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Aluminum metal matrix composites are potential materials for aerospace and automobile industrial applications due to their enhanced mechanical and tribological properties. Aluminum reinforced with silicon carbide particles has been developed with enhanced mechanical and tribological behavior, but it lacks wettability between matrix and reinforcement causing weak bonding, which reduces the degree of enhancement. The objectives of this study were to fabricate aluminum-based metal matrix composites with enhanced wettability at varying stirring speeds (350, 450, 550 rpm), stirring time (5, 10, 15 min), weight percentage of SiC (0, 5, 10 wt.%), and weight percentage of MoS2 (0, 2, 4 wt.%). Nine samples were fabricated using stir casting based on Taguchi L9 orthogonal array. Hardness, tensile strength, and wear rate of the developed composite were investigated and analyzed as a single response characteristic using Taguchi's signal-to-noise ratio and as a multi-response characteristic using hybrid Taguchi–grey relational analysis (HTGRA). The results revealed that the addition of SiC in the composite produced better hardness, tensile strength, and wear rate. The addition of MoS2 in the composite showed better hardness and tensile strength only up to 2 wt.% of MoS2, and in the case of wear rate, the addition of MoS2 in the composite up to 4% showed better wear resistance. Al–SiC–MoS2 hybrid composite shows better enhancement in hardness, tensile strength, and wear resistance than the Al–SiC composite. [ABSTRACT FROM AUTHOR]

In the current study, an experimental investigation has been done using the hybrid magnetic-field-assisted powder-mixed electric discharge machining (MFAPMEDM) technique to enhance the process performance while machining Inconel 706 superalloy. Inconel 706 is a newly developed superalloy for aircraft applications. All the experimentation work was done according to Taguchi's L9 orthogonal array (OA) to analyse the effect of controlled input parameters like peak current (Ip), pulse 'ON' (Pon) and pulse 'OFF' (Poff) duration on response parameters. Material removal rate (MRR), tool wear rate (TWR) and surface roughness (Ra) were selected as response parameters, and further multi-response optimization was done through grey relational analysis (GRA). GRA results revealed that Pon (62.84%) is the most influential input variable followed by Ip (28.64%) and Poff (8.50%) for controlling all the responses simultaneously. GRA optimized parameters were determined as Ip (5 A), Pon (50 µs) and Poff (20 µs). The surface morphology of the tool (cathode) and workpiece (anode) was assessed using field emission scanning electron microscopy (FESEM), which revealed the presence of partially melted crater boundaries/debris, micro-holes and debris on the surface. The results presented in this paper will help future researchers in studying the machining characteristics of the Inconel 706 superalloy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Adsorption behaviour of pristine GRA, BN, SiC and their in-plane heterostructures towards CO. • Angle strain at the junction of hetero-sheets made them slightly more unstable than the pristine sheets. • Variation in the CO orientation was observed for different sheets leading to the C O stretching frequency shift. • The interactions (physisorption) were dominated by weak Van der Waals forces. • GRA/SiC hetero-sheets showed better sensing behaviour towards CO. A comprehensive study on the sensitivity of graphene, boron nitride, silicon carbide and their in-plane hetero-sheets towards carbon monoxide (CO) was performed using first-principle density functional theory calculations. To rationalize the CO adsorption on pristine and hetero-sheets, molecular electrostatic potential contours, HOMO-LUMO distributions, the density of states plots, atomic charge distributions and quantum chemical descriptors were calculated. The optimized geometries showed that the CO molecule oriented itself at different angles with respect to sheets. A shift in the characteristic vibrational frequency of CO was observed through theoretically computed infra-red spectra. The maximum shift was observed for the GRA/SiC hetero-sheet. Charge analysis showed the partial charge transfer from the CO molecule to the adsorbent sheets. This was further confirmed by the HOMO-LUMO distributions of the interacting species. The reactivity descriptors calculated based on the HOMO-LUMO energies, molecular electrostatic potential contours and DOS plots showed that GRA/SiC hetero-structure exhibited better sensitivity towards CO than other sheets. The calculated adsorption energies, corrected for basis set superposition error, ranged from −3 to −10 kJ mol−1, confirming the physical nature of adsorption. [ABSTRACT FROM AUTHOR]