Ultrahigh toughness zirconia ceramics.

The attainment of both high strength and toughness is the ultimate goal for most structural materials. Although ceramic material has been considered for use as a structural material due to its high strength and good chemical stability, it suffers from the limitation of low toughness. For instance, although Y2O3-stabilized tetragonal ZrO2 polycrystals (Y-TZPs) exhibit remarkable toughness among ceramics due to their phase transformation toughening mechanism, this toughness is still much weaker than that of metals. Here, we report Y-TZP-based ceramic materials with toughnesses exceeding 20 MPa m1/2, which is comparable to those of metals, while maintaining strengths over 1,200 MPa. The superior mechanical properties are realized by reducing the phase stability of tetragonal zirconia by tailoring the microstructure and chemistry of the Y-TZP. The proposed ceramic materials can further advance the design and application of ceramic-based structural materials.

Archaeological evidence for initial migration of Neolithic Proto Sino-Tibetan speakers from Yellow River valley to Tibetan Plateau.

Sino-Tibetan is the second largest language family in the world. Recent linguistic and genetic studies have traced its origin to Neolithic millet farmers in the Yellow River region of China around 8,000 y ago and also suggested that initial divergence among branches of Sino-Tibetan coincided with expansion of the Neolithic Yangshao culture to the west and southwest during the sixth millennium BP. However, archaeological investigations to date have been insufficient to understand the lifeways of these migrant Proto Sino-Tibetan speakers. Here, we present the results of the interdisciplinary research on the material culture and ritual activities related to the initial southwestward migration of Yangshao populations, based on evidence from microfossil remains on ceramics at three sites in Gansu and Sichuan, regional archaeological contexts, and ethnographic accounts of modern Gyalrong Tibetans. The first Yangshao migrants may have integrated with indigenous hunter-gatherers in the NW Sichuan highlands, and adopted broad-spectrum subsistence strategies, consisting of both millet farming and foraging for local wild resources. Meanwhile, the migrants appear to have retained important ritual traditions previously established in their Yellow River homelands. They prepared qu starter with Monascus mold and rice for brewing alcoholic beverages, which may have been consumed in communal drinking festivals associated with the performance of ritual dancing. Such ritual activities, which to some extent have survived in the skorbro-zajiu ceremonies in SW China, may have then played a central role in maintaining and reinforcing cultural identities, social values, and connections with the homelands of the Proto Sino-Tibetan migrants.

Dating the emergence of dairying by the first farmers of Central Europe using 14C analysis of fatty acids preserved in pottery vessels.

Direct, accurate, and precise dating of archaeological pottery vessels is now achievable using a recently developed approach based on the radiocarbon dating of purified molecular components of food residues preserved in the walls of pottery vessels. The method targets fatty acids from animal fat residues, making it uniquely suited for directly dating the inception of new food commodities in prehistoric populations. Here, we report a large-scale application of the method by directly dating the introduction of dairying into Central Europe by the Linearbandkeramik (LBK) cultural group based on dairy fat residues. The radiocarbon dates (n = 27) from the 54th century BC from the western and eastern expansion of the LBK suggest dairy exploitation arrived with the first settlers in the respective regions and were not gradually adopted later. This is particularly significant, as contemporaneous LBK sites showed an uneven distribution of dairy exploitation. Significantly, our findings demonstrate the power of directly dating the introduction of new food commodities, hence removing taphonomic uncertainties when assessing this indirectly based on associated cultural materials or other remains.

Gradient Functional Layer Anode for Carbonate-Superstructured Solid Fuel Cells with Ethane Fuel.

Carbonate-superstructured solid fuel cells (CSSFCs) are an emerging type of fuel cells with high flexibility of fuels. However, using ethane fuel for solid fuel cells is a great challenge due to serious degradation of their anodes. Herein, this critical issue is solved by creating a novel gradient functional layer anode for CSSFCs. First, a finer-scale anode with a larger surface area is demonstrated to provide more active sites for the internal reforming reaction of ethane, achieving a 60% higher ethane conversion rate and 40% lower polarization resistance than conventional anodes. Second, incorporating a gradient functional layer into the anode results in an additional 50% enhancement in the peak power density of CSSFCs to a record high value (up to 241 mW cm-2) with dry ethane fuel at a low temperature of 550 °C, which is even comparable to the power density of conventional solid oxide fuel cells above 700 °C. Furthermore, the CSSFC with the gradient anode exhibits excellent durability for over 200 h. This finding provides a new strategy to develop efficient anodes for hydrocarbon fuels.

Volumetric Additive Manufacturing of SiOC by Xolography.

Additive manufacturing (AM) of ceramics has significantly contributed to advancements in ceramic fabrication, solving some of the difficulties of conventional ceramic processing and providing additional possibilities for the structure and function of components. However, defects induced by the layer-by-layer approach on which traditional AM techniques are based still constitute a challenge to address. This study presents the volumetric AM of a SiOC ceramic from a preceramic polymer using xolography, a linear volumetric AM process that allows to avoid the staircase effect typical of other vat photopolymerization techniques. Besides optimizing the trade-off between preceramic polymer content and transmittance, a pore generator is introduced to create transient channels for gas release before decomposition of the organic constituents and moieties, resulting in crack-free solid ceramic structures even at low ceramic yield. Formulation optimization alleviated sinking of printed parts during printing and prevented shape distortion. Complex solid and porous ceramic structures with a smooth surface and sharp features are fabricated under the optimized parameters. This work provides a new method for the AM of ceramics at µm/mm scale with high surface quality and large geometry variety in an efficient way, opening the possibility for applications in fields such as micromechanical systems and microelectronic components.

Enhanced Temperature Stability of Pyroelectric Sensing in Multilayer Potassium Sodium Niobate-Based Ceramics with Graded Polarization Rotation.

Pyroelectric effect which refers to electrical responses induced by time temperature-dependent fluctuations has received extensive attention, showing promising application prospects for infrared (IR) technology. Although enhanced pyroelectric performances are obtained in potassium sodium niobate-based ceramics at room temperature via multi-symmetries coexistence design, the poor pyroelectric temperature stability is still an urging desire that needs to be resolved. Herin, by constructing multilayer composite ceramics and adjusting the proportion of stacked layers, improved pyroelectric coefficient, and figures of merit (FOMs), as well as enhanced temperature stabilities can be achieved. With a remained high pyroelectric coefficient of 5.45 × 10-4 C m-2°C-1 at room temperature, the pyroelectric parameters almost keep unchanged in the temperature range of 30-100 °C, showing great properties advantages compared with previous reports. The excellent properties can be attributed to the graded polarization rotation states among each lamination induced by successive phase transitions. The novel strategy for achieving stable pyroelectric sensing can further promote the application in the IR sensors field.

Ultrahigh Energy Storage Density and Efficiency of Lead-Free Dielectrics with Sandwich Structure.

Lead-free dielectric capacitors have attracted significant research interest for high-power applications due to their environmental benefits and ability to meet the demanding performance requirements of electronic devices. However, the development of lead-free ceramic dielectrics with outstanding energy storage performance remains a challenge. In this study, environmentally friendly ceramic dielectrics with sandwich structures are designed and fabricated to improve energy storage performance via the synergistic effect of different dielectrics. The chemical compositions of the outer and middle layers of the sandwich structure are 0.35BiFeO3 -0.65SrTiO3 and Bi0.39 Na0.36 Sr0.25 TiO3 , respectively. The experimental and theoretical simulation results demonstrate that the breakdown strength is over 700 kV cm-1 for prepare sandwich structure ceramics. As a result, an ultrahigh recoverable energy storage density of 9.05 J cm-3 and a near-ideal energy storage efficiency of 97% are simultaneously achieved under 710 kV cm-1 . Furthermore, the energy storage efficiency maintains high values (≥ 96%) within 1-100 Hz and the power density as high as 188 MW cm-3 under 400 kV cm-1 . These results indicate that the designed lead-free ceramics with a sandwich structure possess superior comprehensive energy storage performance, making them promising lead-free candidates in the energy storage field.

High Energy Storage Performance in BiFeO3-Based Lead-Free High-Entropy Ferroelectrics.

Dielectric capacitors are widely used in advanced electrical and electronic systems due to the rapid charge/discharge rates and high power density. High comprehensive energy storage properties are the ultimate ambition in the field of application achievements. Here, the high-entropy strategy is proposed to design and fabricate single-phase homogeneous (Bi0.5Ba0.1Sr0.1Ca0.2Na0.1)(Fe0.5Ti0.3Zr0.1Nb0.1)O3 ceramic, the hierarchical heterostructure including rhombohedral-tetragonal multiphase nanoclusters and locally disordered oxygen octahedral tilt can lead to the increased dielectric relaxation, diffused phase transition, diverse local polarization configurations, grain refinement, ultrasmall polar nanoregions, large random field, delayed polarization saturation and improved breakdown field. Accordingly, a giant Wrec ≈13.3 J cm-3 and a high η ≈78% at 66.4 kV mm-1 can be simultaneously achieved in the lead-free high-entropy BiFeO3-based ceramic, showing an obvious advantage in overall energy-storage properties over BiFeO3-based lead-free ceramics. Moreover, an ultrafast discharge rate (t0.9 = 18 ns) can be achieved at room temperature, concomitant with favorable temperature stability in the range of 20-160 °C, due to the enhanced diffuse phase transition and fast polarization response. This work provides a feasible pathway to design and generate dielectric materials exhibiting high comprehensive energy-storage performance.

Local Isomeric Polar Nanoclusters Enabled Superior Capacitive Energy Storage Under Moderate Fields in NaNbO3-Based Lead-Free Ceramics.

The high-field energy-storage performance of dielectric capacitors has been significantly improved in recent years, yet the high voltage risks of device failure and large cost of insulation technology increase the demand for high-performance dielectric capacitors at finite electric fields. Herein, a unique superparaelectric state filled with polar nanoclusters with various local symmetries for lead-free relaxor ferroelectric capacitors is subtly designed through a simple chemical modification method, successfully realizing a collaborative improvement of polarization hysteresis, maximum polarization, and polarization saturation at moderate electric fields of 20-30 kV mm-1. Therefore, a giant recoverable energy density of ≈5.0 J cm-3 and a high efficiency of ≈82.1% are simultaneously achieved at 30 kV mm-1 in (0.9-x)NaNbO3-0.1BaTiO3-xBiFeO3 lead-free ceramics, showing a breakthrough progress in moderate-field comprehensive energy-storage performances. Moreover, superior charge-discharge performances of high-power density ≈182 MW cm-3, high discharge energy density ≈4.3 J cm-3 and ultra-short discharge time <70 ns as well as excellent temperature stability demonstrate great application potentials for dielectric energy-storage capacitors in pulsed power devices. This work provides an effective and paradigmatic strategy for developing novel lead-free dielectrics with high energy-storage performance under finite electric fields.

Superior Energy Storage Capability and Fluorescence Negative Thermal Expansion of NaNbO3-Based Transparent Ceramics by Synergistic Optimization.

Transparent dielectric ceramics are splendid candidates for transparent pulse capacitors (TPCs) due to splendid cycle stability and large power density. However, the performance and service life of TPCs at present are threatened by overheating damage caused by dielectric loss. Here, a cooperative optimization strategy of microstructure control and superparaelectric regional regulation is proposed to simultaneously achieve excellent energy storage performance and real-time temperature monitoring function in NaNbO3-based ceramics. By introducing aliovalent ions and oxides with large bandgap energy, the size of polar nanoregions is continuously reduced. Due to the combined effect of increased relaxor behavior and fine grains, excellent comprehensive performances are obtained through doping appropriate amounts of Bi, Yb, Tm, and Zr, Ta, Hf in A- and B-sites of the NaNbO3 matrix, including recoverable energy storage density (5.39 J cm-3), extremely high energy storage efficiency (91.97%), ultra-fast discharge time (29 ns), and superior optical transmittance (≈47.5% at 736 nm). Additionally, the phenomenon of abnormal fluorescent negative thermal expansion is realized due to activation mechanism of surface phonon at high temperatures that can promote the formation of [Yb···O]-Tm3+ pairs, showing great potential in real-time temperature monitoring of TPCs. This research provides ideas for developing electronic devices with multiple functionalities.

Pressureless Welding of Temperature-Invariant Multifunctionality Body Based on Hydroxyl-Functionalized Boron Nitride Nanosheets and Bifunctional Monoethanolamine Cross-linker.

Bulk hexagonal boron nitride (h-BN) ceramics with structural integrity, high-temperature resistance and low expansion rate are expected for multifunctional applications in extreme conditions. However, due to its sluggish self-diffusion and intrinsic inertness, it remains a great challenge to overcome high-energy barrier for h-BN powder sintering. Herein, a cross-linking and pressureless-welding strategy is reported to produce bulk boron nitride nanosheets (BNNSs) ceramics with well-crystalized and dense B-N covalent-welding frameworks. The essence of this synthesis strategy lies in the construction of >B─O─H2C─H2C─H2N:→B< bond bridge connection structure among hydroxyl functionalized BNNSs (BNNSs-OH) using bifunctional monoethanolamine (MEA) as cross-linker through esterification and intermolecular-coordination reactions. The prepared BNNSs-interlaced ceramics have densities not less than 1.2 g cm-3, and exhibit exceptional mechanical robustness and resiliency, excellent thermomechanical stability, ultra-low linear thermal expansion coefficient of 0.06 ppm °C-1, and high thermal diffusion coefficient of 4.76 mm2 s-1 at 25 °C and 3.72 mm2 s-1 at 450 °C. This research not only reduces the free energy barrier from h-BN particles to bulk ceramics through facile multi-step physicochemical reaction, but also stimulates further exploration of multifunctional applications for bulk h-BN ceramics over a wide temperature range.

Realizing Outstanding Energy Storage Performance in KBT-Based Lead-Free Ceramics via Suppressing Space Charge Accumulation.

The great potential of K1/2Bi1/2TiO3 (KBT) for dielectric energy storage ceramics is impeded by its low dielectric breakdown strength, thereby limiting its utilization of high polarization. This study develops a novel composition, 0.83KBT-0.095Na1/2Bi1/2ZrO3-0.075 Bi0.85Nd0.15FeO3 (KNBNTF) ceramics, demonstrating outstanding energy storage performance under high electric fields up to 425 kV cm-1: a remarkable recoverable energy density of 7.03 J cm-3, and a high efficiency of 86.0%. The analysis reveals that the superior dielectric breakdown resistance arises from effective mitigation of space charge accumulation at the interface, influenced by differential dielectric and conductance behaviors between grains and grain boundaries. Electric impedance spectra confirm the significant suppression of space charge accumulation in KNBNTF, attributable to the co-introduction of Na1/2Bi1/2ZrO3 and Bi0.85Nd0.15FeO3. Phase-field simulations reveal the emergence of a trans-granular breakdown mode in KNBNTF resulting from the mitigated interfacial polarization, impeding breakdown propagation and increasing dielectric breakdown resistance. Furthermore, KNBNTF exhibits a complex local polarization and enhances the relaxor features, facilitating high field-induced polarization and establishing favorable conditions for exceptional energy storage performance. Therefore, the proposed strategy is a promising design pathway for tailoring dielectric ceramics in energy storage applications.

Characterization and In Vitro Behavior of PEO Coated Mg Modified with Antibacterial Ag(I) and Cu(II) Complexes.

The use of Mg-based biomaterials with a number of their advantageous properties are overshadowed by uncontrollable metal corrosion. Moreover, the use of implants goes alongside with the threat of pathogens-associated complications. In this study, PEO coated Mg biomaterial loaded with antibacterial Ag(I) and Cu(II) complexes is produced and tested to meet both appropriate protective characteristics as well as sufficient level of antibacterial activity. To achieve a suitable level of anticorrosion protection phosphate and fluoride-phosphate electrolytes are used in the PEO process. Investigation of the surface thickness and morphology done by means of cross-section analysis and scanning electron microscopy (SEM), as well as electrochemical impedance spectroscopy (EIS) assay show precedence of the fluoride containing PEO coating and make it the material of choice for further modification with Ag(I) and Cu(II) complexes. The presence of the complexes on the PEO surface is confirmed by energy dispersive X-ray spectroscopy (EDX). X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and glow discharge optical emission spectroscopy (GDOES) are used to estimate the complexes' chemical state and depth of penetration in the coating surface. Based on the results of antibacterial assay, the modified coatings are found to be active against both Gram-positive and Gram-negative bacteria.

Development of Membranes and Separators to Inhibit Cross-Shuttling of Sulfur in Polysulfide-Based Redox Flow Batteries: A Review.

The global rapid transition from fossil fuels to renewable energy resources necessitates the implementation of long-duration energy storage technologies owing to the intermittent nature of renewable energy sources. Therefore, the deployment of grid-scale energy storage systems is inevitable. Sulfur-based batteries can be exploited as excellent energy storage devices owing to their intrinsic safety, low cost of raw materials, low risk of environmental hazards, and highest theoretical capacities (gravimetric: 2600 Wh/kg and volumetric: 2800 Wh/L). However, sulfur-based batteries exhibit certain scientific limitations, such as polysulfide crossover, which causes rapid capacity decay and low Coulombic efficiency, thereby hindering their implementation at a commercial scale. In this review article, we focus on the latest research developments between 2012-2023 to improve the separators/membranes and overcome the shuttle effect associated with them. Various categories of ion exchange membranes (IEMs) used in redox batteries, particularly polysulfide redox flow batteries and lithium-sulfur batteries, are discussed in detail. Furthermore, advances in IEM constituents are summarized to gain insights into different fundamental strategies for attaining targeted characteristics, and a critical analysis is proposed to highlight their efficiency in mitigating sulfur cross-shuttling issues. Finally, future prospects and recommendations are suggested for future research toward the fabrication of more effective membranes with desired properties.

Flower like-novel nanocomposite of Mg(Ti0.99Sn0.01)O3decorated on reduced graphene oxide (rGO) with high capacitive behavior as supercapacitor electrodes.

In this study, ceramic materials of Mg(Ti0.99Sn0.01)O3were synthesized and decorated on reduced graphene oxide, forming a nanocomposite of rGO/Mg(Ti0.99Sn0.01)O3(rGO/MTS001). The successful synthesis results were confirmed by XRD, UV-vis analysis, FT-IR, and SEM-EDS. The MTS001 has a flower-like morphology from scanning electron microscopy (SEM) analysis, and the nanocomposites of rGO/MTS001 showed MTS001 particles decorated on the rGO's surface. The electrochemical performance of rGO/MTS001 and MTS001 was investigated by determining the specific capacitance obtained in 1 M H2SO4solution by cyclic voltammetry, followed by galvanostatic charge-discharge analysis using a three-electrode setup. The rGO/MTS001 achieved a specific capacitance of 361.97 F g‒1, compared to MTS001 (194.90 F g‒1). The capacitance retention of rGO/MTS001 nanocomposite also depicted excellent cyclic stability of 95.72% after 5000 cycles at a current density of 0.1 A g‒1. The result showed that the nanocomposite of ceramics with graphene materials has a potential for high-performance supercapacitor electrodes.

Finishing technique effect on strength of zirconia-reinforced lithium silicate ceramic.

The aim of this study was to evaluate the effect of two finishing techniques, glazing or polishing, in comparison with the as-cut condition, on the biaxial-flexural-strength (BFS) of a zirconia-reinforced lithium silicate ceramic (ZLS). Cylinders were milled from CAD/CAM blocks and sliced to obtain disc-shaped specimens (ISO6872:2015). Polished and glazed specimens were processed following the manufacturer's instructions. Thirty-three specimens were obtained for each condition and microstructural and BFS/fractographic characterizations were performed. BFS and roughness data were analyzed using Weibull statistics and ANOVA one-way with Tukey post-hoc test, respectively. While a rougher surface was observed for as-cut specimens, smoother surfaces were observed for polished and glazed ZLS at microscopical evaluation and confirmed through surface-roughness evaluation. X-ray spectra depicted a glass phase for all groups and characteristic metasilicate, lithium disilicate, and lithium phosphate peaks for the as-cut and polished specimens. Glazed specimens showed higher characteristic strength than polished and as-cut specimens, which did not differ significantly. While higher Weibull-modulus was observed for the polished than for the as-cut specimens, no statistically significant differences were noted between glazed and polished, and between glazed and as-cut specimens. ZLS presents higher strength when glazed, and polishing increases the structural reliability of the material relative to the as-cut condition. Both finishing techniques reduced surface roughness similarly.

Drug eluting bioactive glass ceramics for fusion in spondylodiscitis: a pilot study.

Retrospective observational study. To determine the efficacy and safety of bioactive glass ceramics mixed with autograft in the treatment of spondylodiscitis. Thirty-four patients with spondylodiscitis underwent surgery using autologous bone graft augmented by antibiotic loaded bioactive glass ceramic granules. Twenty-five patients aging 6 to 77, completed 1-year follow-up. The lumbosacral junction was affected in 3, lumbar spine in 13, one each in the dorso-lumbar junction and sacrum, and 7 dorsal spines. The organism isolated was Mycobacterium tuberculosis in 15, Methicillin sensitive Staphylococcus aureus (MSSA) in 4, Pseudomonas aeruginosa in 4, Klebsiella pneumoniae in one, Burkholderia pseudomallei in 1, and mixed infections in 2. All patients had appropriate antibiotic therapy based on culture and sensitivity. Clinical and radiological evaluation of all the patients was done at 6 weeks, 3 months, 6 months, and 12 months after the surgery. Twenty-three patients improved clinically and showed radiographic fusion between 6 and 9 months. The patient with Burkholderia infection died due to fulminant septicemia with multi organ failure while another patient died at 9 months due to an unrelated cardiac event. The mean Visual Analogue Score (VAS) at the end of 1-year was 2 with radiological evidence of fusion in all patients. There were no re-infections or discharging wounds, and the 30-day re-admission rate was 0. Bioactive glass ceramics is a safe and effective graft expander in cases of spondylodiscitis. The absorption of antibiotics into the ceramic appears to help the elimination of infection.

Synthesis and investigation of novel boron- and magnesium-doped YAG:Ce and LuAG:Ce phosphor ceramics.

YAG:Ce and LuAG:Ce ceramics are widely used as scintillator materials that convert high-energy radiation into visible light. For the practical application of such compounds, short decay times are a necessity. One way of shortening the existing decay times even more is to change the local environment of emitting ions by means of doping the matrix with additional elements, for example, boron or magnesium. Furthermore, boron ions also can help absorb gamma rays more efficiently, therefore improving overall applicability. Due to the aforementioned reasons, YAG and LuAG ceramics doped with cerium, boron, and magnesium were synthesized. Initial amorphous powders have been obtained by means of sol-gel synthesis and pressed into pellets under isostatic pressure and finally calcinated to form crystalline ceramics. The effects of boron and magnesium doping on the morphological, structural, and luminescence properties were investigated. The key results showed that doping with boron has indeed shortened the decay times of the garnet pellets. Overall, boron doping of ceramics is a relatively new research area; however, it is rather promising as it helps both to improve the luminescence properties and to increase particle growth rate.

Novel yellowish-green single-phased spinel Mg1-xBaxAl2O4:Mn2+ phosphor(s) for color rendering white-light-emitting diodes.

For white light-rendering research activities, interpretation by using colored emitting materials is an alternative approach. But there are issues in designing the white color emitting materials. Particularly, differences in thermal and decay properties of discrete red, green, and blue emitting materials led to the quest for the search of a single-phased material, able to emit primary colors for white light generation. The current study is an effort to design a simple, single-phase, and cost-effective material with the tunable emission of primary colors by a series of Mg1-xBaxAl2O4:Mn2+ nanopowders. Doping of manganese ion (Mn2+) in the presence of the larger barium cation (Ba2+) at tetrahedral-sites of the spinel magnesium aluminate (MgAl2O4) structure led to the creation of antisite defects. Doped samples were found to have lower bandgaps compared with MgAl2O4, and hybridization of 3d-orbitals of Mn2+ with O(2p), Mg(2s)/Al(2s3p) was found to be responsible for narrowing the bandgap. The distribution of cations at various sites at random results in a variety of electronic transitions between the valance band and oxygen vacancies as well as electron traps produced the antisite defects. The suggested compositions might be used in white light applications since they have three emission bands with centers at 516 nm (green), 464 nm (blue) and 622 nm (red) at an excitation wavelength of 380 nm. A detailed discussion to analyze the effects of the larger cationic radius of Ba2+ on the lattice strain, unit cell parameters, and cell volumes using X-ray diffraction analysis is presented.

Zirconia toughened fluorosilicate glass-ceramics for dental prosthetic restorations.

Background: Dental glass-ceramics have limited strength and are unsuitable for high-stress-bearing areas. Zirconia stands out as a popular choice for reinforcing dental glass-ceramics due to its biocompatibility and high fracture toughness. Objectives: The objective of the study is to investigate the effect of an increase in zirconia (25, 30, 35 and 50 wt%) on microstructure, chemical solubility, hardness, fracture toughness, and brittleness index of fluorosilicate glass systems for dental restorative applications. Material and methods: The fluorosilicate glass frit was obtained through the melt-quench technique. The glass frit was ball-milled with 25, 30, 35 and 50 wt % of 3 mol% yttria-stabilized zirconia (G-25Z, G-30Z, G-35Z, and G-50Z). The composites were sintered to 1000 °C for 48h at a heating rate of 5 °C/min. The glass frit was subject to differential scanning calorimetry. Phase analysis and microstructural characterization were carried out. The crystallite size of zirconia and glass-ceramics, micro-hardness, indentation fracture toughness, brittleness index, and chemical solubility were evaluated. Results: Phase analysis reveals tetragonal and monoclinic zirconia with minor peaks of forsterite, fluorphlogopite, norbergite, and spinel. Their microstructures reveal the characteristic house-of-cards arrangement of fluorophlogopite crystals with dispersed zirconia. The results of hardness and fracture toughness show a statistically significant improvement with an increase in zirconia content. The crystallite size of zirconia and fluorophlogopite crystals with aspect ratio, brittleness index, and chemical solubility declined as the zirconia content increased. Conclusions: Increase in zirconia content from 25 wt % to 50 wt % in heat-treated fluorosilicate glass systems reveals non-reactive zirconia with a stable glass matrix and limits the growth of fluorphlogopite crystals with a house-of-cards microstructure. This results in a range of properties suitable for dental restorations of enhanced hardness, and improved fracture toughness. Despite these improvements, the material maintains its machinability with reduced chemical solubility.