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Waste management and recycling have led to numerous studies on particleboard production. This study attempted to use milled corncob (MCC) and waste ceramic tiles (WCTs) to produce particleboard. The MCC (100−70 wt.%) and WCT (0–30 wt.%) were mixed at different ratios, mixed and compressed at a pressure of 0.25 MPa using urea formaldehyde (UF) resin as adhesive. The physicomechanical and thermal properties of the particleboards produced were investigated. The physical properties (bulk density, water absorption, and thickness swelling) improved with composite particleboard compared to the 100% MCC particleboard. The increase in WCT yielded improved density and lowered the particleboard's water absorption and thickness swelling. The mechanical tests showed that MOE values were below the recommended standard, which makes them unsuitable for structural use. However, MOR revealed values above the recommended standard. The thermal conductivity of the particleboards was reduced with increased WCT, and the required standard was found to be met. Hence, the particleboards produced are found helpful as thermal wall insulators. Based on the experiments done, sample R7 (70% MCC and 30% WCT) was considered the most preferable since it achieved the most preferable physicomechanical and thermal conductivity performance. The particleboards produced are recommended for wall partitioning and other internal and external purposes. [ABSTRACT FROM AUTHOR]

Hybridization of natural fibers with ceramic materials for reinforcing composites allows the optimization of the properties of these materials. For this reason, the present study aims to investigate physical, mechanical, water absorption, swelling and thermal properties as well as morphological characteristics of a hybrid Paederia foetida fibers–alumina powder (PFs–Al2O3)‐reinforced epoxy composite. Epoxy resin served as the matrix, while PFs and Al2O3 were employed as reinforcement. Five types of composites were fabricated using the hot‐pressing technique. The corresponding ratios of PFs:Al2O3 volume fractions (%) considered here were 0:40 (SFA), 10:30 (SFB), 20:20 (SFC), 30:10 (SFD) and 40:0 (SFE). The results reveal that the density of the hybrid PFs–Al2O3 composites decreased for increasing volume fractions of PFs: from 2.173 g cm−3 of SFA to 1.042 g cm−3 of SFE. The highest values of tensile strength (i.e. 49.085 MPa), tensile elastic modulus (i.e. 1.431 GPa) and impact strength (24 kJ m−2) were obtained for the SFD composite material with 30% volume fraction of PFs and 10% volume fraction of Al2O3: this happened because interface bonds between PFs, Al2O3 and epoxy phases achieved their optimal configuration. Overall, mechanical properties of the hybrid PFs–Al2O3‐reinforced epoxy composites were superior to those of composites reinforced only by PF fibers or only by Al2O3. Water absorption and swellability reached their maximum values at the steady state occurring after tested samples remained immersed in water for 820 h. The SFE composite reinforced only by PFs presented the highest water absorption and swelling (i.e. 6.034% and 5.81%, respectively) while for all other hybrid composites (SFD, SFC and SFB) these two quantities remained below 5%. Density and volume fraction of voids of hybrid PFs–Al2O3‐reinforced composites were consistent with the corresponding properties of the composites reinforced only by Al2O3 or PFs. SFD was also the most thermally stable material. Scanning electron microscopy observations of fractured surfaces indicated that the microstructure of the PFs–Al2O3‐reinforced epoxy composites presents several voids, fiber pullouts and transverse fibers, which together optimize the mechanical response of the composite material. Remarkably, the SFD composite material was highly competitive with the most recently developed hybrid composites employing natural reinforcements. © 2024 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

This paper investigates the vibration characteristics of a sandwich nanosensor plate composed of piezoelectric materials, specifically barium and cobalt, in the upper and lower layers, and a core material consisting of either ceramic (silicon nitride) or metal (stainless steel) foams reinforced with graphene (GPRL). The study utilized the novel sinosoidal higher-order deformation theory and nonlocal strain gradient elasticity theory. The equations of motion for nanosensor sandwich graphene were derived using Hamilton's principle, considering the thermal, electroelastic, and magnetostrictive characteristics of the piezomagnetic surface plates. These equations were then solved using the Navier method. The core element of the sandwich nanosensor plate can be represented using three distinct foam variants: a uniform foam model, as well as two symmetric foam models. The investigation focused on analyzing the dimensionless fundamental natural frequencies of the sandwich nanosensor plate. This analysis considered the influence of three distinct foam types, the volumetric graphene ratio, temperature variation, nonlocal parameters, porosity ratio, electric and magnetic potential, as well as spring and shear viscoelastic support. Furthermore, an analysis was conducted on the impact of the metal and ceramic composition of the central section of the sandwich nanosensor plate on its dimensionless fundamental natural frequencies. In this context, the use of ceramic as the central material results in a mean enhancement of 33% in the fundamental natural frequencies. In contrast, the incorporation of graphene into the core material results in an average enhancement of 27%. The thermomechanical vibration behavior of the nanosensor plate reveals that the presence of graphene-supported foam and a viscoelastic support structure in the core layer leads to an increase in thermal resistance. This increase is dependent on factors such as the ratio of graphene, porosity ratio of the foam, and parameters of the viscoelastic support. Metal foam or ceramic foam has been found to enhance thermal resistance when compared to solid metal or ceramic core materials. The analysis results showed that it is important to take into account the temperature-dependent thermal properties of barium and cobalt, which are piezo-electromagnetic materials, and the core layer materials ceramics and metal, as well as the graphene used to strengthen the core. The research is anticipated to generate valuable findings regarding the advancement and utilization of nanosensors, transducers, and nano-electromechanical systems engineered for operation in high-temperature environments. [ABSTRACT FROM AUTHOR]

Microwave foaming was used for the first time to rapidly fabricate the metakaolin-based porous geopolymers. Mechanical, thermal, and microstructural (optical and scanning electron microscope) investigations coupled with X-ray diffraction, Fourier-transform infrared spectroscopy, and nuclear magnetic resonance techniques were conducted to characterize the obtained foams. High porosity metakaolin-based porous geopolymers could be obtained at 4 min of foaming/curing. The effect of the sodium silicate solution content on the total porosity as well as the mechanical and thermal properties was investigated. The total porosity decreased firstly and then increased in the range of ∼74 to ∼84 vol% with the increase of Na 2 SiO 3 content. The foams with 47.7 wt% Na 2 SiO 3 exhibited the lowest thermal conductivity (0.104 W/mK) and the highest total porosity (83.2 vol%). The fabrication time, mechanical, and thermal properties were compared with those of foams obtained by the conventional direct foaming method. With this approach, the preparation time can be greatly reduced, and the compressive strength (1.89–2.04 MPa) and thermal conductivity (0.104–0.155 W/mK) of the materials obtained were not inferior to similar components obtained by other foaming routes. The rapidly obtained porous geopolymers with high porosity and high strength as well as low thermal conductivity can be employed as thermal insulation materials and ceramic precursors. [Display omitted] • An effective strategy for highly porous geopolymers (PGs) is developed. • Metakaolin-based PGs were fabricated within 4 min by microwave foaming. • The properties can be tailored by the sodium silicate solution addition. • The PG can be used as thermal insulation material and ceramics precursor. [ABSTRACT FROM AUTHOR]

In this paper, we investigate a metal composite prepared using a one-step pressing method, where Al–Si alloy acts as the phase change materials (PCMs) and Al 2 O 3 /AlN serve as the structural support materials. The alloy formation and PCM composite preparation are synthesized in a single step. The study aims to characterize the microstructure, thermodynamic, and thermal properties of the composite material. To assess the heat storage properties of the prepared composite PCMs at temperatures higher than 600 °C, a high-temperature test system is established using a high-frequency induction heater. Additionally, we explore how to improve the issue of liquid leakage under high-temperature conditions. The results demonstrate that Al 2 O 3 and AlN (ceramic materials) exhibit excellent chemical compatibility with Al–Si composite PCMs. After sintering, the ceramic materials form a strong bond with Al–Si, effectively retaining the liquid phase of Al–Si alloy within the composite material. Consequently, the Al–Si composite PCMs do not exhibit high-temperature liquid leakage under elevated conditions. Both Al 2 O 3 /Al–Si and AlN/Al–Si composites possess favorable high temperature heat storage properties. The phase change enthalpy of Al 2 O 3 /Al–Si composite reaches 400 kJ/kg, with a thermal conductivity of 36 W/(m·K). Similarly, the AlN/Al–Si composite achieves a phase change enthalpy of 404 kJ/kg and a thermal conductivity of 43 W/(m·K). Both composites fulfill the requirements for high-temperature heat storage applications. • Prepare Al–Si alloy at a low temperature of 750 °C. • Choose AlN as a novel ceramic material to enhance thermal properties for Al–Si alloy. • Employ in situ XRD to monitor crystal changes, unraveling synthesis mechanism. • High-temperature heat storage performance has been evaluated at 1000 °C. [ABSTRACT FROM AUTHOR]

In this paper, tin-phosphate amorphous glass and nano-crystallized ceramic materials were synthesized by sol-gel methods and heat treated at 400 °C with the composition of x SnO 2 − (100- x)P 2 O 5 (x SnP: ' x ' from 40 to 90 mol%). The electrical and thermal properties of tin-phosphate materials were investigated by electrical impedance spectroscopy (EIS) and thermogravimetry – differential thermal analysis – mass spectroscopy (TG–DTA–MS). Moreover, the local structure of x SnP was characterized by 119Sn-Mössbauer and magic angle spinning (MAS) 31P NMR spectroscopies. Homogeneous glasses were obtained for x SnP with ' x ' from 50 to 80, while Sn(HPO 4), SnO 2 , and Sn 3 (PO 4) 2 nanoparticles formed in 40SnP and 90SnP compositions, respectively. The nano-crystallized 40SnP and 90SnP samples showed large electrical conductivity (σ) of 2.02×10−5 and 1.04×10−4 S cm−1 due to the conductive crystalline phases of SnP 2 O 7 and defective SnO 2 , respectively. The lower σ of about 10−8 S cm−1 were recorded for x SnP with ' x ' from 50 to 80 owing to the decomposition of the 3D network built by phosphate tetrahedrons. 119Sn-Mössbauer spectra proved the growing number of SnIVO 6 units, which do not contribute to the rise of electrical conductivity. On the other hand, larger σ values of 1.79×10−4 and 6.4×10−3 S cm−1 were confirmed for 40SnP and 90SnP samples after heat treatment, resulting in partial reduction of SnIV to SnII and growing of the 3D network structure by PO 4 3−. It is concluded that highly electrically conductive x SnP samples can be synthesized by the sol-gel method followed by slow heat treatment. In addition, the battery evaluation was performed of x SnP samples as cathode and anode in a sodium-ion battery. The highest initial capacity recorded for 90SnP nano-crystallized ceramic at 37.97 mAh g−1 under a current rate of 20 mA g−1 with capacity retention (%) of 48.15% after 100 cycles as a cathode material. The anode test showed that the 40SnP nano-crystallized ceramic has the largest initial capacity of 375 mAh g−1 and after heat treatment 50SnP glass significantly increased to 425 mAh g−1 compared with 186 mAh g−1 before heat treatment. Also, the heat treatment effect on the initial capacity of 90SnP nano-crystallized ceramic with observation largest value of 470 mAh g−1. These results open the way to maybe applying these glass and nano-crystallized ceramic materials in all-solid-state batteries. • The x SnO 2 −(90− x)P 2 O 5 glass was successfully prepared with a wider chemical composition of SnO 2 concentration from 50 to 80 mol% by the sol-gel method. • The 40SnP and 90SnP samples exhibited notably high σ 's of 1.79×10−4 and 6.40×10−3 Scm−1 attributed to their elevated levels of proton conductivity. • 90SnP as cathode demonstrated the highest initial capacity, achieving 37.97 mAh g−1 and maintaining a capacity retention of 48.15% after 100 cycles. • 40SnP and 90SnP exhibited a large initial capacity of 375 mAh g−1 and 470 mAh g−1, as anode materials in SIBs. [ABSTRACT FROM AUTHOR]

The current study introduces porous ceramic materials fabricated from cenospheres through spark plasma sintering. The investigation delves into the impact of sintering temperature, mould diameter (20 and 30 mm), and cenosphere size on the resulting material properties. Notably, sample shrinkage initiates at 900 °C and demonstrates an upward trend with temperature escalation, while a larger mould diameter contributes to sample shrinkage. Elevated sintering temperature leads to increased apparent density across various sample series, such as CS 63–150 µm in a 20 mm mould (0.97 to 2.3 g/cm³ at 1050–1300 °C), CS 150–250 µm in a 20 mm mould (0.93 to 1.96 g/cm³ at 1050–1200 °C), and others in different mould sizes. Total porosity decreases from 61.5 % to 3.9 % with a rising sintering temperature (1050 to 1250 °C), while open porosity starts decreasing at lower temperatures. Closed porosity peaks in samples sintered at 1150 °C. Furthermore, an increase in sintering temperature from 1050 to 1300 °C boosts the compressive strength of CS 63–150 samples in a 20 mm mould from 11 MPa to 312 MPa. These findings align with the Rice model, illustrating an exponential relationship between compressive strength, material porosity, and fully dense material compressive strength. [ABSTRACT FROM AUTHOR]

The increase in operating temperature contributes to improving the performance and fuel utilization efficiency of gas turbines. However, it also places thermal barrier coatings (TBCs) in a more demanding working environment, requiring higher sintering resistance and better mechanical properties. In the present study, HfO2 was introduced into the dual‐phase LaYbZr2O7 system as a doping oxide to form the LaYb(HfxZr1−x)2O7 system. The research concentrated on its phase composition, mechanical properties, and thermophysical properties. The results show that substituting Hf for Zr does not alter the dual‐phase structure of the system. The mutual inhibition between the two phases and the inherent material‐binding capability of Hf further reduce the grain size compared to pure LYZO. Additionally, the presence of Hf reduces the tendency of Frenkel defect formation and cation migration frequency, effectively inhibiting ion diffusion and thereby suppressing the densification and shrinkage trends of the material. The system retains relatively high hardness, fracture toughness, and low elastic modulus of the LYZO matrix, with a decrease in thermal conductivity and an increase in infrared reflectivity. These results suggest that Hf doping enhances the sintering resistance of LYZO material, making them promising for high‐temperature TBCs. Our study presents a viable approach to enhance the sintering resistance of LYZO, and this methodology can be extrapolated to other rare‐earth zirconates. [ABSTRACT FROM AUTHOR]

Ceramic fibers are an important thermal insulation material that are not only widely used in extreme conditions, but also play an important role in energy conservation and energy efficiency for sustainable development. However, the practical application of conventional ceramic fibers has a high thermal conductivity in high-temperature environments, which hinders their widespread application. Here, a novel lamellar structured porous SiTiOC/C composite ceramic materials was designed and prepared with excellent thermal insulating properties. The unique microstructure endowed the porous SiTiOC/C composite ceramic materials with a high IR refractive index (93.81%) and an ultra-low thermal conductivity (0.0562 W·m−1 K−1 at 600 ℃). In addition, the porous SiTiOC/C composite ceramic materials not only exhibited excellent mechanical properties (4.46 MPa at 800 ℃), but also demonstrated impressive oxidation resistance and thermal stability. In summary, the proposed porous SiTiOC/C composite ceramic materials provide a reference for the development of high-temperature insulation with good mechanical properties. [ABSTRACT FROM AUTHOR]

As the international situation continues to change and conflicts in various countries intensify, improving national defense forces is a necessary condition to ensure the stable development of the country, and bulletproof armor is a key part of it. Pressureless sintered silicon carbide ceramics have been widely used in the field of bulletproof armor because of its simple preparation process and excellent mechanical properties of low density, high hardness and high strength. The hardness and fracture toughness of pressureless sintered silicon carbide bulletproof ceramics directly determine the quality of bulletproof performance. Promoting sintering densification and multi-phase composite sintering are the key ways to improve the hardness and fracture toughness of pressureless sintered silicon carbide ceramics. This sturdy summarizes the research progress of pressureless sintered silicon carbide bulletproof ceramic materials in recent years, focusing on the sintering aids, toughening methods, composite form of pressureless sintered silicon carbide bulletproof ceramic materials. [ABSTRACT FROM AUTHOR]

Improving fracture toughness, electrical conductivity, and biocompatibility has consistently presented challenges in the development of artificial bone replacement materials. This paper presents a new strategy for creating high-performance, multifunctional composite ceramic materials by doping graphene oxide (GO), which is known to induce osteoblast differentiation and enhance cell adhesion and proliferation into barium calcium zirconate titanate (BCZT) ceramics that already exhibit good mechanical properties, piezoelectric effects, and low cytotoxicity. Using fast hot-pressed sintering under vacuum conditions, (1 − x)(Ba0.85Ca0.15Zr0.1Ti0.9)O3−xGO (0.2 mol% ≤ x ≤ 0.5 mol%) composite piezoelectric ceramics were successfully synthesized. Experimental results revealed that these composite ceramics exhibited high piezoelectric properties (d33 = 18 pC/N, kp = 62%) and microhardness (173.76 HV0.5), meeting the standards for artificial bone substitutes. Furthermore, the incorporation of graphene oxide significantly reduced the water contact angle and enhanced their wettability. Cell viability tests using Cell Counting Kit-8, alkaline phosphatase staining, and DAPI staining demonstrated that the GO/BCZT composite ceramics were non-cytotoxic and effectively promoted cell proliferation and growth, indicating excellent biocompatibility. Consequently, with their superior mechanical properties, piezoelectric performance, and biocompatibility, GO/BCZT composite ceramics show extensive potential for application in bone defect repair. [ABSTRACT FROM AUTHOR]

Ceramic fibers have the advantages of high temperature resistance, light weight, favorable chemical stability and superior mechanical vibration resistance, which make them widely used in aerospace, energy, metallurgy, construction, personal protection and other thermal protection fields. Further refinement of the diameter of conventional ceramic fibers to microns or nanometers could further improve their thermal insulation performance and realize the transition from brittleness to flexibility. Processing traditional two-dimensional (2D) ceramic fiber membranes into three-dimensional (3D) ceramic fiber aerogels could further increase porosity, reduce bulk density, and reduce solid heat conduction, thereby improving thermal insulation performance and expanding application areas. Here, a comprehensive review of the newly emerging 2D ceramic micro-nanofiber membranes and 3D ceramic micro-nanofiber aerogels is demonstrated, starting from the presentation of the thermal insulation mechanism of ceramic fibers, followed by the summary of 2D ceramic micro-nanofiber membranes according to different types, and then the generalization of the construction strategies for 3D ceramic micro-nanofiber aerogels. Finally, the current challenges, possible solutions, and future prospects of ceramic micro-nanofiber materials are comprehensively discussed. We anticipate that this review could provide some valuable insights for the future development of ceramic micro-nanofiber materials for high temperature thermal insulation. [ABSTRACT FROM AUTHOR]

Magnesium matrix composites are essential lightweight metal matrix composites, following aluminum matrix composites, with outstanding application prospects in automotive, aerospace lightweight and biomedical materials because of their high specific strength, low density and specific stiffness, good casting performance and rich resources. However, the inherent low plasticity and poor fatigue resistance of magnesium hamper its further application to a certain extent. Many researchers have tried many strengthening methods to improve the properties of magnesium alloys, while the relationship between wear resistance and plasticity still needs to be further improved. The nanoparticles added exhibit a good strengthening effect, especially the ceramic nanoparticles. Nanoparticle-reinforced magnesium matrix composites not only exhibit a high impact toughness, but also maintain the high strength and wear resistance of ceramic materials, effectively balancing the restriction between the strength and toughness. Therefore, this work aims to provide a review of the state of the art of research on the matrix, reinforcement, design, properties and potential applications of nano-reinforced phase-reinforced magnesium matrix composites (especially ceramic nanoparticle-reinforced ones). The conventional and potential matrices for the fabrication of magnesium matrix composites are introduced. The classification and influence of ceramic reinforcements are assessed, and the factors influencing interface bonding strength between reinforcements and matrix, regulation and design, performance and application are analyzed. Finally, the scope of future research in this field is discussed. [ABSTRACT FROM AUTHOR]

Materials offering high energy density are currently desired to meet the increasing demand for energy storage applications, such as pulsed power devices, electric vehicles, high-frequency inverters, and so on. Particularly, ceramic-based dielectric materials have received significant attention for energy storage capacitor applications due to their outstanding properties of high power density, fast charge–discharge capabilities, and excellent temperature stability relative to batteries, electrochemical capacitors, and dielectric polymers. In this paper, we present fundamental concepts for energy storage in dielectrics, key parameters, and influence factors to enhance the energy storage performance, and we also summarize the recent progress of dielectrics, such as bulk ceramics (linear dielectrics, ferroelectrics, relaxor ferroelectrics, and anti-ferroelectrics), ceramic films, and multilayer ceramic capacitors. In addition, various strategies, such as chemical modification, grain refinement/microstructure, defect engineering, phase, local structure, domain evolution, layer thickness, stability, and electrical homogeneity, are focused on the structure–property relationship on the multiscale, which has been thoroughly addressed. Moreover, this review addresses the challenges and opportunities for future dielectric materials in energy storage capacitor applications. Overall, this review provides readers with a deeper understanding of the chemical composition, physical properties, and energy storage performance in this field of energy storage ceramic materials. [ABSTRACT FROM AUTHOR]

High-entropy carbide ceramic materials exhibited excellent thermal and mechanical properties, making them highly sought after in high-temperature applications. However, the oxidation resistance of high-entropy carbide ceramic needed to be further improved. This work unraveled the oxidation behavior and mechanism of high-entropy carbide ceramic by introducing the Cr 3 C 2. The results indicated that the oxidation rate of (TiZrTaNbCr)C initially decreased with temperature up to 900 °C, followed by an increased with further temperature rise up to 1100 °C. At 800 and 900 °C, the parabolic oxidation rate constants were 0.70 and 0.17 mg2cm−4min−1, respectively. And the minimum thickness of oxidized layer was 60 µm at 900 °C for 120 min. This unusual phenomenon suggested the formation of different oxidation products. Specifically, the CrNbO 4 and Nb 2 Zr 6 O 17 oxide layer were formed at 900 °C, leading to an increased resistance to oxygen diffusion. Subsequently, loose oxidation products of Nb 2 O 5 were formed after 1000 °C, hindering the oxidation resistance. In the current study on oxidation resistance of high entropy carbides, this work showed a competitive performance. Overall, this study illustrated the oxidation mechanism and behavior of (TiZrTaNbCr)C and proposed a new avenue for the design of high-entropy ceramic components. [ABSTRACT FROM AUTHOR]

Lithium-ion (Li-ion) batteries are widely used in high-performance energy storage applications because of their high energy density. However, safety concerns related to thermal runaway remain a significant challenge for Li-ion batteries. Electrolyte leakage and dendrite formation can trigger thermal runaway, and these factors typically damage traditional polyethylene (PE) separators. Consequently, these separators struggle under extreme conditions and fail to control dendrite growth. In this study, we proposed a solution by coating PE separators with graphene oxide (GO) layers. GO, as a ceramic material, provides superior thermal and mechanical stability compared with polymers. Moreover, GO-coated PE separators (GO-S) do not compromise the advantages of PE separators and effectively manage dendrite growth. In this study, the as-prepared GO-S exhibits excellent electrochemical properties in terms of high ionic conductivity, suppression of Li dendrite growth during charge/discharge process, and long-term cyclability for 7,000 h (3,500 cycles) as well as high thermal stability even after heat treatment of 100°C. Thus, we expect that this research can highlight the potential application of functionalized GO sheets in addressing the thermal and mechanical limitations of polymer-based separators, thereby enhancing the safety and reliability of Li-ion batteries. [ABSTRACT FROM AUTHOR]

The preparation of ceramic materials with complex porous structures through photopolymerization-based 3D printing requires the development of stable and printable slurries. In this study, zirconium acetylacetonate was incorporated into the thiol vinyl organosilicon prepolymer to create a photosensitive Si–Zr–O–C slurry. Regarding the natural bone structures and the Tyson polygon principle, a gradient pore structure was designed and then printed using a digital light processing 3D printer. After printing, the effects of sintering temperatures on the phase composition and structure of Si–Zr–O–C ceramics were systematically investigated. Subsequently, a comparative analysis of structure and properties was performed on sintered samples with different zirconium acetylacetonate contents. The results revealed that the sample containing 30 wt. % zirconium acetylacetonate exhibited a higher compressive strength of 9.70 ± 0.28 MPa and a lower room temperature thermal conductivity of 0.528 W m−1 K−1. This study confirmed the significant potential of using 3D printing technology to prepare Si–Zr–O–C precursor ceramics with a porous structure. [ABSTRACT FROM AUTHOR]

The microstructure is a critical factor governing the functionality of ceramic materials. Meanwhile, microstructural analysis of electron microscopy images of polycrystalline ceramics, which are geometrically complex and composed of countless crystal grains with porosity and secondary phases, has generally been performed manually by human experts. Objective pixel-based analysis (semantic segmentation) with high accuracy is a simple but critical step for quantifying microstructures. In this study, we apply neural network-based semantic segmentation to secondary electron images of polycrystalline ceramics obtained by three-dimensional (3D) imaging. The deep-learning-based models (e.g., fully convolutional network and U-Net) by employing a dataset based on a 3D scanning electron microscopy with a focused ion beam is found to be able to recognize defect structures characteristic of polycrystalline materials in some cases due to artifacts in electron microscopy imaging. Owing to the training images with improved depth accuracy, the accuracy evaluation function, intersection over union (IoU) values, reaches 94.6% for U-Net. These IoU values are among the highest for complex ceramics, where the 3D spatial distribution of phases is difficult to locate from a 2D image. Moreover, we employ the learned model to successfully reconstruct a 3D microstructure consisting of giga-scale voxel data in a few minutes. The resolution of a single voxel is 20 nm, which is higher than that obtained using a typical X-ray computed tomography. These results suggest that deep learning with datasets that learn depth information is essential in 3D microstructural quantifying polycrystalline ceramic materials. Additionally, developing improved segmentation models and datasets will pave the way for data assimilation into operando analysis and numerical simulations of in situ microstructures obtained experimentally and for application to process informatics. [ABSTRACT FROM AUTHOR]

Additive manufacturing technologies collectively refer to a set of layer-wise deposition methods that typically rely on CAD-CAM approaches for obtaining products with a complex shape/geometry and high precision and reliability. If the additive manufacturing of polymers is relatively easy and scalable due to the low temperatures needed to obtain processable inks, using similar technologies to fabricate ceramic products is indeed more challenging and expensive but, on the other hand, allows for obtaining high-quality results that would not be achievable through conventional methods. Furthermore, the implementation of additive manufacturing allows for the addressing of some important concerns related to the environment and sustainability, including the minimization of resource depletion and waste production/disposal. Specifically, additive manufacturing technologies can provide improvements in energy consumption and production costs, besides obtaining less waste material and less CO2 emissions, which are all key points in the context of the circular economy. After providing an overview of the additive manufacturing methods which are specifically applied to ceramics, this review presents the sustainability elements of these processing strategies, with a focus on both current and future benefits. The paucity of specific available studies in the literature—which are included and discussed in this review—suggests that the research on additive manufacturing sustainability in the field of ceramic materials is in the preliminary stage and that more relevant work still deserves to be carried out in the future to explore this fascinating field at the boundary among ceramics science/technology, production engineering and waste management. [ABSTRACT FROM AUTHOR]

The treatment of bone defects has always posed challenges in the field of orthopedics. Scaffolds, as a vital component of bone tissue engineering, offer significant advantages in the research and treatment of clinical bone defects. This study aims to provide an overview of how 3D printing technology is applied in the production of bone repair scaffolds. Depending on the materials used, the 3D-printed scaffolds can be classified into two types: single-component scaffolds and composite scaffolds. We have conducted a comprehensive analysis of material composition, the characteristics of 3D printing, performance, advantages, disadvantages, and applications for each scaffold type. Furthermore, based on the current research status and progress, we offer suggestions for future research in this area. In conclusion, this review acts as a valuable reference for advancing the research in the field of bone repair scaffolds. [ABSTRACT FROM AUTHOR]

Calcium hexaluminate (CA6) porous ceramics were prepared by foaming and pore-forming agent methods, with Al2O3 and calcium aluminate cement (CAC) as raw materials and magnesium aluminum spinel hollow spheres (MASHSs) as pore-forming agent. The effects of the amount of magnesium aluminum spinel hollow sphere on the phase composition, bulk density, apparent porosity, flexural strength, microstructure, and thermal conductivity of CA6-based porous ceramics were systematically studied. The pores of such porous ceramics are mainly formed by the enhanced amount of MASHSs and the generation of CA6 phase. The results demonstrate that with the elevation of MASHSs content, the microstructure of the samples transforms from a uniform distribution of closed pores to an interconnected micro-pore arrangement. Notably, the fracture paths transition from cohesive to interfacial interactions between MASHSs. This intricate interplay culminates in a remarkable outcome – our ceramics exhibit thermal conductivities ranging from 0.210 to 0.451 W/(m/k), an augmented gas permeability of 25.96 × 10−11m2, and exceptional compressive strengths reaching up to 22.3 MPa. Overall, this study provides insights into the influence of MASHSs content on the microstructure and thermal-mechanical properties of porous materials, which may contribute to the development of advanced ceramic materials with tailored properties. [ABSTRACT FROM AUTHOR]

The demand for innovative materials has been a significant driving force in material development in a variety of industries, including automotive, structural, and biomedical. Even though a tremendous amount of research has already been conducted on metallic, polymeric, and ceramic materials, they all have distinct drawbacks when used as mono-materials. This gave rise to the development of nature-inspired sandwich-structured composite materials. The combination of strong metallic skins with soft polymeric cores provides several advantages over mono-materials in terms of weight, damping, and mechanical property tuning. With this in mind, this review focuses on the various aspects of MPM SMs (Metal/polymer/metal Sandwich Materials). The reasons for the improved qualities of MPM SMs have been discussed, as well as the numerous approaches to producing such SMs. This review shows the various possibilities of achieving such SMs in complicated forms via different shaping techniques and intends to highlight the properties of MPM SMs' remarkable qualities, the current trend in this field, and their potential to meet the demands of many industries. [ABSTRACT FROM AUTHOR]

Energy efficient buildings, propulsion components and thermal protection systems require materials with high thermal protective properties. Traditional polymer composites or ceramic materials have limited comprehensive applications because of their poor thermal protective properties or poor processability. Herein, a novel fire resistant and thermally insulating polymer/ceramic hybrid ceramifiable composite was developed based on low temperature sintering principle and foaming on fire strategy. Specifically, the influences of raw materials of low temperature ceramics, such as glass frit, phosphate, etc, on the properties of ceramifiable ethylene-vinyl acetate (EVA) composites were investigated. Its fire resistance and thermal insulation properties were evaluated by simulating different sintering environments. The results show that the ceramifiable composite exhibits the highest improvement in fire resistance because a crystalline phase was formed at high temperatures. Gas evolution from the thermal decomposition of ammonium polyphosphate (APP) and EVA contributes to the formation of the porous structure in ceramic residues. The optimal system can resist above 1000 °C flame for 30 min without disintegration, and the temperature of the unfired side was maintained around 200 °C. The reliability of the strategy was verified by the effective medium theory model. [Display omitted] [ABSTRACT FROM AUTHOR]

Ceramic fiber thread is one of the key components in flexible external thermal insulation blankets, and it has been applied in various fields as a flexible ceramic fibrous material with excellent deformability and high-temperature resistance. However, ceramic fiber threads are often subjected to reciprocating friction motion at specific bending angles, making them highly susceptible to abrade and fracture. Enhancing the abrasion resistance performance of ceramic fiber threads under bending conditions is the future trend and remains a significant challenge. Hence, we design and construct a novel polyurethane-modified coating on the ceramic fiber threads to improve their abrasion resistance performance. The effects of the types and concentrations of modifiers on the microstructure, abrasion resistance property, and tensile property of ceramic fiber threads are systematically investigated. The ceramic fiber threads, after modification with hexamethylene diisocyanate waterborne polyurethane (HDI-WPU) with a concentration of 3%, exhibit excellent abrasion resistance properties. The number of friction cycles at fracture of the modified ceramic fiber thread is more than three times, and the tensile strength is more than one and a half times, that of the original ceramic fiber thread, demonstrating the great potential of the HDI-WPU modifier for enhancing the abrasion resistance performance of ceramic fiber threads. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) is widely used in tissue engineering and other biomedical applications. PLA can be modified with appropriate biocompatible ceramic materials since this would allow tailoring the mechanical properties of the tissues to be engineered. In this study, PLA-based non-woven fibrillar nanocomposites containing nanoparticles of hydroxyapatite (HA), a bioceramic commonly used in bone tissue engineering, were prepared via solution blow spinning (SBS). The compositions of the final materials were selected to study the influence of HA concentration on the structure, morphology, and thermal and mechanical properties. The resulting materials were highly porous and mainly constituted fibers. FTIR analysis did not reveal any specific interactions. The diameters of the fibers varied very little with the composition. For example, slightly thinner fibers were obtained for pure PLA and PLA + 10% HA, with fiber diameters of less than 400 nm, while the thicker fibers were found for PLA + 1% HA, with average diameters of 427 ± 170 nm. The crystallinity and stiffness of the PLA/HA composite increased with the HA content. Further, composites containing PLA fibers with slightly larger diameters were more ductile. Thus, with an appropriate balance between factors, such as the diameter of the solution-blow-spun PLA fibers, HA particle content, and degree of crystallinity, PLA/HA composites may be effectively used in tissue engineering applications. [ABSTRACT FROM AUTHOR]

The current investigation presents porous ceramic materials prepared with cenospheres (CS) by using spark plasma sintering. The impact of sintering temperature, mould diameter (20, 30 and 50 mm) and cenosphere size on the properties of the sintered material was investigated. Shrinkage of the samples during sintering started at 900 °C. Total sample shrinkage during sintering increases with increasing temperature and decreases with increasing mould size; increasing sample sintering temperature increases the apparent density of all sample series CS 63–150 µm in a 20 mm mould from 0.97 to 2.3 g·cm−3 at 1050–1300 °C; in a 30 mm mould, 0.81–1.87 g·cm−3 at 1050–1200 °C; in 50 mm mould, 0.54–0.75 g·cm−3 at 1050–1150 °C; while CS 150–250 µm in a 20 mm mould is 0.93–1.96 g·cm−3 at 1050–1200 °C. Total porosity decreases from 61.5% to 3.9% by increasing sintering temperature from 1050 to 1250 °C, while open porosity reduces at lower temperatures, with closed porosity being highest in samples sintered at 1150 °C. When the sintering temperature increases from 1050 to 1300 °C, the compressive strength of the CS 63–150 samples produced in a 20 mm mould increases from 11 MPa to 312 MPa. These results correlate with the Rice model, which describes an exponential dependence of compressive strength on material porosity and fully dense material compressive strength. [ABSTRACT FROM AUTHOR]

It is known that ceramic–polymer composite materials can be used to manufacture spherical bodies in the category of balls. Since balls are frequently subjected to compression loads, the paper presents some research results on the compression behavior of balls made of ceramic composite materials with a polymer matrix. The mathematical model of the pressure variation inside the balls highlights the existence of maximum values in the areas of contact with other parts. Experimental research was carried out on balls with a diameter of 20 mm, manufactured by 3D printing from four ceramic–polymer composite materials with a polymer matrix: pottery clay, terracotta, concrete, and granite. The same ceramic–polymer composite material was used, but different dyes were added to it. A gravimetric analysis revealed similar behavior of the four materials upon controlled heating. Through the mathematical processing of the experimental results obtained by compression tests, empirical mathematical models of the power-type function type were determined. These models highlight the influence exerted by different factors on the force at which the initiation of cracks in the ball materials occurs. The decisive influence of the infill factor on the size of the force at which the cracking of the balls begins was found. [ABSTRACT FROM AUTHOR]

We developed a flexible micro-positioning platform for ceramic material testing to maximize the use of the high amplification ratio of the bridge-type mechanism. This platform uses the bridge-type amplifier mechanism and the laminated piezoelectric ceramic driver as the driving device. It has the capability for three-degree-of-freedom fretting, featuring robust bearing capacity, minimal motion loss during operation, and high transmission efficiency. The magnification and natural frequency expressions of the positioning platform were derived by applying the principles of material mechanics, elastic beam theory, and the Lagrange equation. The magnification and natural frequency of the micro-positioning platform were simulated using finite element software, and the results were analyzed and compared with the theoretical results. The simulation results show the feasibility and high positioning accuracy of the micro-positioning platform. The proposed platform shows application potential in ceramic material testing. [ABSTRACT FROM AUTHOR]

Clays and clay minerals are common natural materials, the unique properties of which have attracted the interest of the industry, especially because these materials are easily available, cheap, and non-toxic. Clays and clay minerals are widely used in many applications, such as in ceramic production, in the clarification of liquids, pollutant adsorbers, filler in composites and nanocomposites, soil amendments, in pharmacy, etc. This review assesses the development in the area of clay application in nanocomposites and ceramics. The first part of this study covers polymer/clay nanocomposites. Topics of interest include nanofiller sources for polymer nanocomposites, the possible ways of clay modification, polymer/clay nanocomposite classification and their processing, and polymer matrix overview with possible enhancement of nanocomposite properties. Some of the applications have already been commercialized. Approximately 80% of the polymer/clay nanocomposites are destined for the automotive, aeronautical, and packaging industries. The second part of this study describes ceramic materials with a focus on silicate ceramics. Talc and kaolinite represent the main natural raw materials for traditional ceramic applications. Less traditional cordierite, steatite, and forsterite could offer property enhancement and seem to be useful in electronics, electrical engineering, catalysts, solar thermal storage, or medical applications. [ABSTRACT FROM AUTHOR]