Addition Of Aluminum Research Articles

Синтез и свойства каталитических хемосорбентов на основе оксида титана

In this work, we studied the synthesis and properties of catalytic chemisorbents based on titanium dioxide with additions of ZnO and γ-Al2O3. The goal was to obtain chemisorbents with desired performance characteristics and evaluate their potential in destructive hydrogenation of organo-sulfur compounds. Their sulfur capacity and hydrogenating capacity were measured by the static method with carbon disulfide absorption. Textural and morphological characteristics were deter-mined with the use of X-ray phase analysis, low-temperature nitrogen adsorption/desorption, and scanning electron microscopy. It was also found that addition of alumina did not give additional reflections on the X-ray pattern, in contrast to introduction of zinc oxide. It was found that addi-tion of zinc oxide significantly increased the values of the specific surface area, many times more than expected, according to additivity principle. Conversely, addition of alumina did not give the expected increase in surface area. The one and the other were explained through active interaction of phases. The ratios of components for obtaining chemisorbents with optimal strength properties were established. It was found that a composite consisting of titanium and aluminum oxides was more resistant to sulfurization than one with additions of zinc oxide. SEM and low-temperature ni-trogen adsorption/desorption methods confirmed the mesoporous structure of the studied samples, while the sample containing gamma alumina showed a more pronounced desorption branch to-gether with the surface consisting of spherical formations arranged in a regular order. The sample with zinc oxide had slit-like pores in its volume. Hydrogenation of thiophene with gaseous hydro-gen was carried out for the studied composites. Chromatographic analysis of the resulting product was performed. It was proven that composites based on titanium, zinc, and aluminum oxides not only had sorption properties with respect to organosulfur compounds, but also catalyzed their de-structive hydrogenation. Thus, it was established that the studied samples were chemisorbents. The study provides insight into synthesis and properties of catalytic titania-based chemisorbents, high-lighting the influence of additives and their potential for organosulfur reduction reactions.

НИЗКОЦЕМЕНТНЫЙ ОГНЕУПОРНЫЙ БЕТОН НА ОСНОВЕ ЗАПОЛНИТЕЛЯ ИЗ КАОЛИНОВОГО ШАМОТА С УЛУЧШЕННЫМИ ПОКАЗАТЕЛЯМИ УДОБОУКЛАДЫВАЕМОСТИ

The paper presents the results of developing low-cement fireclay concrete based on kaolin chamotte. As a result, concrete with the highest application temperature of up to 1500 °C was obtained. The use of narrow fractions of chamotte with low (less than 5%) water demand ensures the production of low-cement concrete with high rates of mobility of the concrete mixture. The research focused on the influence of the additions of sodium tripolyphosphate, reactive alumina and superplasticizers based on naphthalene and polycarboxylate on the spreadability of the concrete mixture and the basic heat-resistant properties of concrete. The use of sodium tripolyphosphate most contributes to the sintering processes of cement stone in concrete. The developed heat-resistant concrete is haracterized by high compressive strength (more than 50 MPa after the first heating to operating temperatures) and heat resistance (at least 20 water heat cycles).

Effects of rattan fiber length variation on mechanical properties, characterization, and microstructure of concrete

The study aimed to test how variations in fiber length affect the behavior of microstructures in concrete, as well as to characterize and analyze their mechanical properties. This research covers several specific objectives, including understanding the influence of different fiber lengths on micro and macrostructural aspects of concrete, assessing the mechanical properties of reinforced concrete with fibers of various lengths, and examining the relationship between fiber length and the mechanical performance of concrete. The results showed that the addition of rattan fibers in concrete can increase or even reduce tensile strength depending on the length of the fibers and their material characteristics. The addition of rattan fibers with a length of 30 mm results in a significant increase in tensile strength, while longer or shorter fiber lengths do not yield equally favorable results. Analysis of the chemical composition of concrete shows that the elements oxygen (O), calcium (Ca), and silicon (Si) predominate, with the addition of carbon (C), iron (Fe), aluminum (Al), magnesium (Mg), and Sulphur (S) elements in concrete with rattan fibers. Morphological observations using SEM on concrete, both with fibers and without fibers, provide an in-depth understanding of the structure of concrete surfaces microscopically

Porous MgO-based ceramics synthesized by the volume expansion effect: Designing and performance

High-quality porous ceramics are extremely attractive in terms of energy conservation and consumption reduction, and thus are one of the research hotspots pursued in recent years. For this purpose, porous MgO-based ceramics with outstanding thermal shock resistance and thermal insulation performance were designed and prepared by using the direct firing method and introducing alumina with different paticle sizes as additives. The results reveal that the in-situ formed MgAl2O4 phase by alumina additives simultaneously improves the apparent porosity, thermal insulation, and thermal shock resistance of the prepared MgO-based ceramics. Specifically, the increase in the apparent porosity can be attributed to the volume expansion effect of MgAl2O4 phase, so the industrial alumina with larger particle size is more effective (20 wt% addition: the apparent porosity from 43.5 % to 55.4 %, the thermal conductivity from 0.977 to 0.389 W m−1 K−1 at 800 °C); moreover, the enhancement in thermal shock resistance can be ascribed to the residual stress effect caused by the MgAl2O4 particles, so the micron alumina with smaller particle size is more efficient (10 wt% addition: the residual strength ratio from 93.48 % to 65.13 %–113.92 % and 94.47 % after one and five air-quenching). Therefore, this work demonstrates a novel synthetic strategy for porous ceramics with great potential in the field of high-temperature thermal insulation.

Dependence of the structural and rheological characteristics of vibrocasting alumina­chromia castable and the properties of samples from it on the active alumina additive

The influence of additives amount (1—5 %) of two dispersed a­form active alumina with practically the same chemical composition but with different dispersion (specific surface area of 3.0 and 5.0 m2/g) on the moisture content of vibrocasting coarse­grained low­cement alumina­chromia castable mass (masses without the mentioned additives and with 1—5 % additive), on the strength of its structure 30, 60 and 90 minutes after the mass preparation and the effect on main properties of vibrocast castable samples from it (masses with an addition of 5 % of the mentioned alumina) both the unfired (cold crushing strength after hardening in humid conditions for 1; 3; 7 days) and fired at a temperature of 1580 °C ones (open porosity, apparent density, cold crushing strength) was studied. It was established that an increase in the amount of both active alumina and an increase in their dispersion leads to a gradual natural tendency to reduce the moisture content of masses while improving their flowing compared to the mass without the addition of dispersed active alumina; obtaining high strength of the mass structure, and higher with the addition of more dispersed alumina; improving the properties of unfired castable compared to castable without the addition of dispersed active alumina. More dispersed alumina was more effective both in reducing the moisture content of castable and improving its properties. The practicality of introducing dispersed active alumina of one of the studied grades into castable was shown.
 Based on the research results, an improved technology for manufacturing by vibrocasting castable products from low­cement alumina­chromia castable mass containing an active alumina additive was developed. This technology ensures the production of unfired and fired products with improved properties. The technical documentation was developed and the raw material base for the production of low­cement alumina­chromia castable was expanded.

Elastomer Composites with High Damping and Low Thermal Resistance via Hierarchical Interactions and Regulating Filler.

Modern microelectronics and emerging technologies such as wearable electronics and soft robotics require elastomers to integrate high damping with low thermal resistance to avoid damage caused by vibrations and heat accumulation. However, the strong coupling between storage modulus and loss factor makes it generally challenging to simultaneously increase both thermal conductance and damping. Here, a strategy of introducing hierarchical interaction and regulating fillers in polybutadiene/spherical aluminum elastomer composites is reported to simultaneously achieve extraordinary damping ability of tan δ>1.0 and low thermal resistance of 0.15cm2 KW-1 , which surpasses state-of-the-art elastomers and their composites. The enhanced damping is attributed to increased energy dissipation via introducing the hierarchical hydrogen bond interactions in polybutadiene networks and the addition of spherical aluminum, which also functions as a thermally conductive filler to achieve low thermal resistance. As a proof of concept, the polybutadiene/spherical aluminum elastomer composites are used as thermal interface materials, showing effective heat dissipation for electronic devices in vibration scenarios. The combination of outstanding damping performance and extraordinary heat dissipation ability of the elastomer composites may create new opportunities for their applications in electronics.

Efficient Sodium-Ion Storage Using MoS2@rGO Nanocomposite Anode: Exploring Na-Ion Diffusion in Metallic Phase

Sodium-ion batteries (SIBs) are gaining attention as a better and more economical option than lithium-ion batteries, owing to the abundance and low cost of sodium in comparison to lithium. The anode component of rechargeable batteries plays a vital role in obtaining superior energy and power density. Consequently, the investigation of novel materials for SIBs with enhanced performance is imperative. Transition metal chalcogenides (TMDs) are found to be promising contenders for this purpose, particularly MoS2 due to their two-dimensional open framework, structural tunability, and high theoretical specific capacity as an anode material in sodium ion storage. In this regard, we conducted a facile strategy to synthesize MoS2 and aluminium-doped MoS2 incorporated into reduced graphene oxide (rGO) using the hydrothermal method. The structural and morphological properties of the samples have been explored through X-ray diffraction (XRD), Raman spectroscopy, field-emission scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM) measurements which revealed that the addition of aluminium increased the interlayer spacing of the (002) plane of MoS2 nanosheets and stabilized it in metallic 1T phase. The enhanced interlayer distance and improved conductivity of the electrode material displayed a significantly higher initial discharge specific capacity of around 750 mAhg−1 which is stabilized around 380 mAhg−1 at the current rate of 50 mAg−1 after 10 cycles as investigated through galvanostatic charge-discharge measurement. The long cycling test for 200 cycles revealed the capacity retention of ~65% and ~55 % at the current density of 100 and 300 mAg-1, respectively. The kinetic behavior of the Na-ion is studied employing cyclic voltammetry (CV), galvanostatic intermittent titration technique (GITT), and electrochemical impedance spectroscopy (EIS), and the diffusion coefficient of Na-ion in the bulk of the electrode was found to be in the range of 10-10 to 10-12 cm2s-1. Additionally, in-situ EIS analysis demonstrates the electrode's electrochemical kinetics at different charge-discharge states by showing variations in charge transfer resistance. Ex-situ XRD and X-ray photoemission spectroscopy (XPS) demonstrated the coexistence of 1T and 2H phases, and field-emission SEM validated the stable morphology after cycling. Keywords: Sodium-ion batteries, Transition metal chalcogenides (TMDs), Anode material, MoS2

Effects of alumina addition on electrical properties of alumina-toughened zirconia for application in low- and intermediate-temperature solid oxide fuel cells

One of the priorities in the field of hydrogen energy is the development of intermediate-temperature (IT-SOFCs) and low-temperature solid oxide fuel cells (LT-SOFCs), which are capable of highly efficient operation in the range of 500–800 °C. The currently applied 8-YSZ electrolytes are expected to be replaced by one based on tetragonal zirconia (3Y-TZP), which is characterized not only by high ionic conductivity below 700 °C, but also significantly higher mechanical strength. One of the candidates is alumina-toughened zirconia (ATZ) with extraordinary mechanical properties (flexural strength of up to 1 GPa and outstanding fracture toughness (KIc) in excess of 10 MPa m0.5). A series of composites with a nanometric alumina content of 2.3, 10, and 20 vol% were obtained and investigated to evaluate the effects of aluminum addition on the electrical properties of the materials in relation to their microstructure, chemical and phase composition. Measurements performed by means of electrochemical impedance spectroscopy over the range of 300–650 °C showed that the total electrical conductivity of the obtained ATZ samples decreased slightly with increasing content of alumina inclusions and it was around one-third of an order of magnitude lower than that of the reference 3Y-TZP sinter prepared from the commercially available oxide powder containing 3 mol% of yttrium oxide (TOSOH). This is a consequence of the fact that ATZ sinters exhibited a lower specific conductivity of grain boundaries than 3Y-TZP whilst having comparable electrical conductivity of grain interiors. The total electrical conductivity values determined for the ATZ sinters at 700 and 800 °C are approximately the same as the electrical conductivity of 3Y-TZP, and they can therefore be considered a viable alternative to 8-YSZ electrolytes in applications such as IT-SOFCs or LT-SOFCs.

Understanding Electrochemical Performance Enhancement with Quaternary NCMA Cathode Materials.

Ni-rich cathode materials show promise for use in lithium-ion batteries. However, a significant obstacle to their widespread adoption is the structural damage caused by microcracks. This research paper presents the synthesis of Ni-rich cathode materials, including LiNi0.8Co0.1Mn0.1O2 (referred to as NCM) and Li(Ni0.8Co0.1Mn0.1)0.98Al0.02O2 (referred to as NCMA), achieved through the high-temperature solid-phase method. Electrochemical (EC) testing results reveal the impressive EC performance of NCMA. NCMA exhibited a discharge capacity of 141.6 mAh g-1 and maintained a cycle retention rate of up to 74.92% after 300 cycles at a 1 C rate. In contrast, the NCM had a discharge capacity of 109.7 mAh g-1 and a cycle retention rate of 61.22%. Atomic force microscopy showed that the Derjaguin-Muller-Toporov (DMT) modulus value of NCMA exceeded that of NCM, signifying a greater mechanical strength of NCMA. Density functional theory calculations demonstrated that the addition of aluminum during the delithiation process led to the mitigation of anisotropic lattice changes and the stabilization of the NCMA structure. This improvement was attributed to the relatively stronger Al-O bonds compared to the Ni(Co, Mn)-O bonds, which reduced the formation of microcracks by enhancing NCMA's mechanical strength.

Aluminum addition to Sn-3Ag-0.5Cu-1In-xAl alloy effect on corrosion kinetics in HCl acid solution

This study examines how adding aluminum to the SAC205-1In-xAl solder alloys in a 1 M hydrochloride acid HCl solution affects their corrosion behavior. HCL acid has a faster corrosion rate than other electrolytes because it contains chlorine (Cl−) and hydrogen (H+) ions. In contrast to other electrolytes like salt and alkaline solutions, which only have one type of ion species for causing corrosion, The characteristics of the produced solder alloy samples were investigated using SEM and EDX tests. Corrosion potentials were shown by polarization investigations, adding 0.3, 0.5, 0.7, 0.8, and 0.9 wt% Al to the SAC205-1In solder alloy. Based on polarization analyses, the produced solder alloys exhibit slightly different corrosion potentials when Al is added in comparison to the corrosion potentials of SAC305 and SAC205-1In. Corrosion rates exhibit a pattern whereby adding 0.8 wt% Al reduces the corrosion rate. However, as less aluminum is replaced with tin, the corrosion rate slightly increases. SAC205-1In's corrosion rates were enhanced by the addition of Al.

Improving abrasion resistance of low temperature enamel (LTE) coating by alumina addition

Low temperature enamel (LTE) coating has advantages in material durability, hardness, corrosion resistance, and high-temperature tolerance, but shows unsatisfying abrasion resistance due to its brittle nature. Here, alumina was added to the LTE coating with contents of 0, 5, and 10 wt%. The thermal stability of alumina in the LTE matrix and the microstructure, phase composition, microhardness, impact resistance, adhesion strength, abrasion resistance, and corrosion protection properties of different LTE coatings were investigated. Results indicated that alumina had high thermal and chemical stabilities in the LTE matrix without affecting the pore structure of the coating. As an abrasion-resistant filler, alumina increased the hardness and impact resistance of LTE coatings while reducing adhesion strength. In the abrasion test, alumina showed an advantage in delaying the formation and expansion of cracks, and the alumina-enhanced LTE coating demonstrated a 70 % reduction in mass and thickness losses when compared to pure LTE coating. In particular, all LTE coatings survived 8000 cycles of abrasion without significant degradation in corrosion protection. The findings of this study confirmed the feasibility of alumina as an abrasion-resistant filler and provided a modified LTE coating for coupled corrosion and abrasion conditions.

Effect of Heat and Mass Transfer over Mixed Convective Hybrid Nanofluids past an Exponentially Stretching Sheet

The presented study investigates the heat and mass transfer characteristics of hybrid nanofluid flow past an exponentially enlarging sheet, featuring both heat source and sink effects. A distinctive aspect of this work lies in its examination of slip conditions to understand the flow behavior of hybrid nanofluids. The nanofluid itself consists of a blend of copper (Cu) and metal oxide (Al2O3) nanoparticles suspended in blood, which serves as the base fluid. This choice of nanofluid composition is noteworthy due to its potential impact on enhancing heat and mass transfer processes. Similarity conversion technique is applied that effectively transforms the partial differential equations (PDEs) governing the system into a set of ordinary differential equations (ODEs). The utilization of tables and graphs aids in conveying the influence of various embedded parameters on the obtained results. This graphical representation of parameter effects is a distinctive feature of the study, facilitating a clearer understanding of the relationships between different variables. In the concluding remarks, the study's outcomes highlight several distinctive findings. Firstly, an increase in the heat-generating parameter leads to elevated temperature distribution along the expanding sheet. Secondly, the introduction of a magnetic parameter is found to dampen the velocity of the nanofluids, which presents an interesting avenue for exploration in terms of flow control. Thirdly, the concentration profile of the nanofluids experiences a decline as the Schmidt number, a dimensionless quantity representing the ratio of momentum diffusivity to mass diffusivity, increases. It concluded that the heat and mass transfer rate is greatly enhanced by the addition of copper and aluminium oxide. This observation is a unique contribution to the understanding of heat and mass transfer behavior in such systems. The significance of this research extends to various applications, particularly in the realms of chemical engineering, environmental remediation processes, and solar thermal systems.

Innovative Transformation and Valorisation of Red Mill Scale Waste into Ferroalloys: Carbothermic Reduction in the Presence of Alumina

Primary and secondary mill scales (MSs) are waste products produced by the surface oxidation of steel during the hot (800 to 1200 °C) rolling process in downstream steelmaking. While the primary MS is comprised of FeO, Fe3O4, and Fe2O3 in a range of proportions, the secondary MS primarily contain red ferric oxide (Fe2O3) (red MS). We report a novel route for extracting iron from red MS and transforming it into ferro-aluminium alloys using carbothermic reduction in the presence of alumina. The red MS powder was blended with high-purity alumina (Al2O3) and synthetic graphite (C) in a range of proportions. The carbothermic reduction of red MS-Al2O3-C blends was carried out at 1450 °C and 1550 °C under an argon atmosphere for 30 min and then furnace-cooled. The red MS was completely reduced to iron at these temperatures with reduced iron distributed around the matrix as small droplets. However, the addition of alumina unexpectedly resulted in a significant increase in the number and sizes of iron droplets generated, much higher reactivity, and the formation of ferrous alloys. A small amount of alumina reduction into metallic aluminium was also observed at 1450 °C. There is an urgent need to identify the true potential of industrial waste and the materials within it. This study showed that red MS is a valuable material source that could be transformed into ferro-aluminium alloys. These alloys find application in a range of industrial sectors such as construction, automotive, infrastructure, etc.

Effects of nanoadditives on the performance and emissions of rapeseed biodiesel in an insulated piston diesel engine.

Energy consumption and management have emerged as crucial production functions because of the high cost of energy. Since the total consumption of fossil fuels like diesel has increased proportionally to the expansion in demand for power generation, industry, and transportation services, researchers have long been interested in constructing a more energy-efficient engine. With its improved efficiency, reduced fuel consumption, and fewer emissions, the application of nano-coating technology to engine components has become more popular in recent years. This study involved the application of a thermal barrier coating (TBC) using zirconia on the test engine piston. The aim of this research is to examine the impact of aluminium oxide nano-additives in rapeseed biodiesel blends on the performance of a diesel engine with a thermal barrier-coated piston. The four test fuels were prepared using 20% and 40% blends of rapeseed biodiesel with and without the addition of aluminium oxide at 25 ppm and 50 ppm. The full factorial design methodology was employed to examine the influential factors, specifically the rapeseed blend ratio and aluminium oxide concentration, in order to enhance performance and reduce emissions. The blends of RSB20AO25 and RSB20AO50 showed significant results on energy consumption and emissions. The RSB20AO50 blend performed with a 5.4% increase in brake thermal efficiency and a 6.5% reduction in fuel consumption compared with standard diesel. Similarly, blends of RSB20AO25 and RSB20AO50 show 6% and 11% reductions in carbon monoxide and 5.2% and 9.5% reductions in hydrocarbon emissions.

Effects of aluminum oxide addition on the surface roughness and hardness of acrylic resin denture base

Problem: Acrylic dentures frequently fracture during service due to their poor strength characteristic. Several attempts have been carried out to improve strength of acrylic by addition some materials such as fibers or Aluminum oxide. The purpose of this study was to evaluate the effect of adding Aluminum oxide (AL2O3) on the surface roughness and hardness of heat cure acrylic resin denture base material.Materials and Methods: 60 specimens were made from the heat cure acrylic resin denture base after being cured in microwave oven, 30 specimens prepared for surface roughness test and these where subdivided according to concentration of AL2O3 into three subgroups as follow:Group (A): 10 specimens of acrylic resin without AL2O3 (control group)Group (B): 10 specimens of acrylic resin+2.5% by weight AL2O3Group (C): 10 specimens of acrylic resin +5% by weight AL2O330 specimens prepared for surface hardness test and these where subdivided according to concentration of AL2O3 into three subgroups as follow:Group (A): 10 specimens of acrylic resin without AL2O3 (control group)Group (B): 10 specimens of acrylic resin+2.5% by weight AL2O3Group (C): 10 specimens of acrylic resin +5% by weight AL2O3The average of the surface roughness of the samples has been determined with using the profilometer (surface roughness tester)¸ also the average of the surface hardness of the samples has been determined with using surface hardness tester (digital micro Vickers).Result: The results showed that there were no statistically significant differences in the surface roughness and hardness.Conclusion: The addition of aluminum oxide in low percentage not affected on the surface roughness and hardness of heat cure acrylic resin.

Numerical Investigation of Thermal Behavior of Nano-Phase Change Materials Due to Non-Newtonian Fluid Flow in the Porous Finned Tube

In this study, the melting of different types of phase change materials in a heat exchanger, the effect of porosity, triangular fins, and the addition of aluminum oxide, titanium oxide, and copper oxide, nanoparticles on the thermal behavior of four types of materials are studied numerically. The enthalpy porosity method is used during the melting process. The main heat transfer fluid is non-Newtonian and the tube is filled with a porous medium. The nanoparticle volume fraction is varied from 0 to 10%, the fin height is considered from 0 to 6 mm, and the porosity is considered equal to 0.8991, 0.9138, 0.9486, and 1. Based on the results, RT26 has the lowest melting time, and RT35 has the longest melting time with an increasing percentage of approximately 250%. The addition of fins and nanoparticles leads to an increase in the liquid fraction. The full charge time of materials with the addition of aluminum oxide nanoparticles is slightly less than other nanoparticles. Furthermore, the effect of using fins is greater than the effect of the addition of nanoparticles to reduce the melting time. Also, the maximum increase in the liquid fraction is approximately 30% due to the absence of a porous medium.

Comparative Study of Quench and Partition Processes in High Si and High Al Steels

The quench and partition process is a means to develop third-generation high-strength steels using many possible process variants. In this work, two variants of quench and partitioning heat treatments, one-step and two-step, were carried out for high Si and high Al steel alloys. The kinetics of isothermal transformation occurring during the one-step quench and partition process were analysed using dilatometry. Experimental analysis revealed the swing-back phenomenon in high Si steel, and the transformation characteristics above and below the Ms temperature differed. The high Al alloy resulted in higher retained austenite (19%) compared to high Si steel (17%) during the one-step quench and partition process. Aluminium addition favoured bainite formation more than silicon addition. A comparison of two heat treatment variants shows the two-step quench and partition heat treatment seemed preferable as it produced more retained austenite (22%) in the high Si steel.

The Effect of Adding Aluminium on the Performance of ZnO NRs/PANi in Their Application as Photoelectrochemical Water Splitting

Photoelectrochemical (PEC) is a new renewable energy technology that converts H2O into hydrogen and oxygen gas with the help of sunlight. A photoelectrochemical cell device consists of three main components, one of which is the photoanode. One of the materials that can be used as a photoanode is ZnO which has good electrical properties and is non-toxic. Nanorods-structured ZnO has the advantage of being able to increase light absorption due to its high surface area. However, the resulting performance is still quite low. So it is necessary to make modifications to the photoanode, one of which is by adding aluminium material to ZnO NRs, which has the potential to increase the conductivity of PEC in the production of H2 and O2 in H2O. To overcome the loss of samples during testing, the thin film will be coated with conductive polymers such as polyaniline (PANi), which has high conductivity, can increase photoactive ability, and has good corrosion resistance. In this study, the performance of ZnO NRs/PANi against AZO NRs/PANi will be studied by adding aluminium. The ZnO nanorods were synthesized by Hydrothermal method, Aluminium was deposited on ZnO NRs by DC Magnetron Sputtering method, and PANi was synthesized by polymerization method. From the XRD characterization results, it can be concluded that the addition of aluminium to ZnO NRs/PANi causes an increase in crystallinity and peak shift. SEM characterization shows that the addition of Al to ZnO NRs/PANi causes the porosity value to increase. In addition, UV-Vis characterization showed that the addition of Al material to the ZnO NRs/PANi thin film resulted in a wider range of absorbance of the light spectrum. Then, Cyclic Voltammetry test shows that the addition of aluminium increases the efficiency of the photoelectrochemical.

Control of the Composition and Morphology of Non-Metallic Inclusions in Superduplex Stainless Steel

Duplex stainless steel is a unique material for cast products, the use of which is possible in various fields. With the same chemical composition, melting, casting and heat treatment technology, pitting and crevice corrosion were observed at the interphase boundaries of non-metallic inclusions and the steel matrix. To increase the cleanliness of steel, it is necessary to carefully select the technology for deoxidizing with titanium or aluminum, as the most common deoxidizers, and the technology for modifying with rare earth metals. In this work, a comprehensive analysis of the thermodynamic data in the literature on the behavior of oxides and sulfides in this highly alloyed system under consideration was performed. Based on this analysis, a thermodynamic model was developed to describe their behavior in liquid and solidified duplex stainless steels. The critical concentrations at which the existence of certain phases is possible during the deoxidation of DSS with titanium, aluminum and modification by rare earth metals, including the simultaneous contribution of lanthanum and cerium, was determined. Experimental ingots were produced, the cleanliness of experimental steels was assessed, and the key metric parameters of non-metallic inclusions were described. In steels deoxidized using titanium, clusters of inclusions with a diameter of 84 microns with a volume fraction of 0.066% were formed, the volume fraction of which was decreased to 0.01% with the subsequent addition of aluminum. The clusters completely disappeared when REMs were added. The reason for this behavior of inclusions was interpreted using thermodynamic modeling and explained by the difference in temperature at which specific types of NMIs begin to form. A comparison of experimental and calculated results showed that the proposed model adequately describes the process of formation of non-metallic inclusions in the steel under consideration and can be used for the development of industrial technology.

Lightweight Fe47Mn25Al13Cr7Ni5C3 medium-entropy alloy with enhanced mechanical properties

In this study, we designed a lightweight Fe47Mn25Al13Cr7Ni5C3 medium-entropy alloy (MEA) (calculated density of 6.803 g/cm3) with enhanced mechanical properties. The MEA samples were produced in three conditions with varying microstructures via thermomechanical processing. They achieved excellent tensile properties through strengthening mechanisms such as partial recrystallization, ultrafine grains, and M23C6 and B2 precipitates. Different strengthening mechanisms were applied depending on the annealing heat treatment conditions, resulting in three different strength-elongation combinations. Furthermore, the MEA, under all designed conditions, exhibited superior specific yield strength-uniform elongation and specific ultimate tensile strength-uniform elongation combinations compared to previously studied lightweight high-entropy alloys (HEAs) and lightweight steel. This was primarily attributed to the combination of benefits obtained from the low proportion of iron (47 at%) as a principal element and the large amount of aluminum addition (13 at%). The proposed MEA and its design strategy can satisfy the requirements for lightweight, cost-effective, strong, and ductile metallic materials, making a great contribution to the automotive industry in terms of crash resistance and fuel efficiency.