The current paper will look at the effects of different Silicon content on the phase stability, microstructural behaviour and mechanical response of AlCrMoNbVSix lightweight refractory high-entropy alloys (LRHEAs). In addition, Si-based alloys (x = 0, 0.25, 0.50, 0.75) were prepared and characterised through X-ray diffraction, which confirms that the four compositions have retained body-centred cubic (BCC) solid-solution matrix, with lattice constant decreasing slightly between 3.145911 Å with the base alloy to 3.123767 Å. The results obtained in SEM-EDS indicate a close, homogeneous distribution of elements in the base alloy, and a gradual addition of Si also causes a serious elemental segregation between the interdendritic and the dendritic regions. Mechanical tests indicate a strong increase in the yield strength, which goes up to about 1610 MPa in the Si-free alloy, to approximately 2090 MPa with x = 0.75, though this strengthening is accompanied by a decrease in the compressive strain at fracture of nearly 24.6 to approximately 16.5. Hardness increases positively with addition of Si as solid solution strengthening by increasing lattice distortion but at the cost of ductility, which is a strength ductility trade off. These results demonstrate that moderate Si is a segregating material that enhances the stability of the phase, and optimization of the composition is required to balance mechanical performance and structural integrity in the challenging LRHEAs application.

This research is focused on the influence of silicon (Si) addition on the structure, mechanical properties, and corrosion behavior of refractory high-entropy AlTiNbVCrSix (x = 0-0.75) alloys. XRD data indicate that the base alloy is single-phase BCC, whereas the addition of Si results in the formation of other silicide phases, which complicates the structure. The SEM analysis establishes that the microstructure is finer and more heterogeneous as more Si is added and the Si-rich regions appear. There is also a slight reduction in density because of the lower atomic weight of Si. Mechanically, the hardness and compressive strength increase with the increase of Si content. This improvement is mainly attributed to the formation and increasing volume fraction of hard silicide phases, while solid-solution strengthening arising from Si-induced lattice distortion provides a comparatively secondary contribution. However, the alloys become more brittle at higher Si levels, leading to reduced ductility during compression. Corrosion behavior in 3.5 wt.% NaCl solution indicates a definite enhancement with addition of Si. The corrosion potential becomes more positive and the density of corrosion current becomes significantly lower. The upright performance observed in the alloy with 0.75 Si implies that it has the highest corrosion resistance. This is mainly due to the formation of a stable and protective oxide layer that limits metal dissolution.

In this investigation, a single-pass hot compression method was applied to modify the as-cast microstructure of the Co12.5Cr12.5Cu12.5Fe12.5Ni37.5Si12.5 high-entropy alloy (HEA) with the goal of achieving a significantly homogenized microstructure with reduced dendritic segregation. High-temperature compression tests were conducted within a thermo-mechanical window of 800-950 °C and at a strain rate ranging from 0.01 to 10 s⁻1, up to a maximum true strain of 0.92. The stress–strain responses showed that the flow stress increased significantly with decreasing deformation temperature and increasing strain rate. These stress variations were governed by deformation parameters (temperature, strain-rate, and net-strain) along with precipitate coarsening effects. To capture and predict the alloy’s deformation characteristics, a constitutive analyis based on the Arrhenius-type equation was implemented in combination with a three-dimensional processing map. The model estimated a strain-hardening exponent of 4.329 and an average activation energy for hot deformation of 425 kJ/mol. This value is higher than that reported for conventional FCC alloys ( 250-350 kJ/mol) and CoCrFeNi-based HEAs ( 300-400 kJ/mol), indicating increased resistance to deformation due to severe lattice distortion, multicomponent interactions, and presence of Ni-Si stregthening phase. Workability analysis using the modified dynamic material model (MDMM) revealed that power dissipation efficiency (PDE) progressively increased with strain, reaching about 60

This work focuses on W-0.4MoNb1.3TaTiCrx (x = 0, 0.25, 0.5, 0.75 at.%) refractory high-entropy alloys produced by vacuum arc melting. Their microstructure, mechanical behaviour and corrosion performance were systematically examined. X-ray diffraction and SEM confirmed a body-centered cubic matrix, with Laves phase formation increasing at higher Cr levels. A slight reduction in the lattice parameter and peak shifts toward higher angles indicated the substitution of larger atoms by smaller Cr atoms. Solid-solution strengthening analysis highlighted Cr's role in enhancing strength. The alloy with x = 0.75 achieved the highest yield strength (similar to 1550 MPa) but exhibited reduced ductility (similar to 10% fracture strain) due to brittle intermetallic phases. Corrosion tests in 3.5 wt.% NaCl showed improved resistance with Cr addition, attributed to the protective Cr-rich oxide layers. Overall, Cr significantly influences phase stability, mechanical properties, and electrochemical behaviour, offering pathways for optimizing RHEAs for demanding structural applications.

To enhance the mechanical properties of refractory high-entropy alloys (RHEAs), Laves intentionally introduced with body cantered cubic (BCC) structure, and NbMoTiVCrx (x = 0, 0.25, 0.50, and 0.75, molar ratio) alloys were synthesized via vacuum arc melting. The results show that the formation of Laves phase significantly influences hardness, compressive properties, and corrosion behaviour. The hardness increases systematically with Cr addition due to Laves phase strengthening and microstructural refinement, reaching its maximum at x = 0.75, consistent with the increase in Laves phase volume fraction from 0 to 15%. Compression testing shows that the yield strength and ultimate compressive strength increase markedly from 880 MPa to 1720 MPa and from 1660 MPa to 2380 MPa, respectively, with increasing Cr content. Finally, electrochemical measurements demonstrate that Cr addition does not compromise corrosion resistance; instead, the formation of stable passive films contributes to improved corrosion performance in chloride media. The simultaneous enhancement in hardness, compressive strength, and corrosion resistance confirms that controlled Laves phase formation is an effective strategy for designing NbMoTiV based RHEAs with improved overall performance.

This study examines the impact of silicon addition on the microstructure and properties of CoCrFeMnNiSix (x = 0-0.9) high-entropy alloys fabricated by vacuum arc melting. XRD confirms a single FCC solid solution for all x, with the lattice parameter increasing from 3.545 & Aring; (x = 0) to 3.575 & Aring; (x = 0.9) and diffraction peaks shifting to lower 2 theta. SEM/EDS shows Si-accentuated dendritic/interdendritic partitioning and refinement. Microhardness increases from 150 HV (x = 0) to 400 HV (x = 0.9), consistent with solid-solution and grain-boundary strengthening. Dry sliding tribology shows the steady-state friction coefficient decreases from 0.57 to 0.39, while the peak friction drops from 0.92 to 0.75. In 3.5 wt.% NaCl, corrosion performance improves markedly. Ecorr shifts from -360.6 to -247.3 mV and Icorr decreases from 1.16 & times; 10(-5) to 2.45 & times; 10(-7) A cm(-2) for x = 0 to x = 0.9. Silicon thus enables concurrent FCC lattice expansion, microstructural refinement, higher hardness, better wear response, and superior corrosion resistance.

This study investigates the microstructural and mechanical effects of incorporating 1.5 wt

High-entropy alloys (HEAs) based on CoCrFeMnNi continue to attract attention to their balanced mechanical properties and corrosion resistance; however, their tribological response remains strongly path-dependent. This review combines processing routes such as casting, powder metallurgy/spark plasma sintering (SPS), additive manufacturing (SLM/LPBF), and coating methods such as PVD/thermal spray with the resultant phase constitution (FCC, BCC, σ, and Laves) and defect structures to describe their trends in hardness, friction, and wear at room temperature up to approximately 800 o C. To balance different literature reports, we standardize the units of wear and cluster complete test data (counterface, load, kinematics, atmosphere, and temperature) so that quantitative comparison between studies is possible. Determining (i) systematic decreases when the FCC changes to BCC or intermetallic-reinforced state and (ii) a crossover in temperature at which many coating types can minimize wear at approximately 400 o C before increasing in temperature, a causal map was constructed linking route-controlled phase selection and secondary reinforcers (e.g., carbides/solid lubricants) to effect sizes in selective wear and friction. A route-selection guide, important information gaps in tribocorrosion (sliding-electrochemistry coupling), and template reporting tools that improve design and reproducibility are included at the conclusion of the review. All these factors lead to a consistent foundation on which to build the engineering of Cantor based HEAs and coating to meet desired wear windows in commercial environments.

Enhancement in heat transfer can be realized by adding nanoparticles to boost the thermal properties of the base fluid, increase the tube surface area, and modify the flow trajectory of the fluid. In the present investigation, the convective heat transfer and pressure loss characteristics of Al2O3-Ethylene glycol and Al2O3-Water-based nanofluid in the vertically positioned helically coiled tube with micro-fin are studied by ANSYS FLUENT 19.2 through numerical methods. The effects of nanofluid mass fraction (1–4

This study examines the effect of silicon (Si) addition on the microstructure, mechanical properties, and corrosion behavior of Ti4Al,.5Cr,.5V,.5Nb,.5Six (x = 0-0.75 at. ratio) refractory high-entropy alloys (RHEAs) synthesized via vacuum arc melting. The base alloy exhibited a single-phase BCC structure, while Si addition promoted the formation of hard M5Si3 silicide. At 0.25 Si, the alloy achieved superior mechanical performance, with enhanced strength and ductility resulting from solid solution strengthening, grain refinement, and fine silicide dispersion. However, higher Si contents (0.50 and 0.75) led to increased brittleness due to coarse silicide growth and elemental segregation. Corrosion resistance improved initially due to stable passive film formation but deteriorated at higher Si levels owing to micro-galvanic effects and structural inhomogeneity. These results highlight that optimized Si incorporation (x = 0.25) offers a strategic pathway to develop lightweight, highstrength RHEAs with balanced mechanical integrity and corrosion resistance for extreme service environments.

This paper investigates a simple and feasible pseudo-binary approach for creating composite-structured high-entropy alloys (CSHEAs), based on two important parameters: mixing enthalpy (Delta Hmix) and valence electron concentration (VEC). By employing this method, a series of CSHEAs (CoCrCuFe2Ni2Si, CoCrCuFeNi2Si and CoCrCu1.5FeNi2Si) composed of intermetallic compounds and face centred cubic (FCC) phase were successfully synthesized through vacuum arc melting route. Elemental analysis and scanning electron microscopy (SEM) revealed that the intermetallic compound is enriched in Ni-Si, while the face-centred cubic phase is composed of Co, Cr, Cu, Fe, and Ni. All the alloys employed possess outstanding hardness, wear resistance, and corrosion resistance. The design parameters that were previously provided for the high-entropy alloys with a composite structure are in good agreement with the current research. This pseudo-binary approach presents a viable approach to the design of CSHEAs with customized properties, enabling opportunities for the creation of cutting-edge materials with improved performance.

The present work examines how varying aluminum content influences the structure, strength, and wear response of AlXMoNbTiV refractory high-entropy alloys (HEAs) (x = 0, 0.5, and 1). X-ray diffraction confirms that all three compositions retain a body-centered cubic solid-solution matrix, while the lattice constant contracts slightly from 3.26 & Aring; for the base alloy to 3.251 & Aring; when Al reaches one atomic ratio. Al addition also refines the dendritic solidification pattern and promotes more uniform elemental distribution. Mechanical tests reveal a pronounced rise in yield strength, increasing from about 902 MPa in the Al-free alloy to roughly 1.59 GPa at x = 1, but this strengthening is accompanied by a reduction in compressive strain at fracture from nearly 40% to about 11%. Hardness follows a similar upward trend with Al addition. Dry-sliding wear experiments demonstrate that the alloys containing Al show more than a 30% decrease in wear rate relative to MoNbTiV. This result is attributed to higher hardness, microstructural refinement, and the formation of stable surface oxides during sliding. These outcomes highlight the potential of carefully tuned Al additions to produce lightweight, oxidation-resistant refractory HEAs with a favorable balance of mechanical performance and surface durability for demanding high-temperature applications.

The work focuses on developing a new low-density steel nanocomposite with a composition of 66.75

The COVID-19 pandemic has impacted individuals worldwide, with each patient experiencing varying symptoms such as fever, body aches, loss of taste, and reduced appetite. Following recovery, many patients report diverse side effects influenced by factors like body composition, infection severity, and pre-existing health conditions. Researchers globally are examining both short- and long-term effects of COVID-19 on various organs to enhance drug quality, safety measures, and preventive protocols. This study investigates the correlation between COVID-19 severity and its side effects through an empirical model. The model evaluates key parameters, including C-reactive protein, cycle threshold value, chest CT scan scores, oxygen levels, hemoglobin, white blood cells, red blood cells, D-dimer, and vitamin D3 and B13 levels, based on historical data and manual analysis of patient reports. Computational tools were developed to estimate these parameters and assess their relationship with COVID-19 severity. Tested on over 100 patients with varying severity levels, the study found strong correlations for CTV, RBC, WBC, D-dimer, D3, and B13 levels. Clinical validation demonstrated 91% accuracy, highlighting the model’s potential for real-time application. These findings contribute to a deeper understanding of COVID-19’s health impacts and support improved patient care strategies, in comparison to previous work which only focused on image-based research which is more time consuming and cost ineffective.

Globally, emissions from various energy production and industrial processes contribute a significant amount of carbon dioxide to the atmosphere. The build-up of CO2 in the atmosphere is the primary cause of global warming and related climate changes. Therefore, it is essential not only to control the emission but also to remove it from the atmosphere. All human-induced processes must follow a zero-carbon budget to achieve this. Further, future economic growth and policies must ensure a carbon-neutral approach of no net gain in the atmospheric carbon pool. In this context, the natural or anthropogenic process of transferring and storing atmospheric CO2 (which would otherwise remain in the atmosphere) into other long-lived carbon pools is called carbon sequestration. This chapter deals with the carbon sequestration options, methods and challenges. It also briefly explains the chemical conversion of CO2 into methanol.

The impact of the metalloid element silicon (Si) addition on the microstructural and mechanical properties of the AlCoCuCrFeNiSix high-entropy alloy system is examined in this paper. The alloys were synthesized using a vacuum arc melting route. X-ray diffraction was used to analyse the current high-entropy alloys' phase formation to comprehend the alloying process's behaviour. It is evident from the peak pattern of the X-ray diffraction that the inclusion of Si promotes the growth of body-centred cubic structures. The microhardness and wear resistance were increased by increasing the Si content from 0 to 0.9. Si presence enhances the hardness of the alloys and strengthens the grain boundary. Improved hardness and wear resistance results from the enhanced body-centred cubic-phase formation, which poses a barrier to the dislocation movement and prevents further deformation. Furthermore, the inclusion of Si improved corrosion resistance in potentiodynamic polarization measurements. Excellent compressive strength is possessed by all of the high-entropy alloys with Si addition.

A multi-component category of an alloy containing very specific properties revolutionized the area of material science and the present engineering era. Laser cladding, a technique for surface coating, enhances surface quality and modifies properties using advanced coating technologies. In current trends, Laser cladding is mainly used in equipment and machine parts for enhancing surface properties, repairing damaged parts and surface coating caused by its advantages such as small heat-affected zone, low substrate damage, low dilution rate and exceptional metallurgical material bonding among coating and used substrate. Laser cladding improves substrates’ mechanical and various functional-specific properties, ensuring a high-quality balance between mechanical and surface attributes. The research society was able to investigate laser-cladding HEAs coatings because of the superior attributes of HEAs compared to ordinary alloys. This paper reviews current developments in laser-cladding HEAs coatings and the application of laser-cladding technology to HEAs materials. The laser cladding high-entropy alloy coatings have potential applications in corrosion, wear, and oxidation resistance, as well as their respective substrates. Cladded coatings composed of HEAs materials are measured to have shown potential applications in recent technology, opening exciting possibilities for the future. The study also discusses current trends and future prospects.

This paper examines the impact of silicon in the AlCrFeMnNi high-entropy alloy system, focusing on both its microstructural and mechanical properties. Alloys with varying silicon content (x = 0, 0.3, 0.6, 0.9 atomic ratio) were synthesized using vacuum arc melting. The phase formation of these high-entropy alloys was analyzed using x-ray diffraction to comprehend the alloying process behaviour. The findings revealed that the solidification of the AlCrFeMnNi alloy occurred in dendritically, with dendrite cores containing Cr, Fe, and Ni, while interdendritic regions were enriched in Al and Ni after adding Silicon. Increasing the silicon content from 0 to 0.9 led to significant improvements in microhardness and wear resistance. This improvement is attributed to the reinforcement of grain boundaries provided by silicon. The formation of an Al and Ni rich B2 phase is crucial in resisting dislocation motion and preventing further deformation. Additionally, the addition of silicon led to improved corrosion resistance, as demonstrated by potentiodynamic polarization measurements. However, a trade-off was observed between compressive strength and ductility: compressive strength increased with higher silicon concentrations, but at the expense of ductility.

Tuberculosis (TB) is an obstinate and infectious disease requiring a relatively longer treatment duration than other bacterial infections. The current treatment regime is prolonged and cumbersome, with adverse effects, often leading to nonadherence. The upsurge in TB's multidrug-resistant and extensively drug-resistant strains with evolved resistance to existing drugs has compounded the problems. The last two decades witnessed unprecedented progress in developing TB drugs with better efficacy and reduced toxicity. Of late, inhibitors targeting the dihydrofolate reductase (DHFR) enzyme were being explored and developed as antitubercular drugs. A plethora of diverse molecular cores, such as pteridines, diamino heterocycles, diamino triazoles, and nontraditional cores, were developed recently as Mtb- DHFR targets. Besides the characteristic binding pockets of Mtb- DHFR, an extended hydrophilic binding pocket was also studied for intermolecular interactions with the designed compounds to assess the enzyme specificity. In this study, prominent DHFR inhibitors developed in the last two decades were reported. Key features of the designed compounds, such as the structural similarities with existing pharmacophores, interactions with binding pockets, enzyme selectivity and specificity, and percentage of inhibition, were evaluated. The authors hope the study will help streamline the pharmacological pipeline of Mtb- DHFR inhibitors and bring the investigators one step closer to success.