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To clarify the formation mechanism of clogging on submerged entry nozzle of Q355 steel, scanning electron microscope‐energy dispersive spectrometer (SEM‐EDS), cathodoluminescence and FactSage7.1 thermodynamic software are used to study the morphology and stratified structure of Q355 steel nozzle. The results show that, clogging on Q355 steel can be divided into decarburized layer, ≈1.5 mm, dense accumulation layer, about 2 mm, and loose accumulation layer, ≈1.5 mm. The phenomenon of CaO·2Al2O3, CaO, Ti2O3, Al2O3, and 2CaO·Ti2O3 inclusions precipitated from the molten steel and deposited in the inner wall of the nozzle during continuous casting is analyzed. The formation mechanism of the clogging is explained by drawing the clogging process diagram and thermodynamic calculation. The range of total Ca content in molten steel which should be controlled between 0.0012% and 0.0016% to reduce clogging at the nozzle is given. [ABSTRACT FROM AUTHOR]

The influence of different calcium-containing alloys on inclusions in high-Al steel is investigated in the current study. The effects of SiCa, AlCa20, AlCa75 and FeSi alloys on the modification of solid inclusions in molten steel are compared, and the mechanism of inclusion evolution is revealed based on the non-uniform distribution of elements and the lattice mismatch between the inclusion particles. The results show that the Ca yield of FeSi alloy is 26%, which is significantly higher than that of other alloys (<5%). In addition, the calcium treatment by FeSi alloy causes less aspiration of molten steel, which is conducive to avoiding the increase of AlN in high-Al steel. After calcium treatment, the primary Al2O3 particles in steel are transformed into CaO-Al2O3-CaS and CaO-Al2O3-MgO complex inclusions, while AlN can only be precipitated in the form of a single particle, or precipitated from the transformed CaO · 2Al2O3 oxide. In general, FeSi alloy has the best effect on the modification of Al2O3 inclusions, which can maximize the transformation of solid particles into liquid inclusions in steel liquid without introducing too much impurities. [ABSTRACT FROM AUTHOR]

Space weathering records provide insights to better understand the formation and evolution of the lunar regolith. Ilmenite has contrasting responses to different space weathering processes. However, the atomic‐scale structural modification of ilmenite induced using different space weathering processes remains poorly understood. Here, we investigate the effects of spacing weathering on lunar ilmenite grains returned from Chang'e‐5 (CE‐5) mission using a combination of transmission electron microscopy and thermodynamic modeling approaches. Experimental results show that melt shock induces the formation of twining structures and vein‐like Si‐Ca‐rich nanostructures in the outermost and sub‐outermost layers of ilmenite, respectively. In contrast, solar wind causes the formation of multilayered nanostructures surrounding the ilmenite grains. These structures are characterized by an outermost amorphous Si‐rich vapor deposited layer, a middle layer rich in titanium (Ti) oxides and zero‐valent iron (Fe0) nanoparticles, and an innermost layer hosting crystallographic orientation defect. The Ti oxides were identified as poorly crystallized anatase. Thermodynamic calculations indicate that the disruptive sputtering of solar wind and the reduction of hydrogen under lunar surface pressure conditions can promote ilmenite transformation into Fe0 and Ti oxides; nevertheless, the pressure increase associated with melt shock can lead to a rise in the decomposition temperature of ilmenite. In other words, solar wind irradiation plays a more significant role in promoting nanoparticle (such as anatase and Fe0) formation as compared to melt shock. Thus, unlike the chemical alteration of ilmenite induced by the solar wind irradiation, melt shock mainly causes physical changes in ilmenite grains. Plain Language Summary: Ilmenite is believed to be a major source of economically important lunar minerals. It has contrasting responses to different space weathering processes. In this work, we reported the effect of solar wind irradiation and melt shock on the microstructural features of ilmenite grains from Chang'e‐5 (CE‐5) lunar soils. Experimental results show that the solar wind could induce the chemical transformation of ilmenite into TiO2 (anatase) and zero‐valent iron (Fe0), while melt shock tends to generate physical changes such as twining and vein‐like defects. Thermodynamic calculations indicate solar wind irradiation plays a more significant role in promoting nanoparticle formation as compared to melt shock. Although both solar wind irradiation and shock events have different influences on ilmenite, their synchronic occurrence generates valuable resources (e.g., Fe0, He, Ti, and H2O) in lunar regolith. Key Points: Solar wind irradiation can induce the transformation of ilmenite into Fe0 and anataseMelt shock mainly leads to physical changes of ilmenite such as twining and vein‐like structureSolar wind irradiation plays a more significant role in ilmenite transformation as compared to melt shock [ABSTRACT FROM AUTHOR]

It is of great significance to realize the carbonation of Ca/Mg minerals in the basic oxygen furnace (BOF) slag. In this paper, the BOF slag was treated with hydrochloric acid and acetic acid, and the carbon dioxide storage test was carried out. The sample of the BOF slag was treated with acetic acid, in which the content of calcium, magnesium, and silicon accounted for 45.44%, 8.23%, and 6.83%, respectively, and has a BET surface area of 52 m2/g. The thermodynamic analysis results were that the BOF slag can react with carbon dioxide at room temperature to form carbonate. However, better kinetic conditions were needed to obtain the maximum carbon dioxide absorption capacity. The amount of carbon dioxide absorbed by the sample at 25–900 °C was measured. The results showed that in the range of 50–400 °C, the largest amount of carbon dioxide was absorbed by the sample treated with acetic acid, and the absorption amount was between 2.6 and 4.1 mmol/g. In the range of 500–800 °C, the largest amount of carbon dioxide absorbed was lime treated with acetic acid and hydrochloric acid, and the absorption was between 4.2 and 6.0 mmol/g. In the 800–900 °C range, the largest amount of carbon dioxide was absorbed, and the absorption was between 6.0 and 6.9 mmol/g via the samples treated with acetic acid and hydrochloric acid. [ABSTRACT FROM AUTHOR]

In this paper, the directional modification behavior of rare earth Ce on sulfide inclusions in steel is studied by thermodynamic calculation and experiment methods, and the mechanism of directional modification of rare earth Ce on sulfide inclusions in U71Mn heavy rail steel is proved. The results show that U71Mn heavy rail steel contained more large-sized inclusions and their distribution is more concentrated without the addition of rare earth Ce element. After the addition of rare earth Ce element, the average size of sulfur-containing inclusions in the steel decrease from 5.22 μm to 1.85 μm, and the number density of sulfur-containing inclusions in the steel increase from 83.65 mm−2 to 217.68 mm−2, indicating that the number of sulfur-containing inclusions in the steel increases after the addition of Ce element, and more small-sized sulfur-containing inclusions will form in the steel. The addition of rare earth Ce element can effectively reduce the existence of large-sized inclusions in the steel and modify large-sized inclusions into small-sized inclusions.

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The wetting behaviors of Al-Si-Cu-Mg-Zn brazing materials on 5083 aluminum alloy substrate were investigated through changing the proportion of Mg from 0 to 2 wt.%. The experimental results showed that the welding process goes through the three following stages: slow spreading, fast spreading, and stabilizing. The wettability of the brazing material was improved effectively, and the porosity of the interfacial layer was reduced, with the addition of Mg. With Mg content at 1 wt.%, the wetting diameter reached a maximum value of 20.46 mm. The reaction mechanism of the wetted interfacial layer between the brazing material and substrate alloy was illustrated with dynamic data, provided through experimentation and simulated thermodynamic calculation, and showed that the wetting behavior of the resultant Al-7.5Si-15Cu-1Mg-5Zn brazing material was dominated primarily by a diffusion reaction from elemental magnesium. [ABSTRACT FROM AUTHOR]

This study utilized Fe, Co, Ni elemental powders alongside GH3230 pre-alloyed powder as raw materials, employing high-throughput additive manufacturing based on laser powder bed fusion in situ to alloying technology to fabricate the bulk samples library for GH3230 superalloy efficiently. A quantitative identification algorithm for detecting crack and hole defects in additive manufacturing samples was developed. The primary focus was to analyze the composition variations in specimens at varying Fe, Co, and Ni elemental compositions and their impact on crack formation. Experimental results demonstrated that increased laser power improved element distribution uniformity but it proved to be not significantly effective in reducing crack defects. Moreover, augmented Fe and Co alloying content could not eliminate these defects. However, elevated Ni content led to a decrease in the alloy's solidification cracking index and carbide reduction in solidification products. Notably, a significant reduction in cracks was observed when the Ni content of the alloy reached 63 wt.%, and these defects were nearly eliminated at 67 wt.% Ni content. [ABSTRACT FROM AUTHOR]

Factsage is a robust thermodynamic calculation software that enables simulation and computation of complex multi-component and multi-phase system reactions. It has a variety of application fields such as metallurgy, energy, and environmental domains. This article elucidates the key functionalities of Factsage's diverse modules, including Equilib, Viscosity, EpH, Reaction, and Phase Diagram modules. Furthermore, it delineates the present usage and research progress of the software in the realms of air pollution, water pollution, and solid waste treatment. By predicting the thermodynamic properties of pollutants, their chemical reactions, and complex phase changes, Factsage provides a critical scientific foundation for environmental decision-making and optimization of waste treatment processes. It showed its greater contributions to environmental protection and sustainable development. [ABSTRACT FROM AUTHOR]

Lewisite is a representative chemical warfare agent that contains arsenic. Thermal decomposition is an essential method for Lewisite destruction, and appropriate destruction conditions can enhance the environmental friendliness of this method by minimizing the hazards of destruction products. In this study, the variation of Lewisite during pyrolysis and incineration was calculated, with particular emphasis on the evolution behaviors of arsenic and chloride with temperature, pressure, and molar ratio. The main products identified during pyrolysis were HCl(g), C, As, and AsCl3(g). Under anoxic conditions, AsCl3(g) and As were the dominant species. In oxygen‐enriched conditions, arsenic existed primarily as AsCl3(g), As2O5, As2O4, and AsOCl. Below 600 °C, arsenic predominantly existed in high valence forms such as As2O5. Above 600 °C, the binding capacity of chlorine and arsenic was stronger than that of oxygen, resulting in an AsCl3(g) molar fraction exceeding 75 % at 1200 °C. The primary chlorides in oxygen‐enriched conditions were Cl2(g), HCl(g), AsCl3(g), and Cl(g). Lower incineration temperatures (around 500 °C), sufficient oxygen conditions (molar ratio above 4 : 1), and positive pressures were conducive to reducing the toxicity of destruction products. The results are in good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

The precipitation, growth, and transformation of carbides rich in Cr and Mo during solidification and cooling process of high‐alloy steel for cold working dies are investigated. The Fe–C pseudobinary phase diagram of high‐alloy steel is calculated by Thermo‐Calc software to ascertain the critical phase transformation temperatures. The temperatures of phase transformation during the solidification process are determined by a differential scanning calorimeter. Then the microstructure of the samples at these characteristic temperatures is observed in situ by high‐temperature confocal microscope. The results show that the characteristic temperatures for phase transformation and carbide precipitation are 1380, 1315, 1140, and 980 °C, respectively. At 1315 °C, thick rod‐like or island‐like M7C3 carbides enriched in Cr and Fe are formed. At 1140 °C, secondary M7C3, adhering to the primary eutectic M7C3, grows rapidly in a rod‐like morphology and maintains a similar composition. The secondary M6C carbides of segregated Mo elements precipitate in fan‐shaped clusters near M7C3 through the dissolution of M7C3 and the conversion of M2C. Thermodynamic calculation further indicates that the eutectic Cr7C3 precipitates at 1213 °C, and secondary Cr7C3 remains under conditions favorable for precipitation below the solidus, preceding the precipitation of secondary carbides Cr23C6 and Mo2C. [ABSTRACT FROM AUTHOR]

Laser direct energy deposition (LDED) exhibits great potential for application in rail repairing due to its low cost and high process automation. However, the martensite transformation accompanied by rapid solidification leads to the decrease in the mechanical properties and threatens the service safety. In this study, the reinforcement strategy of combining cobalt (Co) addition with preheating treatment was investigated systematically by combining thermodynamic calculations with experimental characterization to optimize the microstructure and mechanical properties of U75V steel by LDED. The results indicate that cobalt addition can promote the pearlite percentage by facilitating the leftward shift of the continuous cooling transformation (CCT) curve, and refining the interlamellar spacing. But the martensite start (Ms) temperature will also increase from 206.4 °C to 324.1 °C after 7 wt% Co addition. 350 °C preheating treatment on the substrate can also promote the pearlite transformation by elevating the valley temperature of thermal cycling over Ms, as well as the subsequent decrease in cooling rate, but it is not sufficient to prevent martensite formation. A synergistic reinforcement strategy of 7 wt% Co addition and 350 °C preheating was established, which can effectively suppress the occurrence of martensite in the bottom area of deposition layers and expand the pearlite range in the top area. The bonding strength between the substrate and deposition layers has been elevated by ∼20%, accompanied by the increase in elongation and wear resistance. A mixed mode of adhesive and abrasive wear has transformed into a mode dominated by adhesive wear after optimization.

The Al-Mg-Si alloy plate produced by traditional hot rolling has many defects such as complicated processes， long time and high cost， which seriously restricts the development of Al-Mg-Si alloy. Therefore， the Al-Mg-Si alloy plate produced by the twin-rolling casting process has attracted great attention in recent years. The twin-rolling casting process was used to prepare the Al-Mg-Si aluminum alloy plate， and the difference of microstructure at different positions of the plate and the influence on the performance were investigated. The results show that the grain morphology of the edge and the center of the plate is significantly different， the texture composition is complex， a large number of second phases are unevenly distributed along the grain boundary， and there is obvious element segregation inside the plate. According to the theoretical calculation， the contribution strength of texture strengthening at the edges of the twin-rolling casting plate is 10.7 MPa and the contribution strength of grain boundary strengthening is 86.8 MPa， while the contribution strength of texture strengthening in the center of the twin-rolling casting plate is 15.1 MPa and the contribution strength of grain boundary strengthening is 82.4 MPa. The contribution of plate texture and random texture to the strength is limited， and the strength difference between edge and center mainly depends on the grain boundary strengthening. Different degrees of dislocation tangles exist at the edge and the center， and the dislocation density at the edge is higher than that at the center， which is consistent with the statistical results of low angle grain boundaries. According to the characteristics of microstructure inhomogeneity of the plate， the theoretical guidance for the subsequent heat treatment system of the plate is provided through thermodynamic calculation.

The combination of thermodynamic calculation and machine learning was used to reverse design nickel-based superalloys for thermodynamic performance requirements. The results show that the thermodynamic calculation dataset of nickel-based superalloys is successfully constructed by high-throughput thermodynamic calculations， which provides the data basis for the reverse design of nickel-based superalloys with thermodynamic performance requirements by using machine learning methods. Several C2P models are established for the thermodynamic target performance， and the accuracy of the models is higher than 99%. MLDS method is used to reverse design the alloy composition， and the eight alloys are recommended to meet the performance requirements （Vγ'，1100 ℃≥60%，Vγ，1100 ℃+Vγ'，1100 ℃≥99% and Tγ′≥1300 ℃）. The experimental verification of the three alloys with the smallest prediction error of thermomechanical properties shows that the Vγ'，1100 ℃ are greater than 80%， Vγ，1100 ℃+Vγ'，1100 ℃≥99% in the microstructure after aging， and Tγ′≥1300 ℃， which meet the design requirements.

HfO2 coatings with a thickness of approximately 8 μm were prepared on the refractory metals Mo surface by using chemical vapor deposition(CVD), and the reaction process of CVD HfO2 was thermodynamically analyzed by HSC Chemistry.The microscopic morphology, self-oriented growth and nanomechanical properties of HfO2 coatings were analyzed, and the bonding force of the coatings with the substrate and thermal shock resistance were tested. The results show that the HfO2 coating is well bonded to the substrate, and no macroscopic flaking occurs on the surface of the coating after 100 cycles of thermal shock from 25 ℃ to 2000 ℃; the adhesion of the coating is about 23 N as determined by the scratch test; the average emissivity of the surface of the coating is 0.48 in the band of 2.5-5 μm, which improves the average emissivity of Mo in the band by nearly 5 times.

Large-sized titanium-containing inclusion clusters seriously affect the continuous casting and performance of high titanium wear-resistant steel. In the current work, thermodynamic calculations were firstly conducted to predict the formation of various complex TiN inclusions, viz, TiOx-TiN, Al2O3–TiN and LaAlO3–TiN. Based on that, laboratory-scale experiments were designed to prepare samples containing a single type of complex TiN inclusions. The agglomeration characterizes of different complex inclusions were compared by combing in-situ observation based on confocal laser scanning microscopy and Newtonian motion equation. Furthermore, the Kralchevsky-Paunov model was used to study the influences of density and size on the agglomeration behavior of complex TiN inclusions. The result shows that the attractive force between TiOx-TiN complex inclusions increases from 1.93 × 10−18 to 4.34 × 10−17 N, while it was 3.41 × 10−17 to 5.12 × 10−16 N for Al2O3–TiN complex inclusions and 6.42 × 10−18 to 1.14 × 10−16 N for LaAlO3–TiN inclusions. Based on the experimental results and theoretical calculation, the agglomeration tendency of Al2O3–TiN is the strongest due to the considered size and compared to the TiOx-TiN inclusions, the stronger agglomeration tendency of LaAlO3–TiN ones can be attributed to their higher density.

Many factors impact the formability of single phase high-entropy pyrochlore ceramics (HEPCs) which become a research hotspot owing to their excellent properties. To investigate the effect of size disorder, two combinations with same mixing entropy and different size disorder were designed, thermodynamic analysis of first-principles calculations and experimental research were conducted in this paper. The calculation results reveal that the enthalpy change decreases significantly with the decrease of size disorder, promoting the synthesis of single-phase high-entropy pyrochlore. The experimental results prove that the combination with lower size disorder leads to single-phase HEPCs, and the prepared material exhibits low thermal conductivity (1.68 W/(m·K)) and low theoretical density (5.73 g/cm3). [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Carbon dioxide fixation presents a potential solution for mitigating the greenhouse gas issue. During carbon dioxide fixation, C1 compound reduction requires a high energy supply. Thermodynamic calculations suggest that the energy source for cofactor regeneration plays a vital role in the effective enzymatic C1 reduction. Hydrogenase utilizes renewable hydrogen to achieve the regeneration and supply cofactor nicotinamide adenine dinucleotide (NADH), providing a driving force for the reduction reaction to reduce the thermodynamic barrier of the reaction cascade, and making the forward reduction pathway thermodynamically feasible. Based on the regeneration of cofactor NADH by hydrogenase, and coupled with formaldehyde dehydrogenase and formolase, a favorable thermodynamic mode of the C1 reduction pathway for reducing formate to dihydroxyacetone (DHA) was designed and constructed. This resulted in accumulation of 373.19 µmol·L−1 DHA after 2 h, and conversion reaching 7.47%. These results indicate that enzymatic utilization of hydrogen as the electron donor to regenerate NADH is of great significance to the sustainable and green development of bio-manufacturing because of its high economic efficiency, no by-products, and environment-friendly operation. Moreover, formolase efficiently and selectively fixed the intermediate formaldehyde (FALD) to DHA, thermodynamically pulled formate to efficiently reduce to DHA, and finally stored the low-grade renewable energy into chemical energy with high energy density. [ABSTRACT FROM AUTHOR]

The micro-sintering method was used to determine the sintering basic characteristics of iron ore with Zn contents from 0 to 4%, the influence mechanism of Zn on sintering basic characteristics of iron ore was clarified by means of thermodynamic analysis and first-principles calculations. The results showed that (1) increasing the ZnO and ZnFe2O4 content increased the lowest assimilation temperature (LAT) but decreased the index of liquid phase fluidity (ILF) of iron ore. The addition of ZnS had no obvious effect on LAT but increased the LIF of iron ore. (2) ZnO and ZnFe2O4 reacted with Fe2O3 and CaO, respectively, during sintering, which inhibited the formation of silico-ferrite of calcium and aluminum (SFCA). The addition of ZnS accelerated the decomposition of Fe2O3 in the N2 atmosphere; however, the high decomposition temperature limited the oxidation of ZnS, so the presence of ZnS had a slight inhibitory effect on the formation of SFCA. (3) The Zn concentrated in hematite or silicate and less distributed in SFCA and magnetite in the form of solid solution; meanwhile, the microhardness of the mineral phase decreased with the increase in Zn-containing solid solution content. As the adsorption of Zn on the SFCA crystal surface was more stable, the microhardness of SFCA decreased more. The decrease in microhardness and content of the SFCA bonding phase resulted in a decrease in the compressive strength of the sinter. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

When the calculation of phase diagram (CALPHAD) method is applied to the Au-Ag-Al ternary phase diagram, the accuracy of three marginal binary phase diagrams (Au-Al, Au-Ag, Ag-Al) has a great impact on the calculating results. At present, there are some contraditions in the Au-Al marginal binary phase diagram. Therefore, based on a comprehensive evaluation of experimental data for the Au-Al system, the equilibrium phase diagrams were optimised and calculated by using a solid solution model to describe the Gibbs free energy of the liquid, Bcc and Fee phases in the Au-Al system, and by using the sublattice models (Al)(Au)4, (Al)3(Au)8, (Al)(Au)2, (Al)(Au) and (A1,AU)2(A1,AU) to describe the A1AU4, Al3Au8, A1AU2, AlAu and AL2Au phases. A set of reasonably self-consistent thermodynamic parameters was obtained via optimizing with Pandat software. Au-Al phase diagrams calculated in this way agreed well with the experimental and thermodynamic data. Combined with thermodynamic parameters of Au-Ag and Ag-Al, the Au-Ag-Al liquid-phase, surface projections and isothermal cross-sections were calculated. The liquid- phase surface projections revealed the existence of eight four-phase equilibrium reactions in this ternary system, and these results may be helpful in studying the Au-Ag-Al alloys. [ABSTRACT FROM AUTHOR]

The paper deals with thermal analysis and the mode of heat dissipation on the surfaces of the 3D printer parts. The paper presents both the 3D modelling part of the components related to the E3D Volcano assembly, the realization of the simulation models using the necessary conditions for the heat transfer phenomenon, more precisely in the current study we will only use thermal convection and thermal radiation as well as the realization of a mathematical calculation regarding the thermal part using real values. Very important in this case are also the materials used for each part of the assembly because they play an important role in heat transfer regarding thermal conductivity. Also, in the final part of the paper, the simulation after the mathematical power calculation is proposed regarding the evolution of the temperature on the entire E3D Volcano assembly and the graphic representation of the diagram T [°C] according to the power of the resistance P [W]. [ABSTRACT FROM AUTHOR]

The diminutive additions of nickel (Ni) element have been fused to Sn-1.5Ag-0.5 mass% Cu (SAC155) lead-free solder alloy. The study was examined experimentally and computationally (using JMatPro software program) the microstructural features, thermal behavior, density, thermal diffusivity, and conductivity as well as tensile stress strain of the Sn-1.5Ag-0.5Cu-x mass %Ni (x = 0.00, 0.05, 0.10, 0.20, and 0.50) solder alloys (SAC155-xNi). The fusing additions of Ni have a little impact on the melting point of SAC155 alloy which increasing from 502 to 504.2 K . The microstructure of SAC155 solder alloy included coarse grains of β-Sn besides, large eutectic regions, and embedded IMCs of Ag3Sn and Cu6Sn5. The computed values of Gibbs free energy (G) during solidification of the β-Sn phase, Ag3Sn, and Sn3Sn4 IMCs show the stability at - 130.7 × 10 3 J.kg - 1 , - 157.7 × 10 3 J.kg - 1 , and - 377.13 × 10 3 J.kg - 1 , respectively. The SAC155-xNi alloys involved finer β-Sn grains, large fibrous eutectic regions, (Cu,Ni)6Sn5 and (Cu,Ni)3Sn4 IMCs. The G of Cu6Sn5 decreased from - 233.1 × 10 3 J.kg - 1 to - 317.9 × 10 3 J .kg - 1 when Ni content increased up to 0.25 mass %, then stable and steady at - 318.4 × 10 3 J.kg - 1 with more addition of Ni element. The formation of the (Cu, Ni)6Sn5 and (Ni, Cu)3Sn4 IMCs is motivated by the lowest Gibbs free energy, especially when Ni mass% is added to a sufficient level. The measured and computed values of specific heat at constant pressure (Cp) of SAC155-xNi alloys show a good matching especially at lower temperatures and a little mismatch at high temperatures which decreases with increasing Ni content. The activation energy of atomic arrangement (Q) increased from 11.36 to 13.41 kJ.mole - 1 with increasing Ni content in SAC155-xNi alloys. Thermal diffusivity (α) and conductivity (κ) of SAC155-xNi gradually decreased with increasing temperature in the range from 303 to 423 K and/or Ni content in alloys. The measured values of (κ) are slightly lower than the computed value at similar temperatures of the SAC155-xNi alloys. The decrease in (κ) may be assigned to scattering the electrons or reducing the phonon contributions due to the presence of various solute atoms and different IMCs. The results of stress-strain graphs reveal the enhancement of YS and UTS for all Ni-containing alloys. The improvement of the yield stress (YS) and ultimate tensile strength (UTS) of Ni-containing alloys is attributed to the uniform distribution of the IMCs, the reduction of β-Sn grain size, and the smoothed enlargement of the eutectic region. [ABSTRACT FROM AUTHOR]

Titanium matrix composites with high TiC content have multiple excellent properties. However, their dendritic TiC morphology poses challenges to their room-temperature plasticity. In this study, (TiC + TiB)-reinforced titanium matrix composites were developed by incorporating B 4 C into dendritic TiC composites. The impact of B 4 C additions on the microstructure evolution and mechanical properties of dendritic TiC in the composites was systematically investigated. The results revealed that the in-situ synthesis of TiC and TiB significantly refines the matrix grains of the composites with the addition of B 4 C. Notably, TiB serves as a nucleation substrate for dendritic TiC, forming an intergrowth microstructure of TiC and TiB during solidification–precipitation. This effectively reduces the number of dendritic TiC. The interfacial orientation relationships between TiC and TiB were studied through high-resolution transmission electron microscopy, revealing [110] TiC //[311] TiB and (111) TiC //(210) TiB , with a two-dimensional lattice mismatch of 6.43% between (111) TiC and (210) TiB. At room temperature, the ultimate tensile strength and fracture strain of the composite with 1 wt% B 4 C were 1059.52 MPa and 5.58%, respectively. Compared with the original composite, the tensile strength increased by 39.4%, and the corresponding elongation was remarkably increased. This enhancement is attributed to the synergistic strengthening effect and fine grain strengthening effect of the intergrowth structure of TiC and TiB in the composite. The microstructure refinement mechanism and strengthening mechanism are discussed in detail, providing new ideas and methods for the design and preparation of composites. [ABSTRACT FROM AUTHOR]

Multi-component high entropy oxides (HEOs) have attracted enormous attention due to their unique structures and potential applications. The conventional selection strategy to obtain HEOs is to search for equimolar cationic systems to maximize configurational entropy and avoid phase separation. We previously explored non-equimolar cationic rocksalt structure Mg–Co–Ni–Cu–Zn–O HEOs using cluster-plus-glue-atom model. In this paper, the mixing entropy, enthalpy and Gibbs free energy of constructed superclusters were numerically calculated and compared with the correlated crystal structure based on recent studies. It indicated the Gibbs free energy rather than mixing entropy agrees well with the phase stability of HEOs. Mg 28 Co 17 Ni 19 Cu 16 Zn 16 O 96 shows the optimal phase stability which is related to the lowest Gibbs free energy, reflecting a regular octahedral environment preferred by the cation composition in the system. Enthalpy and entropy are among important design criteria in determining the phase stability of HEOs but the function of enthalpy is obviously higher than that of entropy. This study provides a comprehensive way to access HEOs which is undoubtedly very important for the development of other non-equimolar cationic high entropy materials such as carbides, silicides, borides or nitrides. [ABSTRACT FROM AUTHOR]

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Copyright of Iron Steel Vanadium Titanium is the property of Iron Steel Vanadium Titanium Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Tire recycling is becoming an increasingly important problem due to the growing number of end-of-life tires (ELTs). World-wide, ELTs account for more than 80 million tons. ELTs contribute to environmental pollution in the long term. They are flammable, toxic and non-biodegradable. At the same time, ELTs contain rubber, metal and textile cord, which are valuable raw materials. ELTs are buried in landfills, burned, crushed and restored. Most of these methods have a negative impact on the environment. From an environmental point of view, the most preferred ways to recycle tires are retreading and shredding. Rubber powder (RP) or crumb is mainly used for rubber pavers production, waterproofing, curbs, road slabs and various surfaces. An alternative method for RP processing, eliminating the disadvantages of the above approaches, is plasma gasification and pyrolysis. The paper presents a thermodynamic and kinetic analysis and an experiment on plasma processing of RP from worn tires to produce flammable gas. At a mass-average temperature of 1750 K, the yield of synthesis gas from plasma-air gasification of RP was 44.6% (hydrogen—19.1, carbon monoxide—25.5), and 95.6% of carbon was gasified. The experimental and calculated results satisfactorily agreed. It was found that plasma products from RP did not contain harmful impurities, either in calculations or experiments. Plasma gasification allows for recycling ELTs in an environmentally friendly way while also generating flammable gases that are valuable commodities. In this research, plasma technology was demonstrated to be effective for gasifying RP to produce flammable gas. [ABSTRACT FROM AUTHOR]

The effects of Ce treatment on the inclusion evolution and impact toughness of as‐cast transformation‐induced plasticity (TRIP) steel are systematically investigated by scanning electron microscope (SEM) and impact toughness testing. The results reveal that in Fe‐2Mn‐1.5Al‐1Si‐0.2C steel without Ce, the primary inclusions consist of AlN, MnS, and Al2O3. After Ce addition, the inclusions evolve into Ce‐Al‐O, Ce2O2S, CeS, and Ce2O3 inclusions. The evolution of inclusions exhibits an initial reduction in both quantity and size with increasing Ce content, followed by a subsequent increase. In cases of excessive Ce content, there is an observable rise in the overall inclusion count, marked by the emergence of CeAs, CeP, and CeC2 inclusions. The segregation model suggests that P‐containing inclusions predominantly precipitate in the late solidification process, while As‐ and C‐containing inclusions form during the solid phase. When the Ce content reaches 0.0075 wt%, the minimum values of the number density and average diameter are 96.7 mm−2 and 1.6 μm, respectively. Furthermore, the influence of the size, morphology, quantity, and type of inclusions on the impact toughness are analyzed. The highest recorded impact energy is 6.8 J with a Ce content of 0.0075 wt%. [ABSTRACT FROM AUTHOR]

Ferroelectric materials possessing exceptional piezoelectric attributes have garnered widespread utilization in various applications. Solid solution systems improve piezoelectric properties through multiphase mixing, but the methodologies for effective design remain wanting. Based on the Landau–Devonshire theory, we propose a theoretical design method. Binary materials with morphotropic phase boundary (MPB) compositions are added with new elements to increase the free energy of the original stabilized phase and lower the energy barrier (EB). Flatter EBsand higher piezoelectric coefficients are found at the phase boundaries of the ternary system. By calculating the phase diagram, piezoelectric coefficient, dielectric constant, polarization, and EBs, we reveal the origin of the highest piezoelectric coefficient at the phase boundaries. This study underscores the importance of the EBs for polarization rotation in characterizing piezoelectric properties and proposes a theoretical design method for exploring materials with high piezoelectric coefficients. [ABSTRACT FROM AUTHOR]

The article focuses on the results of water parameters (COD, pH, electrical conductivity) and the contents of major ions (Ca2+, Mg2+, Na+, K+, , , Cl–, , ) and trace elements (Co, Ni, Cu, Zn, Cd, Pb, Sr, Ba, Mn) for 12 springs in the Bogorodsky and Losino-Petrovsky districts of Moscow oblast. The waters are slightly acidic to near-neutral (pH 5.5–7.5) with the mineralization ranging from 0.07 to 0.5 g/L, the total hardness is 0.63–5.7 mg-eq/L, the water composition is variable. Spring waters are divided into four groups: Cl–SO4–HCO3–(Mg)–Ca, (SO4)–HCO3–Cl–Na–Ca; (Cl)–HCO3–Ca, and mixed. Based on the thermodynamic calculation using the Visual-MINTEQ program, it was found that the predominant dissolved species of Ba, Sr, Mn, Zn, Cd, Ni, and Co in the waters of the surveyed springs are free ions. For Cu and Pb, the factors for the formation of migration species are the predominant anions of water, as well as the presence of organic matter in water. The COD values and nitrogen compound in the waters of individual springs indicate that the formation of the spring water composition is resulted from the infiltration of atmospheric precipitation through the modern sediments subject to anthropogenic loading. The values of other sanitary–chemical indicators (mineralization, pH, total hardness, chlorides, sulfates, magnesium, sodium, manganese), the content of regulated trace elements are lower than their maximum permissible concentrations in drinking water. [ABSTRACT FROM AUTHOR]

PIP-prepared SiC f /SiC composite joints were brazed by using Cu-Ni-Ti filler alloys, composed of region I: Ni 16 Si 7 Ti 6 +NiSi 2 /NiSi/Ni 3 Ti+TiC x +Cu and region II: TiC x +Cu and infiltration region. The individual and coupled reactions between Cu/Ni/Ti elements and SiC f /SiC composites were clarified experimentally and thermodynamically. The infiltration region was first confirmed to be amorphous Cu-Si-C or Si-C matrix, Cu or Cu(C), (Cu, Ni) 15 Si 4 , and Ni 2 Si. The joint strength was related to the carbonization and amorphization in the infiltration region and the compound content in region I. Three interfaces of vertical fiber-seam, parallel fiber-seam, and matrix-seam were different because of the inhomogeneous features of SiC f /SiC composites. The crystallinity of SiC and the residual free carbon affected the reaction kinetics of the Ti element. The PyC coating produced compact TiC x grains that consequently served as a diffusion barrier for the parallel fibers. The topology of the fibers affected the infiltration region by forming a "capillary action". [ABSTRACT FROM AUTHOR]

In present study, a high-efficiency CaO–SiO 2 –Al 2 O 3 –MgO slag was designed to dissolve alumina particles, and the in situ observation for alumina particles dissolution by CSLM instrument equipped with color fast CCD camera was conducted, which broke through the limitations of the original CSLM equipment. The dynamic measurements showed that the dissolution behavior of alumina particles was controlled by diffusion. Moreover, the mechanism of dissolution of alumina particles was illustrated by combining SEM-EDS detection and thermodynamic calculations. It was found that there was an about 3 μm distinct interface layer when alumina particles were dissolved in slag, and the formation order of products of the interface layer was closely related to its thermodynamics. In addition, the apparent activation energy of reaction between Al 2 O 3 and CaO was used to calculate the reaction time of alumina particles with different particle size, and the viscosity values of the all slags obtained by the Factsage 8.2 thermodynamic software and Stocks-Einstein theory were used to calculate the time required for diffusion of alumina particles with different particle sizes. Compared the total time of chemical reaction and the diffusion mass transfer, it is found that when the radius of alumina particles is greater than 2.5 μm, the dissolutions of alumina particles in all CaO–SiO 2 –Al 2 O 3 –MgO slag composition points are controlled by diffusion. [ABSTRACT FROM AUTHOR]

In this study, the formation and characteristics of inclusions in S32101 duplex stainless steel (DSS) during continuous casting were investigated by analyzing inclusions in the tundish and continuous casting slabs. The composition of inclusions changed significantly during the continuous casting. The inclusion type in the tundish was primarily CaO-SiO2-Al2O3-MgO-MnO. There are two types of inclusions in the continuous casting slab: CaO-SiO2-Al2O3-MgO-MnO inclusions with dense Al2O3 and MnO, and Al2O3-MnO inclusions. TiN wraps the outer layers of both types of inclusions. The results obtained from thermodynamic calculations agreed with the experimental results. The weight percentage of Al2O3 and MnO in the inclusions increases significantly with the solidification process. In addition, the Al2O3-MnO inclusions were formed in the slab. TiN precipitates during the solidification of the S32101 DSS. The CaO-SiO2-Al2O3-MgO-MnO and Al2O3-MnO inclusions can be used as the nucleation sites of TiN. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Iron Steel Vanadium Titanium is the property of Iron Steel Vanadium Titanium Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The processes in an oxygen–methane combustion chamber with gaseous fuel are studied by three-dimensional numerical modeling. The advantages and disadvantages of the modeling method based on the gross reaction equation for the stoichiometric composition are considered. Eddy dissipation is considered as the model of combustion. The working fluid is assumed to be an ideal gas. The behavior in the combustion chamber according to modeling is analyzed. The results of three-dimensional modeling and thermodynamic analysis are compared. Recommendations are made for improving the design and efficiency of the combustion chamber. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering for Thermal Energy & Power / Reneng Dongli Gongcheng is the property of Journal of Engineering for Thermal Energy & Power and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)