvantages, are discussed.

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Superalloys have magnificent properties which make them widely applied in various industrial fields. They possess high mechanical properties such as high strength, high rupture resistance, and high resistance to corrosion and oxidation. Since they can maintain these properties even at elevated temperatures, they face some problems during the cutting and machining process. They are classified as difficult-to-cut alloys, which means that high heat is generated in the cutting zone due to their poor thermal conductivity. In addition, high friction takes place between the tool and the chip. To overcome these problems during their machining process, different cooling and lubrication techniques using suitable cutting fluids are highly recommended. In this study, the cooling and lubrication techniques that have been applied in the literature to machine superalloys such as dry machining, flood cooling, high-pressure jet machining, minimum quantity lubrication and cooling, and cryogenic machining are reviewed. The technique of each type followed by its advantages and disadvantages are mentioned.