In this study, SU-8 and its composites are fabricated by blending 10 wt.% hexagonal boron nitride (h-BN) fillers with/without lubricants, such as 10 wt.% base oil (SN150) and 20 wt.% perfluoropolyether (PFPE). The thickness of SU-8 and its composites coating is fabricated in the range ~100-105 μm. Further, SU-8 and its composites are characterized by a 3D optical profilometer, atomic force microscopy, scanning electron microscopy, a thermal gravimetric analyzer, a goniometer, a hardness tester, and an optical microscope. Under a tribology test performed at different normal loads of 2, 4, and 6 N and at a constant sliding speed of 0.28 m/s, the reduction in the initial and steady-state coefficient of friction is obtained to be ~0.08 and ~0.098, respectively, in comparison to SU-8 (~0.42 and ~0.75), and the wear resistance is enhanced by more than 103 times that of pure SU-8. Moreover, the thermal stability is improved by ~80-120 °C , and the hardness and elastic modulus by ~3 and ~2 times that of pure SU-8, respectively. The SU-8 composite reinforced with 10 wt.% h-BN and 20 wt.% PFPE demonstrated the best thermo-mechanical and tribological properties with a nano-textured surface of high hydrophobicity.

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Remarkable progress has been established in the field of nanoenergetic materials (mixture of nanoscale fuel and oxidizer) since the advent of nanotechnology. Combustion of nanoenergetic materials depends on many key factors like synthesis route, equivalence ratio, morphology of constituents, and arrangements and handling of materials. For tailoring and tuning of the combustion properties of nanoenergetics, sound knowledge of the reaction mechanism is needed; in this review article a schematic study on the reaction mechanism is presented. By employing various routes and strategies in synthesizing and nanoengineering of the fuel or/and oxidizer to realize a significant evolution from normal physical mixing of nanopowders to the formulation of core/shell nanostructures, the nanoenergetic materials achieved the best ever combustion properties in terms of combustion reactivity, ignition sensitivity, energy density, etc. Overall, in this article, a critical state-of-the-art review of the existing literatures has been conducted to feature the main developments in the molecular combustion modeling of melting, oxidation, and core–shell reaction/diffusion of nanoaluminum and the molecular modeling of combustion reactivity and ignition sensitivity of nanoenergetic materials.

In this study, epoxy resin blended with graphite/talc micro fillers are used to fabricate the composite bearing balls of uniform diameter of 12.7 mm. These bearing balls were tested in four ball test rig for investigation of friction and wear. The fabricated composite bearing ball of composition graphite (10 wt%) /talc (10 wt%)/epoxy demonstrated a significant reduction by ∼63% in coefficient of friction and a moderate increment by ∼34% in wear resistance as compared to pure epoxy bearing ball under dry condition. Further, the compressive strength and hardness test were carried out on the composite bearing balls which revealed a reduction in compressive strength after adding the fillers but approximately similar compressive strength and a marginal improvement in hardness by ∼5% was exhibited by graphite (10 wt%)/talc (10 wt%) /epoxy composite bearing ball with respect to pure epoxy bearing ball. Hence, the fabricated polymer composite bearing balls can be implemented for low to moderate load bearing application with enough capability to eliminate the bulk lubrication requirements as in case of conventional metallic bearing balls.

Al-7075/Si3N2/ZrO2 hybrid metal matrix composite is developed using stir casting method. The mechanical behaviour of the developed composite is carried out using impact test, tensile test and hardness test as per ASTM standards. The micro structural analysis shows that the grain boundaries is having inter-dendritic network of silicon nitride and zirconium oxide particles and it is distributed uniformly in an aluminium matrix. Furthermore, a considerable increment in the tensile strength, hardness and wear properties of the hybrid composite was observed with increasing the percentage reinforcements of zirconia (2, 4 and 6wt%) in Al-7075/Si3N4 composite (keeping a constant percentage of Si3N4 of 8wt%).