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Item Tribological Response of Magnesium/Glass Microballoon Syntactic Foams(Springer Science and Business Media Deutschland GmbH, 2022) Manakari, V.; Parande, G.; Doddamani, M.; Srivatsan, T.S.; Gupta, M.Magnesium (Mg)-based materials have great potential to replace the existing aluminum alloys and steels used in applications spanning the industries of defense, aerospace, and automotive due in essence to their excellent specific strength [σ/ρ], damping characteristics, and impact resistance. In this research study, we design an ultralow density magnesium/glass microballoon (GMB) syntactic foam having a density of 1.47 g/cc using the technique of Disintegrated Melt Deposition (DMD). The resultant material offered a healthy combination of extraordinary properties outperforming the existing aluminium and iron syntactic foams in terms of a noticeable improvement in specific strength [σ/ρ]. Further, the wear resistance of magnesium under dry sliding conditions showed a significant enhancement (~2.5 times) following the addition of glass microballoon (GMB). Abrasion and oxidation were identified to be the dominant wear mechanisms post worn-surface analysis. Morphology of the worn specimen provided clean, clear, and convincing evidence for the occurrence of delamination wear, which has traditionally limited the competitive advantage of magnesium and its alloy counterparts for selection and use in safety–critical components in transportation vehicles. This can be effectively overcome by the development of the proposed syntactic foams, which provide a unique cushioning effect against the applied load. © 2022, The Minerals, Metals & Materials Society.Item Fundamentals of multifunctional nanostructured coatings with recent updates(Elsevier, 2025) Poddar, M.K.; Soman, V.This chapter provides a comprehensive overview of nanocoatings and their diverse applications. Nanocoatings are characterized by their nanoscale dimensions, typically ranging between 1 and 100nm and high-surface-to-volume ratios. They showcase remarkable properties such as protection against corrosion, wear, microbial action, and UV radiation and provide superior optical, electrical, and surface properties. Compared to the conventional coatings, the synthesis of nanocoating involves very little use of volatile organic compounds. Nanocoating is fabricated using synthesis techniques like chemical vapor deposition, electrodeposition, and Particle Vapor Deposition, etc. This chapter also discusses different types of nanocoatings reported in scientific literature, each with many applications. Ceramic-based nanocoatings, which are oxide-based ceramics like alumina (Al2O3), zirconia (ZrO2), and titania (TiO2), etc, are highlighted for their remarkable hardness and suitability for wear and corrosion-prone applications. Also, the applicability of polymer and metal matrix-based nanocoatings in packaging, automotive, thermal protection, and solar energy harnessing is emphasized; these nanocoatings find extensive potential in industries such as aerospace, transportation, and manufacturing, where superior mechanical properties and wear resistance are inevitable. To bring nanocoatings to a large scale in the future, it is essential to adapt cost-effective strategies and evaluate the adhesion between substrate and coating. Mathematic models may be developed to simulate various properties. Nature-inspired models could efficiently design nanocoatings, such as the lotus leaf effect. We also address some of the environmental challenges associated with nanocoating and emphasize the importance of considering factors like size, capping agent, and shape to mitigate such challenges. Nanocoatings offer great potential in enhancing material performance, protecting surfaces, and addressing industry challenges. © 2025 Elsevier Ltd. All rights are reserved.Item Tribological Performance of Fe-Based Composite Coatings Under Elevated Temperature Conditions(Springer, 2025) Chandramouli, T.V.; Joladarashi, S.; Ramesh, M.R.The present study investigated the tribological performance of Fe-based coatings reinforced with carbides onto a maraging steel substrate using the HVOF spray technique. These materials are widely used in manufacturing various components in the aerospace and energy sectors. Commercially available SS316L and 17-4PH are reinforced with WC–Co feedstock powders to deposit these composite coatings on maraging steel substrate. The dry sliding wear tests were conducted using the ball-on-disc tribometer at varying temperatures (25 and 300 °C) with 10 N normal load using an alumina ball (Al2O3) as the counter body. The study includes micro-hardness, porosity, density, bond strength, and surface roughness of the coatings. The samples subjected to wear testing were analyzed using SEM/EDS and XRD techniques, and the wear scar volume was measured using a 3D profilometer to calculate the volume metric loss. The wear rate of SS316L30%WC–Co is 64.46% lower than that of 17-4PH30%WC–Co at room temperature and 67.33% lower at 300 °C under a load of 10 N. At room temperature, the worn surface exhibited abrasive wear, while at 300 °C, adhesive wear and oxidative wear were observed owing to the formation of protective layers. Therefore, SS316L-30%WC–Co demonstrates superior wear resistance compared to 17-4PH-30%WC–Co and offers enhanced mechanical strength, particularly in challenging environments. The deposition of these coatings effectively protects the maraging steel substrate. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2025.Item Tribological aspects of Al and Mg composites(Elsevier, 2025) Koppad, P.G.; Joladarashi, S.; Ramesh, M.R.; Keshavamurthy, R.It is well known that the technical function of a large number of engineering components/parts depends on motion. However, the term motion here is not as simple as it sounds, because it comes with consequences in the form of friction and wear. Along with lubrication, the science that deals with friction and wear is known as tribology. Therefore, it is necessary to pay more attention to tribology and acquire knowledge on the tribological behavior of materials, as the tribological characteristics such as friction and wear have been causing poor efficiency in engineering structures, huge economic losses, and environmental impacts. One way of addressing these issues lies in the development of lightweight materials based on metals such as aluminum and magnesium. Although one cannot employ these metals in their pure form, but modification in their microstructure and properties can certainly address the needs required for tribological applications. Keeping this in mind, this chapter covers the properties of aluminum and magnesium metals, basic aspects of tribology and most importantly, the work carried out on the friction and wear behavior of aluminum- and magnesium-based composites. The importance of this chapter lies in promoting better knowledge of the tribological behavior of aluminum and magnesium composites, especially from a various wear parameters point of view. The influence of material composition and wear parameters on tribological behavior is covered with a follow-up section on numerical and optimization methods employed for predicting tribological characteristics. © 2026 Elsevier Inc. 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