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The present study examined the migration of elements from aluminum cooking pots to foods after the cooking process. This study investigated the impact of pot quality (manufacturer), pot type (traditional or pressure cooker), water supply (tap water/mineral water), food acidity, salt, spices, temperature, and cooking time on the migration of elements into cooked food. The cooking experiments were conducted to simulate the actual cooking conditions. Standard food simulant B, with 3% (w/v) acetic acid, was used in subsequent cooking trials to confirm the results. Three methods were employed to analyze the elements in the food: ICP-MS, EDS-SEM, and XPS. The cooking pots used in this investigation were examined using a Spectromaxx metal analyzer to characterize their chemical composition. The concentration of aluminum in cooked food samples increased significantly when using an aluminum pressure cooker. Food acidity, cooking duration, and the type of aluminum pot (traditional/pressure cookers) all affected the concentration of elements that migrated into the food. The aluminum level increased from 80.17 to 133.7 µg/g when tomato sauce was added to the food. Increasing the heating time resulted in an increased aluminum content (157.9 µg/g) in the cooked food. Aluminum pressure cookers exhibited the highest amount of aluminum migration into the food. Foods cooked in a pressure cooker made by manufacturer (3) contained the highest aluminum content (252.7 µg/g), which increased the risk of exceeding the daily intake limit of aluminum. The prepared food samples under all conditions showed a safe health profile for daily intake of all elements (Fe, As, Cd, and Pb), except for Al, which exceeded the daily intake limit when using pressure cookers for extended cooking times. The results of element migration into food simulants were consistent with those of food samples. The results confirmed that SEM-EDS and XPS techniques are not suitable for quantifying the elements that migrated into food samples due to their detection limits. [ABSTRACT FROM AUTHOR]

Correct modelling and estimation of solar cell characteristics are crucial for effective performance simulations of PV panels, necessitating the development of creative approaches to improve solar energy conversion. When handling this complex problem, traditional optimisation algorithms have significant disadvantages, including a predisposition to get trapped in certain local optima. This paper develops the Mantis Search Algorithm (MSA), which draws inspiration from the unique foraging behaviours and sexual cannibalism of praying mantises. The suggested MSA includes three stages of optimisation: prey pursuit, prey assault, and sexual cannibalism. It is created for the R.TC France PV cell and the Ultra 85-P PV panel related to Shell PowerMax for calculating PV parameters and examining six case studies utilising the one-diode model (1DM), two-diode model (1DM), and three-diode model (3DM). Its performance is assessed in contrast to recently developed optimisers of the neural network optimisation algorithm (NNA), dwarf mongoose optimisation (DMO), and zebra optimisation algorithm (ZOA). In light of the adopted MSA approach, simulation findings improve the electrical characteristics of solar power systems. The developed MSA methodology improves the 1DM, 2DM, and 3DM by 12.4%, 44.05%, and 48.88%, 28.96%, 43.19%, and 55.81%, 37.71%, 32.71%, and 60.13% relative to the DMO, NNA, and ZOA approaches, respectively. For the Ultra 85-P PV panel, the designed MSA technique achieves improvements for the 1DM, 2DM, and 3DM of 62.05%, 67.14%, and 84.25%, 49.05%, 53.57%, and 74.95%, 37.03%, 37.4%, and 59.57% compared to the DMO, NNA, and ZOA techniques, respectively. [ABSTRACT FROM AUTHOR]

To date, ECAP technique have been successfully employed to produce Ultra-fine/Nanostructure grain materials, but some materials such as hexagonal closed-packed (HCP) alloys are difficult to process by ECAP at room temperature. In this work, Transmission Electron Microscopy (TEM), Vickers hardness test and Torsion test were employed to confirm the attainment of ultrafine/nanostructured grain (UFG/NSG) commercial pure titanium (CP-Ti) Titanium fabricated by ECAP as a sever plastic deformation process. The samples were pressed by ECAP (route BC) up to four passes at elevated temperature (400° C). Finally, the Erosion-Corrosion (E-C) behavior of ultrafine/nanostructured grain (UFG/NSG) Titanium in a simulated body fluid were investigated through weight loss measurement.

In this work, the continuous hot-compaction behavior of Quinary-FeCrCuMnTi, Senary-FeCrCuMnTiV, and Septenary-FeCrCuMnTiVZn equiatomic nanostructured high-entropy alloys (HEAs) was studied from 0 to 550 MPa pressure in a universal testing machine. These alloys were synthesized by mechanical alloying and characterized by HRSEM and HRTEM. The synthesized powders were compacted at different temperatures (RT to 525°C) using a universal testing machine operated at 10 mm per minute. Microstructural results demonstrated that multiphase solid solutions were obtained in all the HEAs. Septenary-FeCrCuMnTiVZn HEA has produced a higher amount of FCC phase compared to other alloys due to the incorporation of low melting Zn atoms enhancing solid solutions leading to produce a lower value of FCC phase crystallite size (7.8 nm). The continuous hot-compaction results explained that the percentage relative density was increased drastically after 225°C due to the elimination of internal stress, and decreased dislocation density. Senary-FeCrCuMnTiV HEA exhibited a higher percentage of relative density in all operating conditions due to more crystallite size, lower value of powder particle sizes, and the domination of BCC-V atoms in addition to high-configurational entropy. The experimental relative density-pressure data were fitted linearly using the Panelli and Ambrozio Filho equation for exploring the plastic deformation ability of developed powder particles. [ABSTRACT FROM AUTHOR]

Additive manufacturing technology can help us to produce complex components/parts easily. It can be used to develop the parts with multi‐material structures consisting of thermoplastic, thermosetting plastic, and ceramic fibers. This multi‐material structure enhances the performance of lightweight polymer‐based components. In this research work, poly‐lactic acid (PLA) lattice (mono‐material structure), PLA lattice filled with epoxy (bi‐material structure), and PLA lattice incorporated with embedded milled glass fibers (MGFs) in an epoxy matrix (tri‐material structure, TMS) were designed and developed by fused filament fabrication and solution casting methods. PLA lattice of 50% volume was fixed in all structures and 50% volume was filled with epoxy and MGFs. The dispersed MGFs in epoxy matrix were varied from 0, 2.5, 5, and 7.5 vol%. The mechanical properties were carried out by compression test, three‐point bending test, and tensile test. The results revealed that 5 vol% of MGFs in the epoxy sample (TMS) exhibited improved mechanical performances compared to other samples. The cone‐beam CT scan results confirmed the voids/porous free surfaces in the developed materials. The high‐resolution scanning electron microscope microstructural evolutions in‐terms of topography and fractured regions were also examined and reported. [ABSTRACT FROM AUTHOR]

High entropy alloys (HEAs) are being attracted recently by several researchers, scientists, and academicians to achieve extraordinary and outstanding properties that cannot be obtained from conventional alloys. HEAs are multicomponent alloys in which a minimum of five metallic elements are mixed in an equal molar or non-equal molar ratio. The rapid growth of this field produces a huge amount of scientific papers over the last decade. However, still, there is a need to review various manufacturing methods and their results. Also, the outcome of the scientific articles related to HEAs has ignored the various methods of synthesizing and manufacturing. In this review article, an attempt was made and largely concentrated on the methods and techniques that can be used in the manufacturing and synthesizing of the HEAs. Recently, the properties of HEAs become much better when compared to conventional alloys. Some techniques have succeeded in producing ultrafine microstructure grains which become a leap in industrial fields. Now, the manufacturing methods of conventional alloys are almost familiar and implemented according to the suggestions given by the researchers and academicians based on their work. Therefore, the present review article has demonstrated various methods of manufacturing of HEAs with novel schematics with a preview description for more understanding of the basic work criteria. Besides, this article has reviewed the outcomes of several research articles related to several methods, then compared the outcome of each method with the corresponding mechanical properties, and major challenges of HEAs are discussed and reported. [ABSTRACT FROM AUTHOR]

In the present work, the room temperature deformation behavior of dezincification-resistant (DZR) brass was performed by varying strain rates (1 × 10−4 s−1, 0.55 × 10−3 s−1, 1 × 10−3 s−1, 0.55 × 10−2 s−1, 1 × 10−2 s−1) and percent cold works (15 to 65% with step of 10%). These parameters are important to plumbing parts of its forming. Room temperature deformation workability map was developed that provides the selection of safe deformation parameters without cracking. The as-received and deformed DZR brass samples were carefully characterized by various microscopes. The results revealed that more dislocations lines and twinning were observed through transmission electron microscope images as the strain rate (SR) increases which led to early failure of the sample before reaching the set height reduction. It was determined that more amount of strain hardening with designed height reduction was achieved at lower SR whereas less amount of strain hardening was achieved at higher SR due to strain mismatching phenomenon and various deformation mechanisms. [ABSTRACT FROM AUTHOR]

Heat recovery steam generators (HRSGs) are important components for industrial waste heat recovery, and any changes in their design directly affect the performance of the steam cycle, and thus the performance of the combined cycle power plant. The present research is focused on the design of a HRSG, including a dual-pressure steam generator cycle that is intended for use in a typical gas turbine unit having a power output of 60 MW. The results show that the maximum heat transfer occurs in the evaporator section for high-pressure levels, and in the economizer section for low-pressure levels. The optimum design pressure for the high-pressure level of the steam generator was found to be 100 bar, while that for the low-pressure level was found to be 10 bar. An exergy analysis was performed for the different processes and components of the steam cycle, including the HRSG. Calculations show that the overall exergy loss is about 35%, out of which 16% is lost in flue gasses and 10% is lost in heat exchanger, and the remainder was converted into 35 MW of useful work. [ABSTRACT FROM AUTHOR]

Titanium and its alloys are used in several industries, especially in medical and dental applications. In the present study, the surface properties of nanostructured commercially pure titanium (CP-Ti) and its erosion-corrosion (E-C) behavior in simulated body fluid were studied. Equal-channel angular pressing (ECAP) was performed at a high temperature (400 °C) to produce nanostructured grain samples of CP-Ti. Then, the effects of ECAP passes on the E-C resistance under various conditions were investigated via weight loss measurements. Optical microscopy and transmission electron microscopy observations were performed to investigate the microstructural changes of the material. The surface roughness of the CP-Ti samples was evaluated using an optical profiling system. Mathematical equations of the modified Finnie model were employed for the analytical analysis of the E-C behavior. Additionally, computational fluid dynamics was utilized to model the E-C behavior of CP-Ti. Overall, the results showed that the ECAP process improved the E-C resistance of CP-Ti. A difference of 12 pct was observed between the experimental and numerical results of E-C resistance, which is acceptable for practical applications [ABSTRACT FROM AUTHOR]

During the past few decades, ultrafine-grained materials (UFG) have experienced rapid development. Enhanced mechanical and surface properties, such as strength, ductility and erosion-corrosion (E-C) resistance by refining the grain to ultra-fine/nanometer size has been achieved. The equal channel angular pressing (ECAP) is a popular severe plastic deformation (SPD) method to fabricate UFG bulk materials. In this research, the E-C behavior of commercial annealed pure copper subject to four passes of ECAP have been investigated. Hardness measurement of the copper specimen after four passes of ECAP showed an increase of 200% on the hardness value as compared with annealed condition. Simulated seawater was used as an E-C medium. The effect of different E-C parameters such as time, slurry flow velocity, impact angle, and solid particle concentration on ECAP process is studied. The results showed that ECAP enhances the E-C resistance of copper, and this behavior improves with increasing the pass number. Generally, a 30% rise in resistance to E-C was achieved after four ECAP passes as compared to coarse grain copper for the parameters studied in this work. Optical microscopy was used to examine the microstructure and material removal mechanism of the annealed copper. Scanning electron microscopy (SEM) was used to validate the reduction of grain size due to ECAP process. Furthermore, examination of the surface roughness of the copper at different ECAP passes showed that for the same E-C condition the increment of ECAP passes leads to a smoother surface. [ABSTRACT FROM AUTHOR]

The last decade has witnessed considerable advancements in nanostructured material synthesis and property characterization. However, there still exists some deficiency in the mechanical and surface property characterization of these materials. In this paper, the erosion corrosion (E-C) behavior of nanostructured copper was studied. The nanostructured copper was produced through severe plastic deformation (SPD) by applying four passes of equal channel angular pressing (ECAP). The combined effects of the testing time, impact velocity, and concentration of erosive solid particles (i.e., sand concentration) on the E-C behavior of nanostructured copper were then examined. Based on a defined domain for the testing time, impact velocity, and sand concentration, E-C tests were performed for numerous combinations of test points via the slurry pot method. The test points were selected using the face-centered center composite design of experiments to enable visualization of the test results through surface plots. The extent of E-C on the test specimens was determined by measuring the mass loss. Polynomial regression and Kriging were used to fit surfaces to the experimental data, which were subsequently used to generate surface plots. The results showed that the E-C of nanostructured copper is best described by a quadratic function of testing time, velocity, and erosive solid particle concentration. The results also revealed that E-C increases with an increasing testing time, impact velocity, and erosive solid particle concentration. In addition, it was observed that the effect of the erosive solid particles on E-C is further intensified by an increased impact velocity. [ABSTRACT FROM AUTHOR]

Quality of machined surfaces and its integrity are strongly dependent on tool wear, which consequently depends on the tool life or machining time. Therefore, prediction of the machining time of the cutting tool during machining processes is very important in order to obtain high precision parts and to reduce manual fit operations and production cost. In this work, the relationship between texture features of the gray-level co-occurrence matrix and the machining time of the cutting tool in turning operations has been investigated, and the results show that four texture features are highly correlated with machining time. These highly correlated texture features were utilized to calculate machining time of the cutting tool from captured images of machined parts. The verification results showed that the maximum percentage of error between the actual and calculated machining time ranged between −4.65% and 7.79%. [ABSTRACT FROM PUBLISHER]

The densification behavior of FeCrCuMnTi (HEA1), FeCrCuMnTiV (HEA2), and FeCrCuMnTiVZn (HEA3) equiatomic high-entropy alloys (HEAs) was explored using different uniaxial quasi-static controlled compaction (1 mm/min). These HEAs were synthesized by mechanical alloying (MA, speed: 300 rpm, BPR: 10:1, time: 25 h). Various phase formations, structural characteristics (crystallite size, lattice strain, and lattice constant), thermo-dynamic calculations, powder surface morphologies, detailed microstructural evolutions, and chemical compositions were examined using X-ray diffraction, high-resolution scanning electron microscopy, and high-resolution transmission electron microscopy. The XRD results revealed the formation of multiple solid solutions (FCC, BCC, and HCP) due to the variation in entropy, and the presence of high-strength elements (Cr, Ti, and V) in the developed HEA alloys. The synthesized powders were consolidated into bulk green samples with different compaction pressures starting from 25 to 1100 MPa under as-milled and milled under stress recovery conditions (150 °C, 1 h). The incorporation of V in the FeCrCuMnTi HEA resulted in improved densification due to a greater reduction in particle size, and high configurational entropy. Furthermore, the stress-recovered powder samples produced more relative density owing to the elimination of lattice strain. Several linear and non-linear compaction models were applied to predict densification behavior. The non-linear Cooper and Eaton model produced the highest regression coefficients compared to the other models. [ABSTRACT FROM AUTHOR]

This paper describes the use of an elastic nanocomposite sensor to measure the water flow rate in open and closed hydraulic circuits. A sensor was constructed of multiwalled carbon nanotubes (MWCNTs) dispersed in silicone rubber (SR) and subsequently tested to verify its ability to measure water flow rate. The results reveal that the correlation between the fluid flow rate and the pressure variation across the sensor entails that its electrical resistance can be correlated to the flow rate. The sensor constructed of 2 and 3 wt,% of MWCNTs in SR-based nanocomposite sensors exhibited a low percolation threshold. An electron microscope (HRSEM) was used to characterize the manufactured nanocomposite sensors and confirm the conductive networks. The variation in the electrical resistance of the sensor in terms of both water pressure and flow rate is described. The elastic sensor was calibrated to measure the water flow rate in the range of 0–35 l/min. The results show that an elastic sensor fabricated from MWCNTs dispersed in silicone rubber does exhibit sensitivity to the slight strain levels produced by dynamic water pressure and, as such, can be used to measure flow rate. In addition, the sensor's response to water flow in the presence of bubbles enables pump cavitation monitoring. This paper also investigates the reduction of sensor electrical conductivity in response to water immersion. The findings reveal that the elastic nanocomposite sensor could potentially be used as a liquid sensor to detect water leakage in hydraulic circuits. • An elastic sensor is developed to measure water flow rates in hydraulic circuits. • The sensor can measure turbulent water flow rates in the range of 2–35 l/min. • The sensor can provide a reasonable sensitivity of 0.076–0.9 kΩ/l/min. [ABSTRACT FROM AUTHOR]

Multiaxial forging (MAF) is one of the appealing methods of severe plastic deformation (SPD) techniques to fabricate ultrafine-grained (UFG) materials. In this study; the influence of process parameters such as strain rate; friction; and initial temperature has been assessed through finite element simulation of Nickel 200 alloy. The Johnson–Cook equation was applied in simulating the MAF process. The homogeneous microstructure of a material processed by MAF is an important requirement to obtain uniform mechanical and other properties. The uniformity in properties was evaluated by the investigation of the hardness measurements; effective strain (ES), and inhomogeneous factor (IF) or coefficient of standard deviation. The results showed that the inhomogeneous factor decreases with an increase in strain rate and decrease in temperature. It was found that a more homogeneous structure is observed with an increasing number of MAF cycles and the strain rate strain. Furthermore; the average grain size reduced from 850 nm to 220 nm after three cycles of MAF. Finally; experimental work was performed to validate the results. [ABSTRACT FROM AUTHOR]

• Synthesized Nanocrystallite Entropy Alloys. • Examined the structural properties and characterizations effectively. • Extensive mechanical properties were achieved. • Studied the various strengthening mechanisms. The present research work has concentrated to synthesize nanocrystalline (NC) Cr 0.26 Fe 0.24 Al 0.5 (medium entropy alloy, 3E-MEA) and Cr 0.15 Fe 0.14 Al 0.30 Cu 0.13 Si 0.28 (high-entropy alloy, 5E-HEA) non-equiatomic (equal weight fraction) alloys through mechanical alloying (MA); which studied the influence of entropy effect on structural properties, microstructural characterization, and mechanical behaviour. Further, the same non-equiatomic ratio of two coarse grain alloys (CGAs) was manufactured by conventional powder metallurgy (PM) route (blending method, 3E-CGA, 5E-CGA) for comparison. All synthesized powders were hot-pressed (HPed) at 723 k for 30 min subsequently mechanical properties in terms of compressive stress-strain and hardness were examined. The samples of as-milled powders, HPed, and fractured were investigated using X-ray diffraction (XRD) and advanced electron microscopes. The HPed sample of 3E-MEA of Cr 0.26 Fe 0.24 Al 0.5 produced 94% BCC and 6% FCC crystal structures due to more dissolution of Al atoms in the stronger bonding atoms of Cr-Fe lattice. Whereas 5E-HEA of Cr 0.15 Fe 0.14 Al 0.30 Cu 0.13 Si 0.28 sample has exhibited 72.1% FCC phase and 27.9% BCC phase due to balance between the dissolution of FCC elements (Al, Cu, Si) and BCC elements (Cr, Fe). Further, 3E-MEA and 5E-HEA have exhibited the ultimate compressive strength (UCS) of 1278 ± 6.75 MPa and 2060 ± 2.8 MPa respectively whereas the corresponding conventionally blended alloys produced 268 ± 5 MPa and 615 ± 3 MPa for 3E-CGA and 6E-CGA respectively. Vicker's hardness strength (VHS) of 5E-HEA of Cr 0.15 Fe 0.14 Al 0.30 Cu 0.13 Si 0.28 has exhibited 68% more when compared to 3E-MEA of Cr 0.26 Fe 0.24 Al 0.5 , 3.26 times higher compared to blended alloys. Further, several strengthening mechanisms on the mechanical behaviour of MEA and HEA were investigated in which dislocation strengthening mechanisms followed by solid solution strengthening mechanisms have influenced more as compared to grain boundary strengthening mechanisms. [ABSTRACT FROM AUTHOR]

• Synthesis of Al 0.3 CrFeNiCo 0.3 Si 0.4 nanocrystalline HEA using mechanical alloying. • Microstructural analysis of the HEAs with XRD, SEM, EDS, and TEM techniques. • Laser particle size analysis of the processed HEAs powders. • Investigation of the compaction behaviour of the developed HEAs. This research article focused on developing Al 0.3 CrFeNiCo 0.3 Si 0.4 nanocrystalline high-entropy alloy (HEA) by mechanical alloying. The initial powders mixture was ball milled for 1 hr (HEA-1 h), 5 hr (HEA-5 h), 15 hr (HEA-15 h) and 25 hr (HEA-25 h) at ball to powder mass ratio (BPR) of 15:1 and a speed of 300 rpm. The mechanical alloying time was varied from 1 to 25 hr to ensure the nanocrystalline nature and attainment of steady state in HEA powders. The structure of the developed HEAs was characterized by means of X-ray diffraction (XRD), Laser particle size analyzer (LPSA), and various electron microscopes (TEM and FEGSEM with EDS). HEA-25hr sample exhibited the crystallite size of 13.8 nm with lattice strain of 0.67% obtained from XRD which matched the result by TEM. The formation of a solid solution (SS) with a uniform elemental dispersion was observed with a major BCC stable structure and a minor FCC structure in HEA-25 h sample. The HEA-25 h sample revealed an average particle size of 386.2 nm (89.8% peak intensity) with Polydispersity Index (PDI) value of 0.364 which confirmed the uniform distribution of particles over a narrow range of particle size. The synthesized powders were consolidated to green compacts with a loading rate of 1 mm/min at different compaction pressures (25, 50, 75, 100, 150, 200, 400, 600, 800, 1000, and 1100 MPa) for examining the powder particles packing. Several compaction models (both linear and non-linear) were discussed to establish the density-pressure relationship of developed HEAs. The results revealed that the milling time has influenced the relative density. HEA-1 h sample was exhibited the relative density of 0.76 whereas HEA-25 h sample was produced the relative density of 0.6 indicating more strength and more amount of strain hardening occurs in MAed HEA-25 sample in addition to the entropy effect for the same composition. [ABSTRACT FROM AUTHOR]

This research article has concentrated to develop a novel silicon brass of [82Cu4Si14Zn] 100-x – x wt.% B 4 C (x = 0, 3, 6, 9, and 12) nanocomposites which were synthesized by mechanical alloying followed by vacuum hot pressing for consolidation of powders into bulk samples. Single vial planetary ball mill was used to synthesize the nanocomposite powders in which the ball-to-powder ratio of 10:1 with the milling time of 20 h was used. The milled powders were compacted and sintered simultaneously using vacuum hot pressing equipment for 1 h at 900 °C. The structural, mechanical and tribological properties were characterized and investigated by x-ray line profile analysis (XRD), scanning electron microscopy (SEM), electron backscattered diffraction images (EBSD), energy dispersive x-ray spectroscopy (EDS), Vickers microhardness, compression test, and dry sliding wear behaviour analysis. It has been found that B 4 C nanoparticles had homogeneously distributed and embedded in the nanocrystallite matrix. As a result, the fabricated nanocomposites were exhibited superior properties than the conventional alloy. Here, 12 wt% B 4 C reinforced silicon brass of bulk nanocomposite was produced higher hardness and compressive strength than the unreinforcement matrix. Further, the worn morphologies were evidenced the mild wear occurred at higher reinforced nanocomposites owing to decohesion and lower wear rate with considerable wear resistance. [ABSTRACT FROM AUTHOR]