ABSTRACT A single hot thermocouple technique was employed to examine the dissolution behavior of magnesia (MgO) in CaO‐Al 2 O 3 ‐SiO 2 ternary slags. The Al 2 O 3 content in the slag was varied from 10 to 30 mass%. Cubic MgO single crystals were placed in molten slags at 1550°C, and their apparent volume change ratio was measured to estimate the dissolution rate. The volume was measured by examining the transformation of MgO from a cube to a truncated cube, and finally to a sphere over time. The results indicated that a lower Al 2 O 3 content in the slag led to faster MgO dissolution. MgO was not completely dissolved in the slag containing 30 mass% Al 2 O 3 . However, spinel reaction products were formed at the MgO interface when the Al 2 O 3 content exceeded 20 mass%; therefore, the phenomenon of dissolution in the slag containing 20 mass% Al 2 O 3 was analyzed. MgAl 2 O 4 spinel formed owing to the continuous Al 2 O 3 supply from the bulk slag, and MgO solubility increased as Al 2 O 3 was depleted at the interface. Consequently, MgO dissolution and MgAl 2 O 4 formation occurred simultaneously. The dissolution mechanisms of slags with less than 20% Al 2 O 3 were elucidated using the shrinking core model. The dissolution rates of both slags were controlled by surface reactions.
ABSTRACT Rapid synthesis of the layered compound, lithium chromium (III) oxide (LiCrO 2 )—belonging to the alpha‐sodium iron (III) oxide (α‐NaFeO 2 ) structural family ( R m space group)—via the reactive flash (RF) method, is reported for the first time, achieving complete phase formation at a furnace temperature of ∼260°C within just 2.5 min. A secondary Li‐excess phase, identified as lithium chromium (VI) oxide (Li 2 CrO 4 ), is observed alongside the primary layered phase which is readily removed through aqueous washing followed by drying. Based on observational evidence and region‐specific microstructural and spectroscopic analyses, both chemical reactions (owing to the temperature surge) and probable electrochemical reactions (from the electric field close to the electrodes) of the RF process are identified. While the major phase along the gauge length lies in the proximity of the LiCrO 2 terminal phase, close to the electrodes, it is on the LiCrO 2 –Li 2 CrO 4 binary or LiCrO 2 –Li 2 CrO 4 –Cr 2 O 3 ternary phase fields. Defect equilibria, evaluated using the Brouwer approximation, suggest that Li‐vacancies and accompanying electronic (hole) carriers may dominate electrical conductivity via grains between 30°C–400°C under ambient oxygen partial pressures, with an activation energy of ∼0.14 eV. At elevated temperatures, Li‐ion migration through vacancies becomes increasingly likely. The activation energy for grain boundary conduction is nearly twice that of grain (bulk) conduction, indicating significant microstructural influence on overall transport behavior.
ABSTRACT Bismuth oxyhalides (BiOX) represent a class of layered semiconductor materials with unique [X–Bi–O–Bi–X] structures, offering promising tunability in optoelectronic properties via heterostructure construction. In this study, layered BiOCl/BiOBr van der Waals (vdW) heterostructures with tunable Cl/Br ratios were fabricated via a facile, energy‐efficient room‐temperature hydrolysis strategy. Systematic microstructural characterizations reveal the formation of well‐defined 2D nanosheet assemblies with intimate interfacial contact. Density functional theory (DFT) calculations reveal a work function difference between BiOCl (5.81 eV) and BiOBr (5.73 eV), which spontaneously drives interfacial electron redistribution, establishing a built‐in interfacial electric field (IEF). This IEF, corroborated by charge density difference analysis, facilitates the directional cross‐interface migration of photogenerated carriers, effectively enriching strongly reductive electrons in the conduction band (CB) of BiOBr and strongly oxidative holes in the valence band (VB) of BiOCl. Radical trapping experiments verify that the preserved holes (h + ) act as the dominant active species, synergistically complemented by the photosensitization effect of RhB. Furthermore, the introduction of H 2 O 2 as an electron scavenger further suppresses carrier recombination, maximizing hole utilization. The catalyst maintains robust structural stability over five cyclic runs. Consequently, the optimized heterostructure demonstrates significantly improved photocatalytic activity and robust structural stability. This work provides valuable insights into the interface engineering and charge‐transfer dynamics of bismuth oxyhalide semiconductor ceramics for optoelectronic applications.
ABSTRACT Geopolymers are promising low‐carbon binders for incorporating industrial solid wastes. Waste ceramics, rich in aluminosilicate phases, can serve as potential precursors or aggregates in geopolymer systems. Although previous studies and reviews have summarized their utilization, a mechanism‐based synthesis linking ceramic characteristics, reaction behavior, microstructural evolution, and macroscopic performance remains insufficient. This review critically examines the physicochemical properties, alkali‐activation mechanisms, and structure–property relationships of waste ceramics‐based geopolymers, with emphasis on workability, pore structure, mechanical performance, high‐temperature resistance, shrinkage, and durability. Waste ceramics exhibit a dual role governed by the balance between reactive aluminosilicate dissolution and inert crystalline/filler effects. Their low‐Ca and high‐Si/Al nature, together with stable crystalline phases, can improve thermal stability, reduce shrinkage, and enhance resistance to some aggressive environments. However, excessive ceramic powder replacement may reduce reactivity, increase unreacted particles and porosity, and impair strength development, freeze–thaw resistance, and abrasion resistance. The review highlights a threshold effect of ceramic content and identifies synergistic blending with slag or fly ash as an effective strategy to balance reactivity, pore refinement, and long‐term performance. This work provides a mechanism‐oriented framework for the high‐value utilization and mix design of waste ceramics‐based geopolymers.
ABSTRACT Thermal barrier coatings (TBCs) are widely employed as high‐temperature protective materials for the hot‐section components of aero‐engines. Their performance directly dictates the reliability and operational efficiency of the engine. However, achieving low thermal conductivity while simultaneously retaining a high coefficient of thermal expansion (CTE) and excellent mechanical properties remains a critical challenge in TBC material design. In this study, a non‐stoichiometric high‐entropy strategy was leveraged to synthesize a series of (La 0.2 Nd 0.2 Sm 0.2 Gd 0.2 Yb 0.2 ) 2‐x Zr 2+x O 7 ceramics via a solid‐state reaction method. The effects of excess B‐site Zr 4+ on the microstructure, thermophysical properties, and mechanical performance were systematically investigated. The results indicate that all ceramics exhibit a dual‐phase structure, consisting of pyrochlore and defective fluorite phases. With increasing Zr 4+ content, the pyrochlore phase gradually transforms into the defective fluorite phase. At 1000°C, the thermal conductivity of the materials first decreases and then increases as the fraction of the defective fluorite phase rises, reaching a minimum value of 1.20 W/(m·K). This variation is primarily attributed to the competing mechanisms between changes in the area of the two‐phase interface and the defect concentration. The Vickers hardness ranges from 12.53 to 13.66 GPa, aligning with the trend of relative density. Compared with traditional high‐entropy rare‐earth zirconates, this study integrates non‐stoichiometric regulation with high‐entropy design, allowing the phase fraction and defect population to be adjusted while maintaining favorable CTE and hardness. This work provides a viable strategy for developing next‐generation high‐temperature TBC materials.
ABSTRACT Accelerated carbonation of carbonatable clinkers into building products represents an effective strategy for CO 2 utilization. To expand the compositional design space and application scenarios of such clinkers, this study systematically investigates clinkers with various mineral phase compositions. The phase evolution of limestone and sandstone mixtures under different sintering temperatures, holding times, and Ca/Si ratios was examined. The firing behavior and morphology of the resulting clinkers were also characterized. The results show that clinker composition significantly influences both mechanical properties and CO 2 sequestration performance. Specifically, C 3 S 2 contributes to enhanced compressive strength, while γ‐C 2 S promotes superior CO 2 uptake capacity. Based on these findings, this study systematically summarizes the temperature–time regimes and performance characteristics of four representative low‐calcium clinkers, aiming to provide improved guidance for the design of low‐calcium clinker systems.
ABSTRACT Increasing the breakdown field strength as a valid way for energy storage improvement is always in the spotlight. However, in contrast to improvement in recoverable energy density ( W rec ) by pursuing high electric fields, the achievement in high energy storage coefficient ( W rec / E b ) and efficiency ( η ) at a decent electric field is more pivotal for practical applications. Herein, we induce the phase and domain structure evolution through precise compositional modification aimed at minimizing interfacial polarization. For the (0.67 − x )BiFeO 3 –0.33BaTiO 3 – x K 0.5 Na 0.5 (Nb 0.85 Ta 0.15 )O 3 ceramics, the microstructural and local defect characteristics also ameliorated, enabling a moderate electric field with pronounced polarization. The ability of polarization fully exerted, providing an exceptional W rec of 7.4 J/cm 3 and a remarkable η of 90% in the optimal composition at 418 kV/cm. Moreover, a superior W rec / E b of 0.0176 µC/cm 2 along with extraordinary charge‐discharge performances, including high discharge density ( W d ∼ 5.0 J/cm 3 ), short discharge time ( t 0.9 ∼ 50 ns) were obtained. This work provides beneficial insights for adjusting the energy storage performances of lead‐free relaxor ferroelectric ceramics.
ABSTRACT The in situ formation of carbon fillers has been demonstrated as an effective strategy to eliminate the agglomeration of carbon fillers in ceramic composites. In this study, combustion synthesis was employed to in situ incorporate carbon into a ZrO 2 –SiO 2 ceramic powder using CO 2 gas as the carbon source and magnesium powder as the exothermic medium. The resulting disordered carbon is uniformly distributed within the powder matrix. Furthermore, magnesium element is simultaneously incorporated into the powder as a byproduct. The co‐presence of carbon and magnesium elements synergistically enhances the solid‐state reaction between ZrO 2 and SiO 2 during sintering, facilitating the formation of ZrSiO 4 at a significantly reduced temperature of 1080°C. Meanwhile, the solid‐state reaction significantly promotes the densification of the ceramic composite. The incorporated carbon exhibits strong bonding with the ceramic matrix and remains stable within the matrix up to at least 1000°C. Compared with conventional ZrSiO 4 , the ZrSiO 4 phase formed in this study exhibits much lower decomposition temperature in range of 1000°C–1200°C. Molten copper exhibits pronounced corrosion toward the ceramic composite, primarily through reactions with the SiO 2 phase released from the decomposition of ZrSiO 4 .
ABSTRACT To avoid grain coarsening typical of conventional high‐temperature sintering, this study proposes a low‐temperature reactive sintering strategy for fabricating dense TiC–SiC composites using Ti 3 SiC 2 and graphite powders. The in situ decomposition of Ti 3 SiC 2 accelerates densification via transient liquid Si and highly active TiC x with abundant carbon vacancies. At the optimal temperature of 1600°C, the composite derived from the as‐received precursor (particle size of 4.17 µm) achieved a relative density of 96.08%, a flexural strength of 558 MPa, a hardness of 20.14 GPa, and a fracture toughness of 6.62 MPa·m 1/2 . To further enhance performance without elevating the temperature, the Ti 3 SiC 2 precursor was refined to 2.09 µm. This refinement effectively suppressed grain growth, increasing the relative density to 97.46% at 1600°C and significantly improving the mechanical properties to a flexural strength of 701 MPa, a hardness of 22.06 GPa, and a fracture toughness of 6.88 MPa·m 1/2 . This work demonstrates an effective pathway for the low‐temperature fabrication of high‐performance composite ceramics.
ABSTRACT Graphene oxide (GO) is widely used to enhance ceramic thermoelectrics, but conventional sintering yields incomplete reduction and interfacial defects. Here, we use oxygen‐deficient entropy‐engineered ceramics (EEC) as the matrix for EEC/GO composites. Pre‐existing oxygen‐vacancy‐related defects promote interfacial oxygen transfer and GO deoxygenation during spark plasma sintering (SPS), without requiring a subsequent reducing‐atmosphere annealing treatment. Optimized interfaces lower potential barriers and suppress electron localization, improving conductivity. Meanwhile, rGO induces strong lattice anharmonicity and abundant boundaries, intensifying phonon scattering and reducing thermal conductivity more rapidly with temperature than pure ceramics. We clarify the interfacial reaction and transport mechanisms. Notably, without any post‑annealing treatment, this strategy achieves a ZT of 0.25 at 1073 K, which exceeds previously reported values for SPS‑processed entropy‑engineered SrTiO 3 ‑based ceramics without post‑annealing treatment—while substantially reducing processing time and energy consumption. The defect‐interface synergy overcomes the drawbacks of traditional reduction strategies, offering a new route for precise interface regulation and high‐performance thermoelectric design.
ABSTRACT Cuprous oxide (Cu 2 O) is a typical p‐type oxide semiconductor with a bandgap of approximately 2.0 eV and suitable band position, making it a promising photocathode for photoelectrochemical (PEC) water splitting. However, it faces critical challenges such as low charge separation efficiency and poor photocorrosion stability. Herein, a sandwich‐structured Cu/Cu 2 O/TiO 2 composite photocathode was constructed on FTO conductive glass by combining magnetron sputtering with electrodeposition. In this architecture, the metallic Cu interlayer serves a triple role: enhancing the substrate conductivity, providing nucleation sites to induce the preferential growth of Cu 2 O along the highly active (111) crystal plane, and simultaneously generating hot electrons via the surface plasmon resonance (SPR) effect to protect carrier generation. The dense TiO 2 overlayer suppresses photocorrosion and forms a p–n heterojunction with Cu 2 O, facilitates efficient spatial charge separation. The resulting Cu/Cu 2 O/TiO 2 photoelectrode achieves a photocurrent density of ‐7.2 mA·cm −2 at 0 V vs. RHE, which is 1.57 and 1.33 times higher than those of pure Cu 2 O and Cu/Cu 2 O, respectively. Through band gradient modulation, this approach reduces charge transfer resistance and prolongs carrier lifetime, confirming the synergistic effects of the Cu SPR layer and the TiO 2 heterojunction. This work presents a versatile strategy for designing high‐performance and durable Cu 2 O‐based photocathodes by combining plasmonic enhancement with heterojunction engineering.
ABSTRACT Alumina–iron composites are attractive for structural and functional applications but are difficult to consolidate because molten Fe poorly wets Al 2 O 3 , promoting capillary‐driven segregation during conventional liquid‐phase sintering. Here, we show that ultrafast nonequilibrium CO 2 laser sintering enables rapid consolidation of this unstable system while limiting liquid‐phase redistribution. Al 2 O 3 –Fe slurries containing 20–50 vol% Fe were tape‐cast and processed under argon using single‐pass laser scanning. The results indicate that Al 2 O 3 remains predominantly solid and densifies by diffusion, while Fe transiently melts and undergoes limited viscous flow. Rapid heating and cooling restrict droplet coalescence, producing a consolidated Al 2 O 3 matrix with a fine, dispersed metallic phase. Increasing scan speed refines the Fe features, consistent with a shorter time available for liquid‐phase redistribution. Quantitative two‐dimensional analysis of the BSE micrographs further supports the scan‐speed‐dependent refinement of the Fe‐rich phase. SEM, TEM, XRD, and STEM‐EDS reveal discrete Al 2 O 3 –Fe interfaces without a continuous reaction layer, while localized FeAl 2 O 4 spinel forms at Al 2 O 3 grain boundaries. This work supports ultrafast laser sintering as a route for consolidating nonwetting ceramic–metal systems.
ABSTRACT The present study investigates curing‐temperature effects on hydration and microstructural evolution of metakaolin‐rich calcined kaolinitic clay (MK), quartz powder (Q), and gypsum induced belite binders. A β‐Dicalcium silicate (β‐C 2 S)‐rich powder was synthesized using Boric acid (H 3 BO 3 ) as a polymorph stabilizer, followed by blending with either MK or Q‐rich reference filler, together with 5 wt% gypsum, and cured at 27°C, 40°C and 55°C at a water‐to‐binder ratio of 0.40. Hydration kinetics, phase assemblage, hydrate structure, and pore structure were characterized using isothermal calorimetry, quantitative X‐ray diffraction (QXRD), thermogravimetric analysis/differential thermogravimetry (TGA–DTG), 29 Si and 27 Al magic‐angle spinning nuclear magnetic resonance (MAS NMR), scanning electron microscopy with backscattered electron imaging and energy‐dispersive X‐ray spectroscopy (SEM/BSE–EDX) and mercury intrusion porosimetry (MIP). It was inferred that elevated curing temperature strongly accelerated early heat evolution. XRD‐Rietveld revealed that at 28 day—degree of hydration (DoH) was only 31.4% at 55°C, whereas the quartz blend's hydration increased up to 82.3% at 55°C. NMR study showed that higher curing temperature and MK addition yielded a more polymerized Calcium‐Alumino‐Silicate‐Hydrate (C–(A)–S–H) gel (higher mean chain length (MCL)). SEM–EDX showed that for MK induced mixes, the microstructure evolved as a denser but more heterogeneous assemblage at 55°C. Overall, these findings show that curing‐temperature effects depend strongly on blend chemistry and require performance‐based validation.
ABSTRACT Ruthenium‐doped yttrium aluminum garnet (YAG:Ru) ceramics were synthesized by chemical precipitation. The effects of sintering conditions and the amount and type of sintering additives on the optical properties of YAG:Ru ceramics were investigated. A comparative analysis of the optical properties and color centers was performed as a function of the concentrations of Mg 2+ , Ca 2+ , and Si 4+ cations. It was found that the maximum linear light transmittance (72% at 1100 nm) was achieved with the addition of MgO or CaO at sintering temperatures of 1800°C and 1825°C, respectively, whereas the use of SiO 2 resulted in a lower transmittance of 58% at 1850°C. The color of the samples varied from red (without additives, with SiO 2 , and with high concentrations of CaO) to gray (with MgO and CaO 0.05 wt%), which could be associated with the formation of different color centers. Several absorption bands in the visible and near‐IR range were found for the YAG:Ru ceramic samples: approximately 2130 nm (0.58 eV, for the sample containing CaO), approximately 1348 nm (0.92 eV, without additives and with SiO 2 ), approximately 585 nm (2.11 eV, without additives), and bands at approximately 450–465 nm and approximately 340 nm (2.75–2.67 and 3.65 eV, respectively, for all samples). Two narrow bands at 648 and 672 nm were detected in the photoluminescence spectra under excitation at 310 nm. These bands appeared in samples with CaO, MgO, and even in undoped YAG, but disappeared upon the introduction of SiO 2 . These results open the possibility of controlling the optical properties of YAG:Ru ceramics by varying the type of sintering additive, revealing potential applications in laser and photochromic systems.
ABSTRACT Polymer‐derived ceramics (PDCs) have emerged as a versatile class of materials. Their unique processing route—from molecularly designed preceramic polymers to tailored ceramic architectures—enables precise control over composition, microstructure, and functionality. This review provides a comprehensive overview of recent advances in PDCs research, with emphasis on both fundamental aspects and practical applications. After introducing the chemical basis of preceramic polymers and their transformation into ceramics, we highlight strategies to tailor ceramic properties through elemental doping, nanostructuring, and composite design, including the development of high‐entropy systems. Particular attention is devoted to energy‐related applications, where PDCs serve as electrodes, electrolytes, catalysts, and functional supports in batteries, fuel cells, supercapacitors, thermoelectrics, and photocatalysis. Their role in environmental technologies is equally examined, spanning porous membranes for water purification, adsorbents for pollutant removal, gas separation, sensing, and advanced thermal insulation. The review also discusses recent progress in shaping technologies, such as additive manufacturing and fiber processing, which expand the design space for complex architectures. By integrating molecular‐level chemistry with multiscale processing and application‐driven design, PDCs are positioned as a key materials platform for sustainable energy conversion and environmental remediation. Finally, we outline current challenges and future opportunities aimed at enhancing their performance, scalability, and integration into next‐generation technologies.
ABSTRACT Single‐phase multiferroic BiFeO 3 exhibits antiferromagnetism and weak magnetoelectric (ME) coupling due to its cycloidal spin structure (period ≈ 62 nm), which fundamentally limits its ME–piezo–photocatalytic activity. Herein, we demonstrate that Sm doping in (Bi 1−x Sm x )FeO 3 ( x = 0–0.2) induces lattice‒distortion coupling that disrupts the spin cycloid and releases latent magnetization, leading to Sm‐doping‐dependent modulation of multiferroicity, ME coupling, and optical properties, with optimal piezo–photocatalysis ( x = 0.15). This lattice‒distortion coupling is further nanoconfined within the one‐dimensional boundaries of the nanoporous hollow (Bi 0.85 Sm 0.15 )FeO 3 ceramic nanofibers (NFs) fabricated by sol‒gel‒electrospinning. The resulting fibers provide abundant catalytic sites, enhanced ferro/piezoelectricity, and a narrowed band gap (2.02 eV), achieving an ME–piezo–photocatalytic rate constant of 2.7 × 10 −2 min −1 . Cyclic tests yield rate constants of 1.77 ± 0.17, 0.84 ± 0.48, and 2.97 ± 0.59 × 10 −2 min −1 , after excluding the outlier, the mean value is 2.50 × 10 −2 min −1 (RSD = 24.8%). Combined with the morphological and microstructural observations, these results confirm the good stability and reusability. The synergistic enhancement originates from ferroelectric and ME vibration‐induced built‐in electric fields that effectively suppress photogenerated electron–hole recombination. This study demonstrates that lattice‒distortion coupling in rare‐earth‐doped BiFeO 3 NFs provides a promising strategy for enhancing ME–piezo–phototronics in environmental remediation.
ABSTRACT The molecular behaviors of C–S–H is of significance to the micro‐/macro‐performances of sustainable cement‐based materials, while their quantitative correlation spanning from molecular to macro is still much elusive. Given that C–S–H gel commonly encounters self‐reaction growth and external metal cations attack (Na + , K + , Ca 2+ , Mg 2+ , and Al 3+ ), this study takes it as a model to investigates its multiscale response mechanisms in terms of molecular structure, microstructure, and micro‐/macro‐mechanical properties, analyzing weightings between multiscale factors. Results show that the crystallinity degree increases with self‐reaction growth age, accompanied by water removal, conversion to OH − , and OH − dissociation. Monovalent metal cations enhance C–S–H gel compactness mainly via surface adsorption and its induced agglomeration, whereas multivalent metal cations exhibit both physical and chemical effects, manifested as ion intercalation affecting the molecular interlayer spacing. Notably, the weight of the interlayer spacing of C–S–H, a key molecular‐level feature, on the splitting tensile strength is far greater than that of the mean chain length of C‐S‐H, and even exceeds those of porosity and bulk density. This confirms the importance of molecular interlayer bonding within C–S–H gel for its macroscopic tensile properties.
ABSTRACT Although NaAlH 4 is considered a promising hydrogen storage material due to its high hydrogen storage capacity (7.5 wt%), its practical application is limited by the high dehydrogenation temperature, slow reaction dynamics and limited reversibility. To solve these problems, we investigate the influence of Li‐doping on the hydrogen storage capacity, hydrogen desorption energy, electronic and optical properties of NaAlH 4 . The results show that the theoretical hydrogen storage capacity of NaAlH 4 increases with increasing Li‐doped concentration, reaching a maximum of 9.6 wt%. Compared with undoped NaAlH 4 , the hydrogen storage capacity of Li‐doped NaAlH 4 is enhanced by 28%. However, an increase in Li‐doped concentration may lead to the formation of LiH phase, which could reduce its reversible hydrogen storage capacity. Although Li‐doped NaAlH 4 remains thermodynamically stable, its thermal stability decreases with increasing Li‐doping concentration. Compared to parent NaAlH 4 , it is beneficial to hydrogen release. Ab‐initio molecular dynamics (AIMD) simulation further confirmed the thermodynamic stability of Li‐doped NaAlH 4 . Furthermore, the calculated hydrogen desorption energy indicates that Li‐doped reduces the activation energy barrier for hydrogen release, which promotes hydrogen dissociation and desorption. This behavior is related to Li‐induced local charge redistribution, which weakens the bond strength between the Al–H bond in the [AlH 4 ] group. The reduction in Al–H bond energy reduces the reaction energy barrier during the dehydrogenation process, which accelerates the hydrogen release from the NaAlH 4 . This mechanism is further confirmed by band structure, which shows that the band gap gradually narrows with the Li‐doped concentration increases. The narrowing of the band gap enhances electronic transition near the electron free energy surface, which promotes hydrogen release.
ABSTRACT Additive manufacturing of ultrahigh‐temperature ceramics, such as ZrB 2 –SiC composites, remains challenging owing to limited understanding of laser‐induced melting and solidification behavior across a wide composition range. We investigated the melting and solidification behavior of ZrB 2 –SiC powder compacts during laser irradiation using microstructural analysis and in situ synchrotron radiation x‐ray imaging. Laser irradiation formed melted and sintered regions. A partially melted region containing both melted and sintered microstructures was observed between these regions. The eutectic composition of the laser‐melted ZrB 2 –SiC composites was estimated to lie between ZrB 2 –57.5 mol% SiC and ZrB 2 –60 mol% SiC. Compositions far from eutectic, such as ZrB 2 –50 mol% SiC and ZrB 2 –70 mol% SiC, exhibited cracks and voids, whereas such defects were rarely observed in near‐eutectic composition melted regions. In situ transmission imaging revealed melting, solidification, and void formation during laser irradiation and subsequent cooling, consistent with post‐process microstructure observations. ZrB 2 in eutectic microstructure exhibited a blocky morphology with its primary growth direction <0001> approximately parallel to the solidification direction, whereas SiC formed a rod‐like morphology with the <110> primary growth direction approximately parallel to the solidification direction. Thus, near‐eutectic compositions in the ZrB 2 –SiC system enable effective densification and microstructural control through laser‐induced melting and solidification.
ABSTRACT Glass‐ceramics produced through controlled crystallization exhibit properties that are strongly governed by their microstructures. However, quantitative characterization of microstructural evolution is often labor‐intensive and subject to operator‐dependent variability. In this study, a generative adversarial network (GAN)‐based framework was developed to predict the microstructures of sodium borosilicate glass‐ceramics prepared from commercial Pyrex 7740 under different heat‐treatment conditions. The proposed model, designated as a kinetically guided regression‐based conditional Wasserstein GAN with gradient penalty (KG‐RC‐WGAN‐GP), integrates a kinetics‐guided surrogate model with auxiliary regression branches to ensure that the generated microstructures are consistent with both experimental crystallization kinetics and prescribed processing parameters. The model was validated using experimental scanning electron microscopy images and successfully reproduced the crystallization trends and the temperature‐dependent variation in Avrami exponents. Morphological analysis further confirmed that the generated images agreed well with the experimental results in terms of crystal size, aspect ratio, circularity, and spatial distribution. This framework provides an efficient approach for establishing process−microstructure relationships and accelerating the data‐driven design of glass‐ceramic materials.
