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Copyright of Precious Metals / Guijinshu is the property of Precious Metals 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 Foundry Technology (1000-8365) is the property of Foundry Technology 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.)

With the rapid development of new energy fields and the current shortage of lithium supply, an efficient, clean, and stable lithium resource extraction process is urgently necessary. In this paper, various advanced detection methods were utilized to conduct a mineralogical analysis of the raw ore and systematically study the occurrence state of lithium; the limestone sintering process was strengthened and optimized, elucidating the sintering mechanism and analyzing the leaching process kinetics. Under an ingredient ratio of 1:3, a sample particle size of 300 mesh, a sintering temperature of 1100 °C, a sintering time of 3 h, a liquid–solid ratio of 2:1, a leaching temperature of 95 °C, and a leaching time of 1 h, the leaching rate of Li reached 90.04%. The highly active Ca–O combined with Si–O on the surface of β–spodumene to CaSiO4, and Al–O was isolated and combined with Li to LiAlO2, which was beneficial for the leaching process. The leaching process was controlled by both surface chemical reactions and diffusion processes, and Ea was 27.18 kJ/mol. These studies provide theoretical guidance for the subsequent re-optimization of the process. [ABSTRACT FROM AUTHOR]

Copyright of Nonferrous Metals (Extractive Metallurgy) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group 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.)

With high melting point, high hardness, high thermal conductivity, excellent electrical conductivity, and high temperature oxidation resistance, the TiB2 ceramic has been applied in the fields of aerospace, machinery manufacturing, metal smelting, electronic information, and so on. However, the high-end manufacturing application of TiB2 ceramic has been limited by the low relative density and the difficulty of machine-processing. The densification of TiB2 ceramic could be improved by doping modification, adding sintering additives, optimizing sintering process, and so on, which significantly improves the mechanical properties. The research progress of high-performance TiB2 ceramic in terms of composition design and sintering processing was reviewed in this paper. The applications of TiB2 ceramic were also prospected on precision tools, bulletproof armor, and cathode tools.

Abstract In this study, entanglement of composition, additive and/or sintering conditions and their effects on magnetic properties of soft ferrites, nickel zinc spinel ferrites (Ni1−xZnxFe2O4, x = 0.65 and 0.70) which were prepared via conventional solid-state reaction method investigated. Also an equiponderant calcined mixture of Bi2O3, CaO, CeO2, SiO2, Al2O3, Y2O3 and nanotitania was mixed thoroughly and used as a multi-compound calcined additive (MCCA). Calcined ferrite powders were crushed, dry and wet milled, dried, mixed with different amounts of MCCA (0.0, 0.5, 1.0, 1.5 and 2.0 wt%), formed in toroidal shapes and finally sintered at different temperatures, from 1150 up to 1360 °C for 3 h. X-ray diffraction assessment confirmed formation of the single phase cubic spinel structures. Initial permeability and Q-factor spectra of the toroids were obtained from 0.1 to 1000 kHz, using an LCR meter. The results show that initial permeability of each sample has a maximum and addition of MCCA to the ferrites leads to a marvelous increase in permeabilities. Additionally, MCCA decreases the optimum sintering temperature too. The optimum amounts of additive were 1.0 and 0.5 wt% for the x = 0.65 (μ′ = 492, Ts = 1280 °C) and x = 0.70 (μ′ = 478, Ts = 1320 °C), respectively. Permeability spectra illustrate that utility zone of the Ni0.35Zn0.65Fe2O4 and Ni0.3Zn0.7Fe2O4 are both less than 100 and 10 kHz, respectively. The results represent that there is a strong entanglement between composition, additive and/or sintering conditions. It can be concluded the MCCA added Ni0.35Zn0.65Fe2O4, is suitable for application in the switching power supplies.

Flexible electronics have revolutionized the field by overcoming the rigid limitations of traditional devices, offering superior flexibility and adaptability. Conductive ink performance is crucial, directly impacting the stability of flexible electronics. While metal filler-based inks exhibit excellent conductivity, they often lack mechanical stability. To address this challenge, we present a novel conductive ink utilizing a ternary composite filler system: liquid metal and two micron-sized silver morphologies (particles and flakes). We systematically investigated the influence of filler type, mass ratio, and sintering process parameters on the composite ink's conductivity and mechanical stability. Our results demonstrate that flexible wires fabricated with the liquid metal/micron silver particle/micron silver flake composite filler exhibit remarkable conductivity and exceptional bending stability. Interestingly, increasing the liquid metal content results in a trade-off, compromising conductivity while enhancing mechanical performance. After enduring 5000 bending cycles, the resistance change in wires formulated with a 4:1 mass ratio of micron silver particles to flakes is only half that of wires with a 1:1 ratio. This study further investigates the mechanism governing resistance variations during flexible wire bending. Additionally, we observed a positive correlation between sintering temperature and pressure with the conductivity of flexible wires. The significance of the sintering parameters on conductivity follows a descending order: sintering temperature, sintering pressure, and sintering time. Finally, we demonstrate the practical application of this technology by integrating the composite ink-based flexible wires with conductive polymer-based strain sensors. This combination successfully achieved the detection of human movements, including finger and wrist bending. [ABSTRACT FROM AUTHOR]

In the aerospace industry, lightweight can reduce the weight of the engine and improve the thrust-weight ratio of the engine. Ceramic matrix composites have attracted widespread attention in the industry due to their much lower density compared to high-temperature alloys and excellent high-temperature performance. SiC fiber-reinforced SiC ceramic matrix composites are the most outstanding representatives, but their long manufacturing cycle and high manufacturing costs limit their widespread use. Ti 2 AlC is a new type of ceramic material with the characteristics of low density, high melting point, high-temperature resistance, oxidation resistance, and corrosion resistance of ceramic materials, as well as the conductivity and machinability of metals. However, its mechanical properties are slightly inadequate. The use of chopped fibers for toughening can compensate for these deficiencies to a certain extent and improve mechanical properties. This article first explored the influence of various process parameters on the mechanical properties of pure-phase Ti 2 AlC ceramic materials in SPS preparation technology and then prepared Ti 2 AlC composites reinforced with 10 vol%, 20 vol%, and 30 vol% Al 2 O 3 chopped fibers. The results showed that the samples prepared at 1300 °C, 40 MPa, and 10 min had a flexural strength of 697 MPa and a fracture toughness of 9.83 MPa m1/2 when the volume ratio of the reinforcement phase was only 10 vol%, which was the same as that of the continuously fiber-reinforced SiC f /SiC composites. This study showed that the MAX phase matrix composites reinforced with chopped fibers have the potential to become high-temperature structural materials by adjusting the composite composition and optimizing the preparation process. [ABSTRACT FROM AUTHOR]

The effect of CaCO3 particle size on the viscosity of slurry, phase formation, microstructural evolution, and performances of the water‐soluble CaO‐based ceramic core sintered at different temperatures was systematically investigated and discussed, and the particle gradation orthogonal experiments were used to adjust flexural strength, water‐soluble rate, shrinkage rate, apparent porosity, and hygroscopicity rate. The results showed that the finer particle size increased the effective contact area between CaO and SiO2, which promoted the generation of CaO–SiO2 system phase and the dense microstructure in the sintered CaO‐based cores. The higher sintering resulted in dense microstructure. The optimal gradation scheme included 28 wt.%, 56 wt.%, and 16 wt.% CaCO3 powder with D50 = 11.0 µm, 6.17 µm, and 4.62 µm, respectively, and the resulting flexural strength was 9.57 MPa, water‐soluble rate was 65.37 g/h in 60°C water, shrinkage rate was 8.62%, porosity rate was 38.85%, presenting a well‐balanced comprehensive performance, which is significant for the complex internal castings. [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.)

Sintered ore used as blast furnace burden materials is produced by mixing iron ore, coke, and limestone, then burning the coke and sintering the iron ore with the combustion heat. Among the coke charged, A particle size of 0.25 mm or less has an insignificant effect as a heat source and adhere to the surface of other materials to inhibit the reaction between oxygen and raw materials, thereby decreasing the quality of sintered ore. Therefore, to increase combustion efficiency, it is necessary to reduce the ratio of coke breeze in the charged coke. In this study, theoretical calculation, experiment and simulation were conducted to investigate the possibility of size classification by drag force in the process of dropping coke after being transported through a belt conveyor. The height of belt conveyor was at 1m, and velocity of the belt was 1.5, 2.3, and 2.6 m/s, which were considered as experimental variables. After falling, the distribution of coke particle size according to the horizontal travel distance was confirmed, and a fall trajectory prediction formula model was created through the drag model of polydisperse system and compared with the experimental and analysis results.

The article presents the results of obtaining a composite material by sintering nickel-containing raw materials mixed with carbon-containing materials, namely using coke and semi-coke. The sintering process was performed at a charge layer height of 240 mm and the temperature of the lower layer was T = 1200 °C. The results of the sieve analysis showed (a fraction of 10 mm) that the yield of a suitable composite material using coke was 68.3% and with semi-coke 67.0%. The average nickel and chromium content in the composite materials was 1.42% and 3.07%, accordingly. As a result of determining the strength characteristics of the obtained composite materials with various reducing agents by dropping from a height of 2 m onto a steel pallet, it was found that the obtained composite materials have high mechanical properties in terms of strength of 81% and 89.2%. The results of the elemental composition at the studied points and the thermal analysis of the studied composite material are presented. The mineralogical composition of the composite material is presented in the form of serpentine and nontronite, and the empty rock is made of quartz and talc. The activation energy of thermal analysis by the method of non-isothermal kinetics were calculated. The results of experiments on the production of composite materials from nickel-containing raw materials will be recommended for obtaining the optimal composition of composite materials at the stage of pilot tests and industrial development of the developed technology for processing nickel ores of the Republic of Kazakhstan. For the processing of nickel-poor nickel ores, it is of great importance to obtain optimal technological and technical and economic indicators that ensure low cost of nickel in the resulting product. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Minerals & Processing / Huagong Kuangwu yu Jiagong is the property of Industrial Minerals & Processing 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 Sr1-3x/2DyxTiO3 (x = 0.005, 0.01, 0.015, 0.02, 0.04, 0.06) ceramics are prepared sintered in N2 / air through a solid-state synthesis method. The effects of Dy doping amount and sintering process on the structure and dielectric properties of Sr1-3x/2DyxTiO3 ceramics were systematically investigated. We identify a novel Sr1-3x/2DyxTiO3 ceramic system sintered in N2 that exhibits the most superior dielectric performance when x = 0.01. At room temperature, the εr and tanδ of Sr0.985Dy0.01TiO3 ceramic sintered in N2 are 29,000 and 0.07 at a frequency of 1 kHz, and 27,000 and 0.01 at a frequency of 10 kHz, respectively. Additionally, the εr of Sr0.985Dy0.01TiO3 ceramics sintered in N2 has an excellent temperature stability at high temperatures, with a change rate within the range of ± 15% at a frequency of 10 kHz ranging from 30 to 480 ℃. Through comparing Sr0.985Dy0.01TiO3 ceramic sintered in air, sintering in N2 significantly improved its εr and thermal stability. This study demonstrates that the improvement of processing techniques and doping strategies have enhanced the dielectric properties of the ceramics. [ABSTRACT FROM AUTHOR]

When processed conventionally, aluminum-bronze alloys with high mechanical strength require machining after the raw state of fusion, and the waste (chips), if not reused, can cause problems for the environment and costs for the company. Therefore, this article proposes an alternative for recycling aluminum bronze through the new route via Powder Metallurgy (PM), analyzing the resulting microstructure. This study compares the microstructures of the aluminum bronze derived from extraction (the samples received - SR) and the state after the powder metallurgy (PM) process with the addition of vanadium carbides (VC). The study also analyzes the distribution of VC in the microstructure of the PM composite as well as the influence of the TQ30 heat treatment on this composite. For the PM process, aluminum alloy and bronze chips were ground together with vanadium carbide (VC) in a high-energy mill for 50 hours. The powders obtained were pressed uniaxially (400 MPa) to achieve good compaction. The samples were then sintered (900°C/1h), water quenched (900°C/2h), and subjected to treatment according to the TQ30 standard, which, in addition to the previous treatments, also includes tempering at 500°C for 2 hours (ASTM B150/B150M-12 standard). The microstructure observed in the SR samples was martensitic (in needles), with secondary phases dispersed in the matrix. On the other hand, the microstructure of the PM samples showed equiaxed grains of the alpha phase (κ), as well as the secondary phases kapa (κ) and beta line (β'), in contrast to the needle-shaped microstructure of the conventional melting process. [ABSTRACT FROM AUTHOR]

Segregation of A-site ions and microstructure evolution may result in performance degradation of composite electrode materials employed in reversible solid oxide cell (rSOC), which is highly related to particle interactions appeared during sintering and preparation procedures. In this study, both experimental and modeling methods are implemented to characterize the sintered morphology and to analyze the A-site ions migration behaviors for the perovskite material La 0.75 Sr 0.25 Cr 0.5 Mn 0.5 O 3 (LSCM) compounded with yttria-stabilized zirconia (YSZ) in the sintering process. A molecular dynamics (MD) method is further developed to predict particle diffusion and stress distribution, which is associated to the migration and segregation behaviors for LSCM-YSZ materials. The effects of the sintering temperature, nanoparticle sizes and mass composition are also studied. It is found that the particle stress of the composite materials is positively correlated with particle migration under high sintering temperature. The diffusivities of particles increase by 5.6%–19.7% when the sintering temperature increases from 1473 K to 1873 K. The diffusivities of particles and the specific surface area increase by 25.2%–47.6% and 21%, respectively, when the nanoparticle size decreases from 60 Å to 40 Å. Low stress and weak ion segregation are both achieved for the mass composition ratio of LSCM:YSZ = 2:1 in the sintering process. • MD simulation and experimental preparation for sintered LSCM-YSZ nanoparticles. • Microstructure and stress properties during sintering preparation. • Effects on the migration and segregation under sintering of LSCM-YSZ. [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 Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic 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.)

To preheat water for moistening a sinter charge, it is proposed to use a recuperative water heater installed in the gas collector of a sinter machine in the zone of the last wind boxes where the temperature of the exhaust gas reaches the maximum, which allows the maximum effect of water heating. The established dependence of the difference between the final and initial temperature of the charge on its initial temperature indicates that the water heating system in sinter production will be the most efficient at sinter charge temperatures close to 0 °C. Finite-element models for analysis of gas dynamics, heat transfer, and water heating in recuperative water heaters by the exhaust gas in the collector of a sinter machine have been developed. Diagrams of the distribution of the temperature of the fluids and the flow-average temperature of water at the collector outlet in planes located along and across the flow of the exhaust gases are plotted. It is established that the heating of the heat-transfer fluid in the water heater with the tubing parallel to the gas flow from the wind box is more intensive, the outlet water temperature being higher by 12.6 °C compared with the case where the tubing is perpendicular to the gas flow in the collector. The developed method of simulating water heating by the heat of the exhaust gas is intended to determine the rational parameters and design features of the recuperative water heater installed in the collector of a sinter machine. [ABSTRACT FROM AUTHOR]

Stereo Lithography Apparatus (SLA) has demonstrated improvements on surface-roughness and dimensional-accuracy of the precision casting prototypes in recent years, which however is still far from being satisfactory in industrial. One primary problem is the easy crack of the ceramic shell at sintering process originated from the high thermal expansion coefficient of the photosensitive resin. Herein, this paper aims to find a solution for the cracking problem of the SLA-prototyped ceramic shells. This paper introduces recent studies mainly focusing on the aspect of photosensitive resin modification, the hollow structure improvement inside the photosensitive resin prototype, the wax sheet pasting method on the weak part of ceramic shells, and the sintering process design of the photosensitive resin in ceramic shells. The performance of ceramic shells through these studies are evaluated, and a fundamental solution to the cracking problem of ceramic shells is thereafter prospected.

With the rapid development of new energy fields and the current shortage of lithium supply, an efficient, clean, and stable lithium resource extraction process is urgently necessary. In this paper, various advanced detection methods were utilized to conduct a mineralogical analysis of the raw ore and systematically study the occurrence state of lithium; the limestone sintering process was strengthened and optimized, elucidating the sintering mechanism and analyzing the leaching process kinetics. Under an ingredient ratio of 1:3, a sample particle size of 300 mesh, a sintering temperature of 1100 °C, a sintering time of 3 h, a liquid–solid ratio of 2:1, a leaching temperature of 95 °C, and a leaching time of 1 h, the leaching rate of Li reached 90.04%. The highly active Ca–O combined with Si–O on the surface of β–spodumene to CaSiO4, and Al–O was isolated and combined with Li to LiAlO2, which was beneficial for the leaching process. The leaching process was controlled by both surface chemical reactions and diffusion processes, and Ea was 27.18 kJ/mol. These studies provide theoretical guidance for the subsequent re-optimization of the process.

In this paper, we generalize the experience of using surfactants under laboratory and industrial conditions of the sintering process. The results of laboratory studies on the use of powdered polyacrylamide in agglomeration are presented. An analysis of the research results showed a positive effect of polyacrylamide on the performance of the sintering process and the quality of the sinter, which is associated with the formation of a more optimal granulometric composition of the pelletized charge and an increase in the temperature-thermal level of the sintering process. Based on the obtained laboratory data, recommendations for conducting industrial tests are formulated. [ABSTRACT FROM AUTHOR]

Developing biodegradable bone implants using magnesium-based materials has garnered significant attention in research. Magnesium offers favorable properties, such as low density, biocompatibility, elastic modulus like bone, and high toxicity limits. However, improvements are needed in mechanical properties and degradation rate. This study focuses on enhancing these properties by developing a novel composite of magnesium with carbonate apatite (CA) reinforcement, Mg/5CA. Compared to hydroxyapatite (HA), CA offers better absorption and avoids fibrotic tissue formation. However, CA undergoes carbonate decomposition during sintering, leading to composite degradation. To address this, an extrusion process is employed to prevent carbonate decomposition. The advanced sintering and extrusion compaction processes are compared for the Mg/5CA composite, examining density, microstructure, hardness, compressive strength, and biocorrosion. Results demonstrate that extrusion increases relative density while CA slightly reduces it. Microstructural analysis reveals finer and elongated grains, tighter bonding between CA and Mg particles, and reduced microporosity in the extruded composite. Mechanical properties, including hardness distribution and compressive strength, are improved in the extruded composite, and the degradation rate decreases compared to sintering. Overall, the extrusion process effectively enhances Mg/5CA composite properties, positioning it as a promising manufacturing technique for biodegradable implant materials. This research contributes to the development of advanced biodegradable implants, which can have significant applications in the field of medical science. Further investigations in this area can contribute to the ongoing advancements in biodegradable implant technology. [ABSTRACT FROM AUTHOR]

In this work, the phase composition and microstructure evolution of the Al 2 O 3 -TiO 2 -CaO composite materials were studied by sintering titanium-ferroalloy smelting slag at temperatures ranging from 1300 to 1600 °C for 3 h. Combined with thermodynamic calculation and mechanical property analysis, it could be seen that with the increase of sintering temperature, Ca ((Al 0.84 Ti 0.16) 2) 6 O 19 in ferrotitanium slag was decomposed into CaAl 12 O 19 , and the titanium-containing components were dissolved to form free rutile and CaTiO 3. The essence of the sintering behavior of the material was the liquid phase sintering, due to the presence of impurity components, the liquid phase started to form in the system at 850 °C with a content of 0.79 wt%, and the amount of the liquid phase gradually increased with increasing temperature, and reached a content of 33 wt% at 1600 °C when it was mainly the transformation of CaTiO 3 , Al 2 TiO 5 , and TiO 2. In addition, the elevated temperature was helpful to promote sintering, resulting in larger grain sizes, reduced pore volume (0.0514–0.0133 ml/g) and porosity (33.68%–13.11%), and increased bulk density (2.55–3.32 g/cm3), flexural strength (7.57–36.67 MPa), and compressive strength (24.32–97.03 MPa) of the material. [ABSTRACT FROM AUTHOR]

Abstract When processed conventionally, aluminum-bronze alloys with high mechanical strength require machining after the raw state of fusion, and the waste (chips), if not reused, can cause problems for the environment and costs for the company. Therefore, this article proposes an alternative for recycling aluminum bronze through the new route via Powder Metallurgy (PM), analyzing the resulting microstructure. This study compares the microstructures of the aluminum bronze derived from extraction (the samples received - SR) and the state after the powder metallurgy (PM) process with the addition of vanadium carbides (VC). The study also analyzes the distribution of VC in the microstructure of the PM composite as well as the influence of the TQ30 heat treatment on this composite. For the PM process, aluminum alloy and bronze chips were ground together with vanadium carbide (VC) in a high-energy mill for 50 hours. The powders obtained were pressed uniaxially (400 MPa) to achieve good compaction. The samples were then sintered (900°C/lh), water quenched (900°C/2h), and subjected to treatment according to the TQ30 standard, which, in addition to the previous treatments, also includes tempering at 500°C for 2 hours (ASTM B150/B150M-12 standard). The microstructure observed in the SR samples was martensitic (in needles), with secondary phases dispersed in the matrix. On the other hand, the microstructure of the PM samples showed equiaxed grains of the alpha phase (a), as well as the secondary phases kapa (k) and beta line (β1), in contrast to the needle-shaped microstructure of the conventional melting process.

A device with a controllable atmosphere has been designed and fabricated to sinter metal particles in the manufacturing processes of metallic components (porous or non-porous parts). The device avoids the employment of an expensive controlled atmosphere furnace (a furnace in which it is possible to produce a vacuum or through which a constant flow of highly pure inert gas is maintained to protect the specimen). Metallic powders of pure metals or alloys with sintering temperatures (Ts) up to 1300°C and different forms and particle sizes can be used. The device consists of two chambers (an upper chamber for the atmosphere control and a lower chamber for the sintering processes) which are coupled by a sealed system composed of an O–ring and a clamp. The device is designed to be utilized with any conventional vertical electrical furnace (a furnace without the possibility of producing a vacuum inside or maintaining a constant flow of inert gas inside) and can be operated in three different ways: i) with a vacuum inside, ii) with a static atmosphere of inert gas inside, and iii) with a dynamic atmosphere of inert gas inside.

When metal connecting board of solid oxide electrolysis cell (SOEC) are used for long time in a medium-to-high temperature environment (600～800 ℃), severe surface oxidation increases the internal resistance of the electrolytic cell, and the volatilization of Cr from the metal substrate reduces the electrochemical activity of the electrode. The combined effect of the two leads to severe degradation of the performance of SOEC. In response to the above problems, Mn-Co coating and Mn-Co-La coating were prepared on commercial SUS430 metal substrate by electrophoretic deposition method. Subsequently, with using the process of successively sintering under neutral atmosphere (950 ℃, N2) and oxidizing atmosphere (825 ℃, air) conditions, the strong and dense Mn-Co coatings and Mn-Co-La coatings were obtained. Moreover, the effects of sintering atmosphere and La element doping on coating properties were studied. The morphology, phase composition, element distribution and area specific resistance of the coatings were characterized by scanning electron microscope, X-ray diffractometer, energy spectrometer and four-probe resistivity tester, respectively. Results showed that the coating prepared by electrophoretic co-deposition doping with trace amounts of nano-La2O3 had more uniform and refined grains, which effectively inhibited the overflow of Fe-Cr from the substrate during high-temperature N2 sintering. The results of the 300 h oxidation cycle test at 750 ℃ indicated that compared with the substrate, the sintering process proposed in this work was beneficial to improving the anti-oxidation performance of the coating, and the La-doped coating possessed better performance. Furthermore, the doping of La element effectively slowed down the volatilization of Cr in the substrate, which made the area specific resistance lower and more stable, and improved the high-temperature oxidation resistance of the Mn-Co spinel coating.

Flexible electronics have revolutionized the field by overcoming the rigid limitations of traditional devices, offering superior flexibility and adaptability. Conductive ink performance is crucial, directly impacting the stability of flexible electronics. While metal filler-based inks exhibit excellent conductivity, they often lack mechanical stability. To address this challenge, we present a novel conductive ink utilizing a ternary composite filler system: liquid metal and two micron-sized silver morphologies (particles and flakes). We systematically investigated the influence of filler type, mass ratio, and sintering process parameters on the composite ink’s conductivity and mechanical stability. Our results demonstrate that flexible wires fabricated with the liquid metal/micron silver particle/micron silver flake composite filler exhibit remarkable conductivity and exceptional bending stability. Interestingly, increasing the liquid metal content results in a trade-off, compromising conductivity while enhancing mechanical performance. After enduring 5000 bending cycles, the resistance change in wires formulated with a 4:1 mass ratio of micron silver particles to flakes is only half that of wires with a 1:1 ratio. This study further investigates the mechanism governing resistance variations during flexible wire bending. Additionally, we observed a positive correlation between sintering temperature and pressure with the conductivity of flexible wires. The significance of the sintering parameters on conductivity follows a descending order: sintering temperature, sintering pressure, and sintering time. Finally, we demonstrate the practical application of this technology by integrating the composite ink-based flexible wires with conductive polymer-based strain sensors. This combination successfully achieved the detection of human movements, including finger and wrist bending.

The tuning of the properties of MgAl2O4-based materials has aroused great attention in the field of engineering technology. Along these lines, magnesia and alumina were used as raw materials to prepare spinel by the solid-phase sintering method at 1500–1600 °C. Particularly, the impacts of the different MgO/Al2O3 molar ratios on the microstructural densification, sintering process and mechanical property of the fabricated materials were systematically studied. The results showed that the stoichiometric spinel with the highest concentration of ion diffusion possessed the best densification. And the magnesium-rich spinel displayed the better densification following with the formation of solid-solution, while the aluminum-rich spinel exhibited the worst ability in forming the solid-solution. Moreover, the different molar ratios changed the microstructure of the spinel, which induced the optimal sintering temperature of stoichiometric spinel to be at least 50 °C below that of the others. Specifically, in stoichiometric spinel, spinel grains grew up and formed obvious structure, which made the sintering process arrive at the end point and made the performance reach the best. Specifically, the flexural strength was 112.62 MPa and apparent porosity was 0.44%. However, no grown or developed spinel grains were observed for magnesium-rich/aluminum-rich spinels, which delayed the sintering process.

The Th 1- x Sc x O 2- x /2 (0 ≤ x ≤ 0.1) ceramic system with high density was originally prepared via a co-precipitation route and simple sintering method. XRD analysis indicates that the Th 1- x Sc x O 2- x /2 ceramics exhibited a single cubic fluorite structure and a slight increase of cell parameters. SEM images show that Sc doping contributed a decreasing pores and more uniform grain distribution. The calculated relative densities could reach up to a value higher than 99.0% for x = 0.01 during the isothermal process while the maximum actual relative density was only about 77.4% during the non-isothermal sintering process. And the analysis of grain growth kinetics demonstrates that Th 1- x Sc x O 2- x /2 was a solid solution with a high solubility of Sc for x = 0.01 and a low solubility of Sc for both x = 0.05 and x = 0.1, which resulted in a strongly slow grain growth for x = 0.1 due to the solute drag effect. The sintering mechanism investigation also illustrates that low amount (x = 0.01) of Sc doping could significantly enhance the densification sintering of ThO 2 -based ceramics and reduce the sintering temperature by nearly 150 °C. Such strategy has issued the bottleneck problem existed in the densification sintering of ThO 2 -based ceramics at a lower temperature without any other special sintering atmosphere, which even could be applicable for other ceramics difficult to sinter. [ABSTRACT FROM AUTHOR]

Additive manufacturing technology (especially stereolithography) is an effective manufacturing to solve ceramic materials with complex structure difficultly due to their inherent brittleness and hardness, which are applied in electrostatic chuck, vortex generators, and catalyst carriers. In present reports, Al2O3 ceramics via stereolithography mostly focused on the rheology of paste and preparation of part. And there is limited research on the high performance for Al2O3 via stereolithography which can meet the industrial application with complex structure. In this study, high performance of Al2O3 ceramics are fabricated and illuminate relationship between material composition, dispersant, sintering process, microstructure, and mechanical properties in detail. To improve the densification and performance of Al2O3 ceramic, introduction of different particle sizes, the type and content of dispersant had been studied to get the higher powder accumulation and solid loading. Besides, the sintering temperature and holding time were investigated. Finally, when the composition of 5 μm, 3 μm, and 1 μm is 40 wt%, 30 wt%, and 30 wt%, the slurry of Al2O3 with 50 vol% was prepared and specimens sintered at 1650 °C for a holding time of 4 h has a flexural strength of 482 MPa and apparent porosity of 0.06%. [ABSTRACT FROM AUTHOR]

The grain size and phase structure uniformity of europium barium copper oxide (EBCO) superconducting targets would affect the superconducting properties of sputtered film. A uniformly dispersed EBCO slurry was used to prepare high-density green EBCO compacts using slip casting. The effects of milling time and slurry pH on EBCO slurries were studied. Based on the shrinkage data of the EBCO superconducting targets, the densification process was estimated and the apparent activation energy was calculated. The effects of the sintering process on the microstructure and phase composition of EBCO superconducting targets were investigated using scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). When the sintering temperature was 950–1050 °C, the EBCO superconducting target comprised EuBa 2 Cu 3 O 7 and CuO, where a new phase Eu 2 BaCuO 5 formed at a sintering temperature of 1100 °C. The Tc and ΔT of the EBCO superconducting target sintered at 950 °C for 30 h were 91.18 K and 2.35 K. [ABSTRACT FROM AUTHOR]

The process of sintering involves applying pressure and heat to the materials without melting them in order to fuse the particles together into a solid mass. The fusion between the particle are also known as interparticles necking which plays an important role in producing high-density products. Increasing in necking size between particles will allow the formation of smaller pore sizes which help to produce stronger and higher hardness materials. The necking also plays an essential role in producing high porosity products that are commonly used for medical applications which still required high tensile value and hardness. For this, proper process parameters were required to produce larger necking growth. To get a better understanding of this matter, the effect of powder and processing parameters will be reviewed in this article. The parameters for different processes such as conventional sintering, microwave sintering, selective laser melting, and others will be discussed in this paper as well.

This research presents the effects of sintering process and clay composition on the physico-mechanical properties of ceramics from the fifth and fourth millennium BC (6950 ± 280 to 5040 ± 220 TL dating). The combined multiscale mercury intrusion porosimetry (MIP) revealed the increase of round cryptopores and ultramicropores in a range of 0.01–0.1 μm and 0.1–5 μm respectively, closely linked to vitrified glassy connections and bonding between particles and the partial melting of phyllosilicates with different sizes of bubbles at 950 °C. Cold crushing strength (CCS) of the ceramics, containing high calcite and phyllosilicate mineral exhibited a lower strength value from 6.24 to 6.31 MPa at ∼750–800 °C due to the increase in crack porosity area with high interconnectivity and internal stresses. However, the ceramics with a well glassy network show a higher strength value of 16.5Mpa, contributing to sustainable ceramic materials with a uniform cross-section >900 °C and minimal shrinkage for conservation treatment.

In order to optimize the sintering process of gneiss tailings sintered bricks. Using gneiss tailings as main raw material, and added suitable amount of clay to prepare sintered brick, Box-Behnken response surface method was used to create the quadratic regression model between impact factor and response value. Subsequently, the effect on 4 process parameter interaction, like sintering temperature, clay content, molding moisture and particle size, and compressive strength of gneiss tailings sintered brick were investigated, respectively. The sintering process was optimized. The results show that the optimal process parameters of sintered bricks are as follows: clay content 35%, sintering temperature 1 050 ℃, particle size 0. 3 mm, 10% water content. Under the optimal process, the compressive strength of the sintered brick prepared in the laboratory test is 21. 57 MPa, which meets the MU 20 standard in Sintered Ordinary Brick(GB/ T 5101—2017). The sintered bricks prepared at sintering temperature of 1 050 ℃, 10% water content, 0. 3 mm particle size and different clay content were characterized by X-ray diffractionand scanning electron microscope. The results are consistent with the optimal process obtained by response surface method. The combination of sintering parameters can provide theoretical guidance for preparing sintered bricks with high quality performance. [ABSTRACT FROM AUTHOR]

The waste residue (ER) obtained by the mutual treatment of electrolytic manganese residue and red mud. ER is a kind of silicon and aluminum waste residue with low pollution. In order to alleviate the shortage of silicon-aluminum raw materials in ceramic bricks industry. In this paper, ER is used as a part of silicon-aluminum raw material to prepare building ceramic bricks. The results show that the impurity ions (Fe3+, Na+, K+, etc.) in ER can promote the formation of liquid phase during the calcination process. This makes the ceramic bricks can be successfully fired at 1150 °C. The mineral composition of ceramic bricks prepared by ER is anorthite, quartz, corundum, mullite and glass phase, and the corresponding contents are 40.31 wt%, 2.48 wt%, 6.81 wt%, 2.58 wt% and 35.07 wt%, respectively. The layer stacking of plate anorthite is closely combined with the corundum to form a microscopic block. The rod-like mullite is interspersed in the microscopic block to form a skeleton structure. This microstructure makes the mechanical properties of the ceramic bricks superior, and the compressive strength is 138.2 MPa. The sintering process of ceramic bricks prepared by ER can be divided into four stages. Stage 1 (25 °C–200 °C) mainly involved the removal of free water and crystal water and the decomposition of part of AlO(OH) into γ-Al 2 O 3 , the corresponding kinetic mechanism is phase boundary chemical second-order reaction mechanism. Stage 2 (200 °C–400 °C) mainly involved the residual AlO(OH) decomposed into γ-Al 2 O 3 , the corresponding kinetic mechanism is phase boundary–controlled reaction and one-dimensional movement mechanism. Stage 3 (400 °C–900 °C) mainly involved the γ-Al 2 O 3 transformed into α-Al 2 O 3 , CaCO 3 and CaSO 4 decompose into CaO, and CaO reacts with SiO 2 and α-Al 2 O 3 to form (Ca,Na)(Al,Si) 4 O 8 and CaAl 2 Si 2 O 8 , the corresponding kinetic mechanism is random nucleation and growth mechanism. Stage 4 (900 °C–1200 °C) mainly involved the melting of (Ca,Na)(Al,Si) 4 O 8 , and the continuous formation of CaAl 2 Si 2 O 8 , Ca(Al, Fe) 12 O 19 and mullite, the corresponding kinetic mechanism is Mampel power law exponential form nucleation reaction mechanism. [ABSTRACT FROM AUTHOR]

In this study, characteristic changes of Al-xCu alloys produced by the powder metallurgy method in critical transformation regions of binary Al-Cu phase diagram were investigated. In this framework, Al-xCu alloys with a content of 5-15-25-33-45 wt.% Cu, which would enable the formation of hypo-eutectic, eutectic, and hyper-eutectic regions, were prepared. The prepared powders were converted into a green compact form by compressing at a 600 MPa pressure ratio. The obtained green samples were placed in the sintering die and sintered in accordance with the critical transformation temperatures determined in the binary phase diagram. Once the sintering process was completed, the samples in the hot die were compressed at a pressure ratio of 5 MPa and cooled with air. As a result of the microstructural examinations on the produced samples, it was observed that partial liquefaction occurred in the Cu particles due to the increase in the Cu content of the alloy and the amount of CuAl2 intermetallic compound increased accordingly. In this context, as the Cu content of Al-xCu alloys increased, the microhardness and wear resistance values increased; however, the ductility, compressive strength and electrical conductivity values decreased. [ABSTRACT FROM AUTHOR]

NiAl-based composites were fabricated in-situ using vacuum hot-press sintering technology. The Ti3AlC2, TiC and Ti3Al were formed during the sintering process, and the intensity of peaks grow higher with the addition of Al, Ti and C powder contents, respectively. The microhardness of the composites was significantly improved by adding these powders and gradually increased with the incremental content of Al, Ti and C powders. Meanwhile, the tribological properties of the composites at high temperature were also improved. The worn surface formed during the tribo-oxidation reactions and produced the glaze film in the high-temperature friction process, which could improve the composites' tribological properties. The TiO2 and Al2O3 phases were observed on the worn surface after the friction test, which could act as a high-temperature lubricant and improve the composites’ tribological properties.

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Aqueous zinc batteries with low cost and inherent safety are considered to be the most promising energy storage devices. However, they suffer from poor cycling stability and low coulombic efficiencies caused by the adverse zinc dendrites on the anodes during the discharging/charging processes. Chitosan is a kind of natural amino polysaccharide, which is rich in nitrogen and carbon. When sintered at high temperatures, carbon membranes have been achieved with excellent conductivity and graphitization degree, which could enhance the ability to induce zinc ion uniform deposition to some extent. In this work, a type of carbon membrane using chitosan as raw materials has been fabricated by sintering, and then assembled as the protect layers in aqueous zinc batteries. The results show that the samples could retain smoother surfaces when adopting the sintering temperature of 800°C, and the assembled batteries are able to achieve about 700 h at a current density of 0.25 mA·cm−2, which is far longer than those of the similar batteries without any carbon membranes. [ABSTRACT FROM AUTHOR]

The sintering process, which mainly determines the formation of the structure and properties of the material, is considered. The essence of the sintering process and its stages are considered. The formation and growth of interparticle contacts during sintering due to the mass transfer of the substance is shown, which becomes possible due to the high mobility of atoms during heating. The mechanism of spheroidization of pores and particles is considered. [ABSTRACT FROM AUTHOR]