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The effect of grain refiner on microstructural features, casting defects, formation of precipitates and eutectic Si particles, which influence the hardness and tensile properties of Al-Si alloys, is investigated in this study. The A-7Si alloy was prepared through melting and casting route with varying wt.% of Ti up to 0.2%. XRD, SEM and HRTEM analyses characterize the phases and aluminide (TiAl3 and Ti7Al5Si12) precipitates. The thermodynamic analysis, carried out by using FactSage software, confirms the presence of aluminides particle in the microstructure, which is formed at the liquid stage. The microstructure of as-cast Al-7Si alloy contains primary α-Al phase with dendritic morphology and eutectic phase having plate-like eutectic Si particle which is distributed at interdendritic regions. The morphology of primary α-Al grains is altered from dendrite network to fine equiaxed rosette type structure. Secondary dendrite arm spacing (SDAS) is reduced after adding grain refiner (Al-5Ti-1B) to the Al-7Si alloy. The eutectic Si is also refined to fine fibrous type particles. The shrinkage porosity and microcracks are also reduced after the addition of a grain refiner. The yield strength, ultimate tensile strength and elongation to fracture increase from 84, 117 MPa and 16% to 112 MPa, 148 MPa and 22%, respectively, after the addition of 0.1% Ti due to significant reduction in SDAS. Elongation decreases when the percentage of Ti increases more than 0.1%. The fracture mechanism of grain-refined alloy is changed from brittle to ductile fracture.

The present manuscript has proposed a capacitance-based model of dual material gate charge plasma-based vertically t-shaped Tunnel Field Effect Transistor (DMG V-tTFET) with spacer regions. The surface potential model, which modulates terminal capacitance and the drain current model is used to analyse the Poisson Equation (PE). For modelling the n-type channel, the inclusions are an enhancement-mode, accumulated charges, and ionized impurity charge carriers. The spacer region’s surface potential and channel region potential are inspected with modelling whose outcomes are authenticated by the simulations in the Silvaco TCAD software for various boundary conditions. The potential model is found by allocating the proposed device into ten distinct units and applying the 1-Dimensional (1-D) and 2-Dimensional (2-D) PE in their respective sections. To resolve the PEs for different sections, the parabolic approximation method is employed. The impact of geometrical variety, for instance, the spacer length and tunnelling width are analysed with dependence upon the electrical characteristics of DMG V-tTFET. The surface potential of greater than 0.75 V at a power supply voltage of 0.5 V is attributed to the establishment of an energy barrier in the channel with optimal device parameters.

The present study aims at development of nano-AlN reinforced aluminum metal matrix composite through stir casting method. For this commercially pure aluminum (CP-Al) and CP-Al + 2 wt% AlN nano-composite were casted at 760 °C by stir casting method. Both the alloy and the composite were subsequently characterized using optical microscopy and scanning electron microscopy. They were further tested for mechanical properties and dry sliding pin-on-disk wear studies were carried out at three different loads at room temperature at 200 rpm up to a sliding distance of 2 Km. The results indicate good particle dispersion into the matrix and massive grain refinement in the nano-composite. Accordingly, there is an improvement in UTS and 0.2% YS values by more than 100% by keeping ductility unaffected in the composite compared to the base alloy. Grain refinement and strengthening effect of nano-particles are the reasons for this improvement. Moreover, the wear study reflects considerable improvement in wear resistance in the composite at all loads. Suppression of adhesion (at all loads) and plowing abrasion (at 60 N load) are attributed to this improvement in wear resistance in the composite.

In this work, a novel design of ArcTFET based on Charge-Plasma and Gate-Stack (CP-GS-ArcTFET) is proposed for the first time. The precise detection of breast cancer biomarker (C-erbB-2) through serum should not be limited by HEMT devices but should be explored with other novel devices also. In this regard, investigation in above-mentioned device is carried out for the detection of C-erbB-2 protein. In CP-GS-ArcTFET, various central angles (θ) are considered for observing the electrical parameters e.g., drain current (I

An efficient analysis of time-modulated array (TMA) toward realizing less-attenuating radiation patterns with simultaneously suppressed sidelobe and sidebands is presented in this paper. In this framework, an optimal outer element-controlled time sequence is derived. The proposed time scheme, along with optimized array excitations, is profitably applied for the desired solution. TMAs are considered unconventional alternatives to the phased arrays. The desired array radiation features can be attained by periodically enabling and disabling the array elements through high-speed switches. Despite the advantages of architectural simplicity and real-time reconfigurability of periodic time sequences, time-domain antenna arrays inherently generate unavoidable sideband radiations (SRs). The undesired SRs obtained at multiple harmonics around the carrier frequency of the array resembles power loss in unintended directions. This paper aims to minimize the SRs as well as the sidelobe level (SLL) for an efficient analysis of time-modulated linear array (TMLA) with high-directive radiation patterns. The starting instants and the period of on-times are optimized to generate a unique shifted time scheme for the edge elements of the TMLA to reduce the sideband levels (SBLs). The array excitations and the uniform spacing between the elements are also optimized together with the shifted time scheme for the coveted solution. Other methods of suppressing SLLs and SBLs with shifted pulse schemes and sub-sectioned pulse schemes are also presented for a fair comparison. Modified versions of the particle swarm optimization algorithm (PSO) are applied for the desired solutions. The optimal results attained by wavelet mutation-based novel PSO is compared with the conventional PSO and the modified novel PSO-based results. The representative results are reported, and the superior performance abilities of the proposed method compared to other published studies are assessed.