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Purpose: To investigate the esthetic outcomes based on the color differences in zirconia (Zr) of varying thickness, resin cement color, and types of titanium (Ti) implant surface treatments. Materials and Methods: Overall, 28 high-translucency monolithic zirconia (HTMZ) specimens were arranged into four groups based on Zr thickness: 1.0, 1.5, 2.0, and 2.5 mm (n = 7 per thickness). Each group was tested using two resin cement colors (clear and opaque) in combination with six surface-treated Ti groups (n = 7), including untreated titanium (UT), anodization (AN), 50-µm alumina airborne-particle abrasion followed by AN (SBAN), AN followed by 50-µm alumina airborne-particle abrasion (ANSB), 9.5% hydrofluoric acid followed by AN (HFAN), and AN followed by 9.5% hydrofluoric acid (ANHF). This created a total of 48 experimental groups, including the use of composite resin (n = 7, shade A2D) for four control groups. All specimens were measured using a spectrophotometer and subsequently compared with composite resin (control) with the corresponding Zr thickness to establish color differences. A color difference of < 2.7 was considered clinically acceptable. The data obtained were statistically analyzed using ANOVA and post hoc test (P = .05). Results: Zr thickness, resin cement color, and type of Ti implant surface treatment significantly affected the observed color differences (P < .05). When using 2.5-mm HTMZ with clear resin cement on AN, UT, SBAN, HFAN, and ANSB, the mean color differences were below the clinically acceptable values, and the 95% CIs of color differences were below the clinically acceptable values for AN, UT, and SBAN groups. Conclusions: HTMZ with a minimum thickness of 2.5 mm and clear resin cement on AN, UT, and SBAN groups potentially result in acceptable color matching with 95% CIs. [ABSTRACT FROM AUTHOR]

Flash sintering of ceramic powders is a complex process that involves electric, thermal and mechanical phenomena. Modelling should help to better understand and control it, with a view to producing safe and homogeneous parts. A finite element model that couples all relevant phenomena, including the densification and shrinkage of the sintering material, has been worked out for this purpose. This model is used here to investigate the flash sintering of disk-shaped parts. Particular attention is paid to the appearance and growth of heterogeneities within the part, known as hot spots, which are highly dependent on material and process parameters. Leads are provided for limiting the development of such heterogeneities. [ABSTRACT FROM AUTHOR]

The study of the raw materials used in the production of ceramic objects involves studying the materiality of the objects themselves while providing insights into the factors that guided the choice of a particular resource over another. Simultaneously, this article focuses on the social contexts in which these objects were produced. We present the results obtained through an instrumental neutron activation analysis (INAA) of ceramics from the Corral Alto site (Antofagasta de la Sierra, Catamarca) of Argentina. The results suggest that most ceramic pieces were locally manufactured, contrasting with earlier periods and coinciding with the emergence of new ways of dwelling in the Southern Argentine Puna. [ABSTRACT FROM AUTHOR]

Dislocations as line defects in crystalline solids play a crucial role in controlling the mechanical and functional properties of materials. Yet, for functional ceramic oxides, it is very difficult to introduce dense dislocations because of the strong chemical bonds. In this work, the introduction of high‐density dislocations is demonstrated by ultrahigh‐pressure sintering into a typical ceramic oxide, BiCuSeO, for thermoelectric applications. The ultrahigh‐pressure induces shear stresses that surpass the critical strength for dislocation nucleation, followed by dislocation glide and profuse multiplication, leading to a high dislocation density of ≈9.1 × 1016 m−2 in Bi0.96Pb0.04CuSeO ceramic. These dislocations greatly suppress the phonon transport to reduce the lattice thermal conductivity, reaching 0.13 Wm−1 K−1 at 767 K and resulting in a record‐high zT of 1.69 in this oxide thermoelectric ceramic. This study demonstrates the feasibility of generating dense dislocations in ceramic oxides via ultrahigh‐pressure sintering for tuning functional properties. [ABSTRACT FROM AUTHOR]

A 12-mm caliber gas gun was used to launch a high-strength steel cylindrical projectile to impact a polyurea-coated B4C ceramic target plate to investigate the effects of the polyurea coating position and the thickness of the polyurea coating on the protective ability of the ceramic composite target plate, reveal the penetration resistance mechanism of the polyurea-coated B4C ceramic plate and protection mechanism of polyurea coating. The result showed that the ceramic cone top diameter of the composite target plate coated with polyurea on the front side was 52.4–60.5% lower than that of the uncoated ceramic target plate, and the ceramic cone bottom diameter was 0.2–4% lower than that of the uncoated ceramic target plate. For the same area density, the ceramic target plate coated with polyurea on both sides had the largest percentage of mass remaining and the smallest mass of dislodged ceramic fragments. In addition, composite target plates coated with polyurea on the back side and both sides significantly reduced the head velocity of the post-target debris cloud. The polyurea coating on the front of the target plate utilizes the strain rate effect to dissipate the kinetic energy of the projectile and inhibit the spallation of ceramic fragments toward the front of the target plate. The polyurea coating on the back of the target plate utilizes bulge deformation to dissipate the kinetic energy of the projectile and intercepts the scattering of the post-target debris cloud. The polyurea coating effectively reduces ceramic target plate damage and improves composite target plate integrity level and resistance penetration. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the in vitro influence of prior silane application on the microshear bond strength (μSBS) of Scotchbond Universal Plus to glass ceramic. Materials and Methods: Thirty blocks of lithium disilicate ceramic were etched with hydrofluoric acid for 20 s and distributed into Group 1 (no silane and no adhesive), Group 2 (adhesive), Group 3 (silane + adhesive). Three cylinders of resin cement were made on each ceramic block. Five blocks (n = 15 cylinders) were subjected to the μSBS test after 24 h, and the other five blocks (n = 15 cylinders) were tested after 6 months of water storage. Results: According to two‐way ANOVA, followed by Tukey's test, the means of μSBS (MPa), denoted by different letters, show significant differences (p < 0.05): after 24 h—Group 1 (31.7)B, Group 2 (43.3)A, and Group 3 (31.3)B; after 6 months—Group 1 (14.8)B, Group 2 (33.6)A, and Group 3 (30.3)A. After 6 months of storage, there was a significant decrease in μSBS for Groups 1 and 2, along with an increase in adhesive failures across all groups. Conclusions: Prior application of silane did not increase the μSBS between Scotchbond Universal Plus and ceramic, and there was degradation at the bond interface over time. Clinical Significance: Prior application of a silane agent is not necessary when using Scotchbond Universal Plus for bonding to glass ceramics. Regardless of the prior application of silane, there is degradation at the bond interface over time. [ABSTRACT FROM AUTHOR]

Background: Two intra‐coronal preparation designs with varying extensions of cuspal coverage can perform differently regarding their fracture resistance against introral forces. Methods: Two materials (IPS e‐max CAD [EX], VITA ENAMIC [EN]), and two different preparation designs (EX‐D1), (EX‐D2), (EN‐D1), and (EN‐D2) were investigated to compare their fracture resistance. A total of 40 (n = 40) caries free human mandibular molars were used. All the prepared samples were scanned using CEREC Omnicam scanner and the preparations were checked by the software for any sharpness and undercuts before restoration designing and fabrication. All restorations were milled using Cerec MCXL 4.4 milling machine. Duo‐Link resin cement was used for cementation. After thermocycling and chewing simulation, all samples were loaded in the Universal testing machine in order to evaluate fracture resistance of all samples. Results: Fracture resistance testing revealed that e‐max CAD (2134 N) showed statistically significantly higher mean fracture resistance values than Vita Enamic (1728 N). On the other hand, there was no statistically significant difference between mean fracture resistances between the two tested designs. Conclusions: Within the confines of this investigation, it can be said that although preparation design had no appreciable impact on fracture resistance, the CAD/CAM ceramic material utilized did. Clinical Significance: When restoring compound cavitties indirectly; a conservative defect oriented approach should be used. Glass Ceramic are prefered as restorative material. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this review was to assess clinical trials that have examined the materials, design, and bonding of ceramic cantilevered resin‐bonded fixed dental prostheses (RBFDPs) as a potential option for replacing missing anterior teeth. The evaluation primarily focuses on the rate of restoration failure and clinical complications. Materials and Methods: A thorough search of databases including PubMed/MEDLINE, Scopus, and the Cochrane Library, was conducted. The most recent search was performed in October 2023. Clinical studies that compared ceramic cantilevered RBFDPs with double retainers or cantilevered RBFDPs using different ceramic materials or bonding systems were included. The outcome measures considered were restoration failure and complication rates. Results: Twelve studies met the eligibility criteria. The pooled data showed a statistically significant decrease in complication events when using cantilever designs compared with double retainer designs (p < 0.05); however, there were no differences found between the two designs in terms of restoration failure. The complication and failure rate of cantilever RBFDPs did not show a statistically significant difference with or without ceramic primer application before luting with phosphate monomer‐containing luting resin (p > 0.05). Conclusions: Ceramic cantilevered RBFDPs have lower complication rates compared with those with double retainers. The use of a ceramic primer prior to luting composite resin for ceramic cantilevered RBFDPs decreases the occurrence of complications and failures, although this effect was not statistically significant. Additional research is required to confirm these findings. Glass ceramic cantilever RBFDPs showed a decrease in success after 6 years, requiring ongoing monitoring, but both zirconia and glass‐infiltrated alumina cantilever RBFDPs have demonstrated durability with excellent long‐term success and survival rates for up to 10 and 15 years. Clinical Significance: Cantilever ceramic RBFDPs in the anterior region are a less invasive and valuable treatment option, providing good esthetic results. [ABSTRACT FROM AUTHOR]

The drawbacks of high temperature solid oxide fuel cells (HT‐SOFCs) prompt efforts to lower operating temperatures to near ambient temperatures (NAT). Here the high mixed OH−/H+ ionic conductivity in doped SrCeO3 below 100 °C is reported. The SrCe0.8Y0.2O3−δ (SCYO20) electrolyte demonstrates a high ionic conductivity of 12 mS cm−1 in water and 9 mS cm−1 in wet air at 60 °C and an excellent long‐term stability over 100 h. Solid state nuclear magnetic resonance confirms the presence of protons and hydroxide ions in the hydrated oxides and their correlation with Y dopant. Demonstration of direct ammonia fuel cells using the SCYO20 electrolyte indicates the practical application value of this material. The OH− conduction of SrCe0.7Sn0.2Y0.1O3−δ (SCSY721) is demonstrated by electrolysis of D2O. The introduction of KOH significantly increases the availability of OH− feed ions, leading to a remarkable improvement of ionic conductivity of SCSY721 electrolyte which is increased by 27 times, 56.34 mS cm−1 in 6 m KOH at 90 °C. The increased ionic conductivity due to the presence of high concentration of extrinsic conducting ions, here are OH− ions, is called as 'feeding effect'. This study offers new electrolyte materials for cost‐effective, and durable electrochemical devices such as NAT‐SOFCs. [ABSTRACT FROM AUTHOR]

Vat photopolymerization (VPP) in ceramic additive manufacturing (CAM) faces challenges due to high viscosity from ceramic powder loading, necessitating interruptive recoating steps. Ceramic particles also attenuate and divert irradiated light, causing reduced cure depth and over-curing, leading to slow print, weak interlay adhesion, and dimensional errors. This study introduces photo inhibition-aided CAM (PinCAM) using dual-wavelength digital light processing to mitigate these issues. PinCAM employs two optical masks for initiation and inhibition at different wavelengths. While previous research focused on polymers, this work evaluates inhibition's effects in suspension-based VPP-CAM. Modeling and experiments examine inhibition and curing characteristics, print speed, dimensional accuracy, surface roughness, and microstructure. Preliminary results suggest that photoinhibition has the potential to enhance geometrical and surface properties as well as particle distribution homogeneity of green ceramic components without significantly compromising print speed. Understanding inhibition's impact will aid further research in PinCAM optimization for rapid and precise ceramic manufacturing. • First systematic study on two-wavelength Photoinhibition aided Ceramic AM (PinCAM). • Modeling and characterization of inhibition and curing characteristics in PinCAM. • Pilot study on curing light and inhibition ratio effects in PinCAM speed & product. • Optimal inhibition enhances geometry, surface, density, & homogeneity of green part. • Theoretical basis & methods to establish PinCAM for advanced ceramic manufacturing. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the impact of various cleaning solutions on the geometry, roughness, gloss, hardness, and flexural strength of 3D-printed zirconia. Cleaning solutions, including isopropyl alcohol (IPA, 99.9%), ethyl alcohol (EtOH, 99.9%), and tripropylene glycol monomethyl ether (TPM, ≥ 97.5%), were diluted to a concentration of 70% and categorized into six groups: IPA99, EtOH99, TPM97, IPA70, EtOH70, and TPM70. Zirconia discs, printed via digital light processing, were sintered after cleaning. The geometry, roughness, gloss, hardness, and flexural strength were analyzed. Statistical analysis was performed using one-way ANOVA with Tukey's post hoc test (p < 0.05). The thickness of TPM70 was the highest. The diameter of TPM70 was significantly larger than that of EtOH99 and IPA70 (p < 0.05). The weight of the TPM groups was significantly higher than that of IPA70 (p < 0.05). The roughness Ra of TPM70 was significantly greater than that of IPA99, EtOH99, and EtOH70 (p < 0.05). The differences in surface gloss, hardness, and flexural strength among the different groups were not statistically significant (p > 0.05). Different cleaning solutions did not affect the surface gloss, hardness, and flexural strength of 3D-printed zirconia. High and low concentrations of the same cleaning solution did not affect the surface gloss, hardness, and flexural strength. IPA70, TPM97, and EtOH can be considered viable post-printing cleaning alternatives to the traditional gold standard, IPA99. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to determine the cutting efficiency of different diamond rotary instrument types for sectioning monolithic zirconia and lithium disilicate anatomical crowns. Materials and methods: The study used 30 diamond rotary instruments divided into three groups: Zirconia cutting diamond bur (White Z), super coarse grit diamond bur (KBlack), and medium coarse grit diamond bur (KBlue); Two subgroups were assigned based on the crown materials including monolithic zirconia (5YSZ) and lithium disilicate (e.max) ceramics. The cutting efficiency was assessed by measuring the time required to fully section the crowns, followed by scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) of the dental burs before use and after every sectioned crown. A three-way ANOVA examined the effects of bur type, material type, and sectioning stage. If interaction exists, one-way ANOVA was used to compare the different subgroups, followed by the Tukey post hoc test. The significance level was assigned at α ≤ 0.05. Results: The results exhibited various cutting efficiencies among diamond rotary instruments and ceramic crown materials. White Z demonstrated superior cutting efficiency of zirconia crown compared with KBlack and KBlue for the first cutting cycles (p ≤ 0.05); the results tend to be more comparable at the third cutting cycle. However, the super coarse diamond bur exhibited higher efficiency in cutting lithium disilicate crowns than white Z and KBlue burs through all three cutting cycles(p ≤ 0.05). The diamond bur-cutting efficiency diminished after each use, irrespective of the bur type or the crown material (p ≤ 0.05); this was represented by the reduction of carbon and increased nickel matrix ratio after each bur usage. Conclusion: White Z diamond bur showed higher cutting efficiency of zirconia in the first two cutting cycles; super coarse diamond bur is more efficient for cutting lithium disilicate crown in all of the cutting cycles. The amount of diamond on the burs reduced after each use, with no great impact on the material type when sectioning lithium disilicate and 5YSZ crowns. Clinical significance: This study provides valuable insights for dental practitioners in selecting the appropriate diamond rotary instrument for crown sectioning. Practitioners can minimize the risk of damage and reduce the time required for crown removal, improving patient outcomes. [ABSTRACT FROM AUTHOR]

Background Purpose Methods Results Conclusion In recent years, the number of hip replacement patients receiving radiation therapy has steadily increased. In parallel, strategies have been developed to reduce metal artifacts in computed tomography (CT) images and improve the accuracy of dose calculation algorithms. However, in certain situations, knowledge of the type of prosthesis material is required to accurately determine the dose distribution.This study aims to identify physical materials in hip prostheses to correctly assign them in the treatment planning system and improve dose calculation accuracy.We first verified the validity of the extended CT mass density calibration curve measured on titanium (Ti) and stainless steel (SS) metal inserts of two different diameters. Then using dedicated reference objects of various circular diameters, we developed a method based on interpolation functions to differentiate between Ti and SS material groups. Forty data sets from 18 patients were used to validate our method on two different reconstruction kernels: a standard Br44f and the electron DirectDensity (Sd40f) kernels from Siemens.Hounsfield units (HU) of Ti and SS inserts were found to vary widely depending on insert diameter, CT spectrum, and reconstruction kernels due to cupping artifacts. The largest HU difference (‐79%) was obtained for SS at 70 kV with Br44f when the diameter increased from 8 to 30 mm. Therefore, under these conditions, the extended CT‐density calibration curve is not recommended for heavy metal density determination. Using our interpolation‐based method, we achieved excellent detection (100%) and material differentiation (100%) results for stems in both reconstruction kernels. At CT energies between 110 and 140 kV, the detection and material differentiation rates were 93.3% and 92.9% for the heads and 93.3% and 92.9% for the acetabular cups, respectively, with the Br44f. Similarly, the use of Sd40f resulted in detection and differentiation rates of 94.7% and 100% for the heads and 100% and 95.0% for the acetabular cups, respectively.This method makes it possible to differentiate between hip prosthesis materials and correctly assign them to the Ti or SS group without prior knowledge of the prosthesis type, regardless of the reconstruction kernels. In combination with the Acuros XB (Varian) or Monte Carlo dose algorithms, excellent dosimetric accuracy can be achieved even in the vicinity of hip prostheses. By performing basic measurements, the method can be adapted to other CT units and reconstruction kernels, replacing the use of an extended CT‐density calibration curve. [ABSTRACT FROM AUTHOR]

The structural analysis and microwave dielectric characteristics of ionic-modified tri-rutile Ni 0·5 Sn 0·5 TaO 4 ceramics, focusing on ionic non-stoichiometry and substitution strategies, were systemically studied in this work. A tri-rutile solid solution was unequivocally identified via X-ray diffraction, Raman scatting spectra analysis, and transmission electron microscopy characterization under [110] direction. The unit cell of the tri-rutile structure experiences a contraction primarily due to the compression of the [M2O6] octahedron. An excess of Ni content and the incorporation of (Al 1/2 Nb 1/2)4+ complex cations notably halved the grain size. Conversely, deliberate Sn deficiency led to enlarged grain sizes; however, grain boundaries blurred when the deficiency exceeded 0.03 mol. The microwave dielectric properties are intricately linked to structural characteristics and sintering behavior. Ionic polarizabilities and bulk density predominantly affect the ε r value, while grain growth governs variations in the Q × f value. The distortion of [M2O6] octahedra primarily influences the τ f value. All measured τ f values demonstrated exceptional temperature stability within the range of -5 ∼ +5 ppm/°C. Notably, the Ni 0·5 Sn 0·47 TaO 4 ceramic displayed outstanding microwave dielectric characteristics: ε r = 21.9, Q × f = 45,055 GHz (at f = 10.7 GHz), and τ f = -2.07 ppm/°C post-sintering at 1425 °C, rendering it ideal for applications in extreme environmental conditions. [ABSTRACT FROM AUTHOR]

In this study, inorganic-organic coatings composed of titanium dioxide (TiO 2) as the ceramic component and poly(vinylidene fluoride- co -hexafluoropropylene) (PVDF-HFP) as the polymer matrix, hybridized with nano-TiO 2 particles, were developed for protecting mild steel (MS) from corrosion. Prior to TiO 2 coating deposition, the MS substrates were pretreated with a bioinspired sub-layer of polydopamine to improve the surface coating adhesion, followed by uniform co-deposition of PVDF-HFP with varying concentrations of embedded nano-TiO 2. The inclusion of nano-TiO 2 further reinforces and densifies PVDF-HFP, providing added corrosion protection. The fabricated coatings were characterized by microscopy, spectroscopy, and diffraction technique, while the corrosion protection properties were evaluated by impedance, potentiodynamic polarization, salt spray, and cyclic corrosion tests. Results showed that both the PVDF-HFP matrix and TiO 2 contents had substantial effects on the coatings' thermal stability, hydrophobicity, and surface mechanical properties. The coatings also exhibited satisfactory corrosion resistance, with increased impedance modulus to roughly sixteen orders of magnitude for the TiO 2 -PVDF-HFP coating containing 0.5 g/L TiO 2 , relative to the untreated MS substrate. This result can be attributed to the low surface energy of PVDF-HFP, coupled with the dense structure and added physical barrier of nano-TiO 2. Overall, these hybrid polymer/ceramic coatings are poised to help design other highly resilient and hydrophobic surface coatings with durable protection against corrosion. [ABSTRACT FROM AUTHOR]

The (Ba 0 · 95 Ca 0.05) (Ti 0 · 95 Zr 0.05) 1-x (Zn 1/3 Nb 2/3) x O 3 BCZTxZN compounds, were created using the widely adopted solid-state method. To assess the impact of (Zn, Nb: ZN) co-substitution ions we studied the structural, vibrational, and dielectric characteristics of BCZT. The phase purity was validated by conducting Rietveld refinement of XRD data, indicating the coexistence of orthorhombic and tetragonal phases at ambient temperature in the (Ba 0 · 95 Ca 0.05) (Ti 0 · 95 Zr 0.05) 0.975 (Zn 1/3 Nb 2/3) 0.025 O 3 (BCZT25ZN) composition. Furthermore, Raman spectroscopy confirmed the observed transitions. The presence of Zn2+ and Nb5+ ions resulted in a decrease in cell parameters and cell volume. The real part of the dielectric constant and the tangent loss (tan δ) exhibited values of approximately 3380 and 0.031, respectively, for the sample (Ba 0 · 95 Ca 0.05)(Ti 0 · 95 Zr 0.05) 0.95 (Zn 1/3 Nb 2/3) 0.05 O 3 (BCZT50ZN), obtained by substituting ZN in Ba 0 · 95 Ca 0 · 05 Ti 0 · 95 Zr 0 · 05 O 3. Incorporation of ZN into Ba 0 · 95 Ca 0 · 05 Ti 0 · 95 Zr 0 · 05 O 3 presents promising prospects for using the material in various device applications, including energy storage capacitors, sensors, and actuators. [ABSTRACT FROM AUTHOR]

In this study, lead-free Ba 0.85 Ca 0.15 Ti 0.95 (Nb 0.5 Yb 0.5) 0.05 O 3 (BC15TYN5) ceramic has been successfully obtained through the conventional solid-state reaction. It has been found the multifunctionality of the BC15TYN5 ceramic. It exhibits ferroelectric properties, with a significant remanent polarization value of about P r = 9.36 μC/cm2, and a recoverable energy storage density value of about W rec = 42.21 mJ/cm3. Additionally, it displays a dielectric permittivity of about ε ′ r = 7230 around T C = 80 °C, and an electro-caloric strength value of about ξ = 0.12 K mm/kV. It's worth noting that these values surpass those typically found in BaTiO 3 ceramics elaborated with similar experimental conditions. Electrical study (impedance, modulus, and conductivity characteristics) is essential for characterizing the BC15TYN5 material, determining its suitability for various technological applications, and optimizing manufacturing processes. The Cole-Cole plots exhibited two relaxations associated with the contribution of the grains and grain boundaries. The relaxation times for both grains and grain boundaries showed temperature-dependent variation following Arrhenius relation. The measured AC conductivity was evaluated by applying the Jonsher power law. Based on the thermal evolution of the exponent S , it was confirmed that the conduction mechanism follows the Correlated Barrier Hopping (CBH) model. These properties make BC15TYN5 ceramic suitable for applications such as dielectric capacitors, ferroelectric random-access memories, electrical energy storage units, and electro-caloric refrigeration systems. [ABSTRACT FROM AUTHOR]

Calcite is one of the significant components used in the wall tile application at a rate of 10–12% as its content contributes to the formation of pores. This study investigates the usability of snail shell waste with high calcium oxide content as an alternative to calcite raw material. Thus, depletion of calcite reserves will be prevented and value-added commercial products will be obtained by using waste. In addition, proper waste management will prevent environmental pollution and damage caused by waste accumulation. The chemical analysis of snail shell waste revealed a CaO content of 55%, while the CaO content in calcite was measured at 58%. Considering their similar chemical properties, different amounts of snail shell waste (%6, %9, %12) were added to the wall tile recipe instead of calcite. The addition of snail shell waste to the recipe resulted in an increase in sludge density and viscosity. Physical and mechanical tests were conducted on wall tiles made with the addition of snail shell waste and compared to standard wall tiles according to TSE EN ISO standards. When the waste material was used in a 50–50 ratio with calcite, the strength of the recipe was calculated to be 279.41 kg/cm2. Water absorption values were within standard limits and recorded at 15%. The phases that occur in the structure of wall tiles with the increase of waste addition were examined by X-ray Diffraction Analysis. The microstructures of the samples were compared with SEM–EDX analysis. Sustainable and low-cost wall tiles were obtained through the use of snail shell waste, with environmentally friendly solutions. [ABSTRACT FROM AUTHOR]

How to properly handle the high-level radionuclides cesium(Cs) and strontium(Sr) generated during the nuclear fuel cycle has become a challenging issue. Geopolymer, a novel aluminosilicate inorganic gel material, can be in-situ converted into zeolite and ceramics, exhibiting excellent immobilization capability for radioactive nuclides. This work provides a comprehensive review of the research on the conversion and synthesis methods of geopolymer into zeolite and ceramics, and conducts a detailed analysis of the performance and mechanisms of geopolymers, geopolymer-zeolite composites, and geopolymer ceramics in the immobilization of Cs and Sr. Through a thorough analysis and summary of existing literature, this study presents the optimal conditions for the conversion of geopolymers into zeolite and proposes improved methods for geopolymer ceramic immobilization of Cs. Furthermore, a comparison and analysis are conducted of the applicability, as well as the advantages and disadvantages of these three solidification matrices in immobilizing Cs and Sr. Finally, the challenges and prospects faced by geopolymer and its derivative materials in the immobilization of high-level radionuclides Cs and Sr are discussed. [ABSTRACT FROM AUTHOR]

Traditional fabrication of ceramic parts face limitations due to hardness and brittleness, despite of having good mechanical properties. Digital light processing (DLP) additive manufacturing technology offers promising way to fabricate intricate geometry of ceramic parts. To fabricate high performance, maximizing solid loading of ceramic powder is important to reduce the shrinkage and distortion during post-processing. However, it increases viscosity dramatically and makes difficult with material supply during printing process. Therefore, not only increasing the solid loading of ceramic powder but also minimizing random defects during printing process is essential for us to achieve high-quality ceramic parts. In this study, vision-based defect monitoring system using Mask R-CNN model was employed. We classified two types of defects called pinhole and un-even paste and quantify the defect characteristics such as number and size with pixel level. This method provides us the basis of a feed-back system for controlling the process parameters in real time. [ABSTRACT FROM AUTHOR]

To assess the influence of calcination process on the properties of minimally processed recycled 3Y-TZP, and to compare it with its commercial counterpart. Non-milled 3Y-TZP waste was collected, fragmented and ball-milled to a granulometric < 5 µm. Half of the recycled powder was calcined at 900 °C. Recycled 3Y-TZP disks were uniaxially pressed and sintered to create two recycled groups: 1) Calcined and 2) Non-calcined to be compared with a commercial CAD/CAM milled 3Y-TZP. The microstructure of experimental groups was assessed through density (n = 6), scanning electron microscopy (n = 3) and energy-dispersive X-ray spectroscopy (n = 3); and the crystalline content was evaluated through X-ray diffraction (XRD) (n = 3). Optical and mechanical properties were investigated through reflectance tests (n = 10), and Vickers hardness, fracture toughness (n = 5), and biaxial flexural strength tests (n = 16), respectively. Fractographic analysis was performed to identify fracture origin and crack propagation. Statistical analyses were performed through ANOVA followed by Tukey´s test, and by Weibull statistics. Particle size distribution of recycled powder revealed an average diameter of ∼1.60 µm. The relative density of all experimental groups was > 98.15 % and XRD analysis exhibited a predominance of tetragonal-phase in both recycled groups, which were similar to the crystallographic pattern of the control group. Cross-section micrographs presented flaws on the non-calcined group, and a more homogeneous microstructure for the calcined and commercial groups. Commercial samples showed lower contrast-ratio and higher translucency-parameter than the recycled groups, where non-calcined presented higher translucency-parameter and lower contrast-ratio than its calcined counterpart. The commercial group presented higher fracture toughness and characteristic strength than the recycled groups. Moreover, the calcined group exhibited higher hardness, characteristic strength, and probability of survival at higher loads than the non-calcined group. Fractographic analysis depicted the presence of microstructural flaws in the non-calcined group, which may have acted as stress-raisers and led to failures at lower flexural strengths values. The calcination process improved the microstructure, optical, and mechanical properties of the recycled 3Y-TZP. • Effect of calcination on minimally processed recycled zirconia powder was assessed. • Calcination enhanced the microstructure, optical, and mechanical features of the recycled 3Y-TZP. • Calcination did not promote alterations to the crystalline structure of the recycled 3Y-TZP. • Calcined powder resulted in a more homogeneous microstructure. • Recycled 3Y-TZP demonstrated a potential for applications in reconstructive dentistry. [ABSTRACT FROM AUTHOR]

Due to their high hardness at elevated temperatures and chemical stability, alumina-based ceramic cutting tools have been successfully applied in the machining of ferrous materials, especially quenched and tempered steels. Their low fracture toughness, however, makes it difficult to finish them by grinding, as cracks and defects can occur. In addition, its application in machining processes demands appropriate edge preparation to avoid tool failure. Within this context, the paper aims to demonstrate the applicability of an experimental Al2O3 + MgO ceramic cutting insert in hard turning. For this, grinding tests were performed to determine the most appropriate conditions to improve its surface and edge quality. The effects of cutting and feed speeds, grinding wheel bonding material, and abrasive grain size were investigated. Moreover, different cutting-edge geometries were prepared in this tool material and tested in turning a hardened AISI 4140 steel (50 HRC) to determine their performance regarding tool life and workpiece roughness. The results demonstrated that a finer grinding wheel (D15) combined with high cutting (60 m/s) and feed (10 mm/min) speeds leads to the lowest surface roughness and edge chipping. In addition, both symmetric (Κ = 1) and asymmetric (Κ = 2) edge roundings led to higher tool lives in hard turning in comparison to a single chamfered tool, as they contributed to better load distribution in the cutting region. The paper provides information for the manufacture and application of alumina-based ceramic cutting inserts in the metalworking industry, as it disseminates good manufacturing practices and recommendations for appropriate cutting-edge geometry. [ABSTRACT FROM AUTHOR]

BaAl 2 Si 2 O 8 (barium feldspar-based) materials are widely used in glass and ceramic industry due to high melting temperature, chemical resistance, low thermal expansion, low dielectric constants and attractive luminescence properties. The durability of barium feldspar ceramics strongly depends on reversible phase transitions between the low-temperature modification (celsian), and series of high-temperature (HT) polymorphs known as 'hexacelsian'. Numerous works have been devoted to the study of the thermal transitions of 'hexacelsian' by X-ray powder diffraction methods and transmission electron microscopy, the use of which provides limited information about structural changes. Here, the crystal structures, thermal properties and phase transitions of HT BaAl 2 Si 2 O 8 polymorphs are characterized for the first time using in-situ HT X-ray single-crystal structural study (SCXRD), and micro-Raman spectroscopy up to 1000 °C. The crystal structure of α-hexacelsian under ambient conditions is monoclinic (I 2/ a). The alpha-form undergoes two polymorphic transformations upon heating: into an orthorhombic (Fmmm) β-modification above 300 °C and into a hexagonal (P –62 m) γ-modification above 700 °C. These transitions lead to significant changes in the unit-cell volume: an obstacle in the production of BaAl 2 Si 2 O 8 -based ceramics. [ABSTRACT FROM AUTHOR]

The ceramic materials studied in this paper consist of finely dispersed crystalline phases embedded in a glassy matrix, which is similar to glass-ceramic materials, porcelain, and VC products. The strength depends then not only on the properties of the individual crystalline phases but also on their interactions and the matrix. Differences in mechanical properties for materials with similar chemical compositions are most likely related to diverging microstructures. Crystal orientation, grain-size distribution and shape, the ratio of the glass matrix to the crystalline phase, and homogeneity control the flexural strength of glass-ceramic materials. The subject of the study is whiteware ceramic materials from the SiO 2 –Al 2 O 3 –Na 2 O–K 2 O–MgO–SrO system, fired similarly to the regime used for VC products. The effect of the type of alkali oxide and the share of SrO were tested. This paper presents the results of hot-stage microscopy, X-ray diffraction (XRD), scanning electron microscopy with a micro-analyzer (SEM-EDS) and biaxial flexural strength measurements. Additionally, nanoindentation technique was used to access local mechanical properties. [ABSTRACT FROM AUTHOR]

Total hip arthroplasty implant choice profoundly affects survivorship, complications, and failure modes. This study evaluates the long-term (average 18 year) outcomes of ceramic-on-ceramic hip arthroplasty using uncemented shells and stems. Despite an impressive 20-year cumulative percent revision of 5.9%, the hydroxyapatite proximally coated femoral components evaluated in this study have seen declining use since 2003. A review of 349 consecutive total hip arthroplasties from 1999 to 2007 was matched to 272 cases with registry data. A survivorship analysis included 274 hips (Group A) after excluding patients lost to follow-up and navigated cases. Group B comprised 135 patients who had complete datasets spanning a minimum of 15 years. Kaplan-Meier analysis identified a 95.6% survivorship plateau at 16 to 24 years, with no significant impact from age, sex, component size, or original pathology. In Group B, EuroQol-5 Dimensions-5 Levels (EQ5D5L) scores indicated favorable outcomes in mobility, self-care, activities, pain/discomfort, and anxiety/depression, with an EQ5D visual analog score mean of 79.24. Functional scores, including the Harris Hip Score, Oxford Hip Score, and Forgotten Joint Score, showed positive outcomes. Radiologic assessments revealed no osteolysis or loose components, with a mean Engh score of 21.69. Dorr classification identified bone quality variations. Better Engh scores corresponded to higher levels of patient satisfaction. Age at surgery was correlated with better functional scores, while sex influenced various outcomes. This comprehensive study, spanning an average of 18.23 years, combined multiple patient-reported outcome measures with extensive clinical and radiologic follow-up. It reported a notably high survivorship rate for this implant combination but highlighted the declining use of the hydroxyapatite proximally coated femoral stem used in this study, potentially facing withdrawal risks in Australia. Therapeutic Level IV. [ABSTRACT FROM AUTHOR]

This paper reports the dielectric characterizations of (Ca0.95Sr0.05)(Ti1−xSnx)O3 ceramics prepared using a solid-state reaction method with various x values. X-ray diffraction spectroscopy analyses showed that the crystal structure of these pure samples was orthorhombic perovskite. With increasing Sn4+ content, the lattice constant and unit cell volume increased, while the dielectric constant decreased because of the ionic polarizability decreasing. Moreover, a maximum Q × f value of 5242 (GHz), a dielectric constant (εr) of 91.23, and a temperature coefficient (τf) of +810 ppm/°C were achieved for samples sintered at 1350 °C for 4 h. The microwave dielectric characterization was found to be strongly correlated with the sintering temperature, and the best performance was achieved for the sample sintered at 1350 °C. (Ca0.95Sr0.05)(Ti1−xSnx)O3 possesses a promising potential to be a τf compensator for a near-zero τf dielectric ceramic applied in wireless communication systems. [ABSTRACT FROM AUTHOR]

This paper presents the results of a study on the morphology, structure, and luminescent properties of ceramics synthesized in the radiation field of MeWO4 compositions (where Me is Mg, Ca, and Zn). The synthesis of ceramics was carried out by the direct action of the electron flux on an initial mixture of powders of the given stoichiometric composition. WO3, ZnO, MgO, and CaO powders with particle sizes in the range of 1–50 microns were used for the synthesis of the samples. It was found that the yield of the radiation synthesis reaction (the ratio of the mass of the sample and the charge used), when treated with an electron flux with an energy of 1.4 MeV and a flux power density of 15–18 kW/cm2, was in the range of 75–99%. The synthesis of all compositions was carried out under the same radiation treatment modes, although the melting temperatures of the starting materials varied significantly and ranged from 1473 °C (WO3) to 2825 °C (MgO). The study of the ceramic structure showed that under the radiation effect of powerful radiation fluxes on the charge, a crystalline phase of the appropriate composition formed, regardless of the synthesis modes. The results of XRD studies show that during the radiation treatment of the charge, ceramics are formed mainly with the crystalline phases ZnWO4, MgWO4, and CaWO4. These resulting MeWO4 ceramics can be used for the same purposes as crystals. Photoluminescence (PL) and cathodoluminescence (CL) were studied under excitation using stationary ultraviolet radiation and nanosecond pulses of electron flux. In general, the PL and CL of synthesized ceramic samples ZnWO4, MgWO4, and CaWO4 showed that their luminescent properties are similar to those of luminescence in corresponding crystalline materials. This indicates the formation of a crystalline phase in synthesized ceramic samples. [ABSTRACT FROM AUTHOR]

The ceramic Sr(NiNb)0.5O3, incorporating silver doping in the A site, was synthesized using a sol–gel route and subjected to comprehensive analysis through various experimental techniques. X-ray diffraction data analysis indicates a rhombohedral crystal structure. Scanning electron microscopy (SEM) examination reveals densely packed grains with minimal surface porosity. A thorough investigation of electrical properties, encompassing dielectric constant, loss tangent, electrical impedance, modulus, conductivity, etc., was conducted across a wide frequency range (103–106 Hz) and temperature range (260–340 K). This analysis provided valuable insights into structure–property relationships and conduction mechanisms. The discussion highlights the significance of interface effects, space charge polarization, and Maxwell–Wagner dielectric relaxation in achieving the material's high dielectric constant at low frequencies and elevated temperatures. Examination of temperature dependence through Nyquist plots elucidates the contributions of grain behavior to the material's resistive and capacitive properties. The dielectric permittivity, dissipation of energy, and electrical characteristics like impedance, modulus and conductivity are notably influenced by the frequency of the applied electric field and temperature. Overall, the material exhibits promising potential for industrial applications such as energy storage, given its intriguing properties. [ABSTRACT FROM AUTHOR]

The tin oxide (SnO2) varistor is a most promising pressure-sensitive material. To improve its stability in practical operation, this paper constructs a numerical simulation model of the varistor based on the Voronoi network model in computational materials science, and investigates the effect of calcium doping on its microstructure and comprehensive electrical properties. The experimental and computational results showed that the best electrical properties were obtained when the Ca doping concentration was 0.04 mol%, with an E1mA of 693 V/mm, JL of 12.3 µA/cm2, and an ɑ of 26.97. Finally, an AC accelerated aging test was performed on a sample doped with 0.04 mol% Ca (0.9 E1mA/135 °C/160 h), and the minimum value of Kt was 0.316. This study provides an experimental basis for the development of SnO2 varistors with high stability and economy. [ABSTRACT FROM AUTHOR]

When engaging in the friction stir welding of aluminum/aluminum joints, the conventional use of tools made of hard metal and steel involves a complex and costly production process. These tools experience wear over welding distances and require frequent replacement to ensure the consistency of the welded seams. The exploration of silicon nitrite as a tool material emerges as a promising alternative in this scenario. The heightened hardness of non-oxide ceramics anticipates a diminished wear rate compared to traditional welding materials, translating into an extended operational lifespan. Nevertheless, the adoption of ceramics introduces challenges initially perceived as detrimental to friction stir welding. The inherent brittleness of silicon nitrite makes it susceptible to breakage under specific loads, and thermal stresses within the component can lead to failure. To mitigate these vulnerabilities, a ceramic material with high thermal shock resistance and a low proportion of sintering additives was used. Employing these accurately designed tools friction stir welding (FSW) was performed on sheets of AA5754, followed by a comprehensive examination of their microstructural and mechanical properties. It was demonstrated that a joint efficiency of 88% can be achieved, and that an increase in hardness within the stir zone occurred as a consequence of grain refinement. Furthermore, the Portevin–Le Chatelier effect, which is characteristic of this alloy, was influenced by the FSW process. [ABSTRACT FROM AUTHOR]

The stromal vascular fraction (SVF) is a derivate of fat tissue comprising both adipose‐derived mesenchymal stem cells and endothelial cells and serves as a promising cell source for engineering vascularized bone tissues. Its combination with osteoconductive biphasic calcium phosphate (BCP) ceramic may represent a point‐of‐care agent for bone reconstruction. Here we assessed the proliferation and osteogenic differentiation capacities of SVF on 3D printed BCP implants, in comparison with isolated adipose‐derived mesenchymal stem cells (AD‐MSCs). AD‐MSCs and SVF isolated from human donors were seeded on plastic or 3D printed BCP ceramics with sinusoidal or gyroid macrotopography and cultured in the presence or absence of osteogenic factors. Vascular, hematopoietic and MSC surface markers were assessed by flow cytometry whereas osteogenic activity was investigated through alizarin red staining and alkaline phosphatase activity. Osteogenic factors were necessary to trigger osteogenic activity when cells were cultured on plastic, without significant difference observed between the two cell populations. Interestingly, osteogenic activity was observed on BCP implants in the absence of differentiation factors, without significant difference in level activity between the two cell populations and macrotopography. This study offers supportive data for the use of combined BCP scaffolds with SVF in a perspective of a one‐step surgical procedure for bone regeneration. [ABSTRACT FROM AUTHOR]

Over the past few decades, billions of adult breeding birds have been lost worldwide. The primary factors for this population loss are habitat loss and global warming. To aid the efforts for bird conservation, we have designed a simple birdhouse that can be 3D printed rapidly using a six-axis arm robot. We transformed a six-axis palletizing robotic arm into a ceramic 3D printer with the help of an extruder, stepper motor, and a custom Printed Circuit Board (PCB) consisting of an ESP32 and a motor driver. The ceramic clay is stored in a pneumatic pressure tank. An air compressor pump transports the clay from the tank to the extruder. We conducted various experiments at 8–10 bars of air pressure with different water-to-clay ratios. We found that the optimum air pressure, water-to-clay ratio, and nozzle sizes are 10 bars, 0.084, and 5 mm, respectively. After determining the appropriate printing parameters, we designed the birdhouse in the Mastercam software and generated the G-code. The G-code is loaded onto the robot controller, and the birdhouse is printed in parts. We dried the birdhouse for 24 h and then baked it in a kiln for 24 h at 1000 degrees Celsius. We then compared the ceramic birdhouse to a wooden birdhouse. The ceramic birdhouse maintains internal temperatures of 38 degrees Celsius or lower despite external temperatures reaching 43 degrees Celsius, which is on par if not better than the wooden birdhouse. This temperature will be beneficial for nesting, breeding, and egg development. [ABSTRACT FROM AUTHOR]

This in vitro study assessed the efficacy of three cleaning methods on lithium disilicate ceramic after the application of different try-in pastes through SEM analysis. Ten rectangular specimens of IPS e.max CAD were prepared using a diamond disc, crystallized, etched with 5% hydrofluoric acid, and subjected to three try-in pastes—Calibra ©, Variolink (V), RelyX Veneer®—and three cleaning techniques—air–water spray (RD), ultrasonic bath in distilled water for five minutes (ULT/W), and ultrasonic bath in distilled alcohol for five minutes (ULT/A). A control specimen was also included. After one-minute paste application and subsequent cleaning method application, SEM evaluation was conducted. The results indicate that RD was as effective as CTRL in removing remnants from R-RD, V-ULT/W and V-ULT/A samples, but ineffective for all Calibra paste-contaminated specimens. In conclusion, the optimal removal of try-in paste residues from lithium disilicate restorations is paste-dependent; however, ultrasonic baths with distilled water or alcohol proved effective for most pastes tested. [ABSTRACT FROM AUTHOR]

In recent years, laser cladding technology has been widely used in surface modification of titanium alloys. To improve the wear resistance of titanium alloys, ceramic-reinforced nickel-based composite coatings were prepared on a TC4 alloy substrateusing coaxial powder feeding laser cladding technology. Ti (C, N) ceramic was synthesized in situ by laser cladding by adding different contents (10%, 20%, 30%, and 40%) of TiN, pure Ti powder, graphite, and In625 powder. Thisestudy showed that small TiN particles were decomposed and directly formed the Ti (C, N) phase, while large TiN particles were not completely decomposed. The in situ synthetic TiCxN1−x phase was formed around the large TiN particles. With the increase in the proportion of powder addition, the wear volume of the coating shows a decreasing trend, and the wear resistance of the surface coating is improving. The friction coefficient of the sample with 40% TiN, pure Ti powder, and graphite powder is 0.829 times that of the substrate. The wear volume is 0.145 times that of the substrate. The reason for this is that with the increase in TiN, Ti, and graphite in the powder, there are more ceramic phases in the cladding layer, and the hard phases such as TiC, Ti(C, N) and Ti2Ni play the role in the structure of the "backbone", inhibit the damage caused by micro-cutting, and impede the movement of the tearing point of incision, so that the coating has a higher abrasion resistance. [ABSTRACT FROM AUTHOR]

Objectives: To assess the feasibility of producing 3D‐printed intracoronal restorations, thin and ultrathin veneers, and to compare their mechanical behavior, accuracy, biological, and stain susceptibility to the currently applied milled restorations. Materials and Methods: The databases were comprehensively searched for relevant records up to January 2024 without language restrictions. All studies that assessed 3D‐printed partial coverage restorations including inlays, onlays, laminate, and occlusal veneers were retrieved. Results: The web search yielded a total of 1142 records, with 8 additional records added from websites at a later stage. Only 17 records were ultimately included in the review. The included records compared 3D‐printed; alumina‐based‐ and zirconia ceramics, lithium disilicate ceramics, polymer infiltrated ceramics, polyetheretherketone (PEEK), resin composites, and acrylic resins to their CNC milled analogs. The pooled data indicated that it is possible to produce ultrathin restorations with a thickness of less than 0.2 mm. 3D‐printed laminate veneers and intracoronal restorations exhibited superior trueness, as well as better marginal and internal fit compared to milled restorations (p < 0.05). However, it should be noted that the choice of materials and preparation design may influence these outcomes. In terms of cost, the initial investment and production expenses associated with 3D printing were significantly lower than those of CNC milling technology. Additionally, 3D printing was also shown to be more time‐efficient. Conclusions: Using additive manufacturing technology to produce restorations with a thickness ranging from 0.1 to 0.2 mm is indeed feasible. The high accuracy of these restorations, contributes to their ability to resist caries progression, surpassing the minimum clinical threshold load of failure by a significant margin and reliable adhesion. However, before 3D‐printed resin restorations can be widely adopted for clinical applications, further improvements are needed, particularly in terms of reducing their susceptibility to stains. Clinical Significance: 3D‐printed intracoronal restorations and veneers are more time and cost‐efficient, more accurate, and could provide a considerable alternative to the currently applied CNC milling. Some limitations still accompany the resin materials, but this could be overcome by further development of the materials and printing technology. [ABSTRACT FROM AUTHOR]

A group of a well-known polychrome glazed ceramic, widespread in the western Mediterranean in the eleventh and first half of the twelfth centuries, has been analysed for the first time using Optical Microscopy (OM) and a Field Emission Scanning Electron Microscopy (FE-SEM) with Energy-Dispersive X-ray Spectroscopy (EDS), in order to shed some light on the materials, production technology and provenance, about which there are various hypotheses. This ware is characterised by a perfectly drawn and varied iconography, with often stylised zoomorphic and anthropomorphic and nautical motifs. It was produced in an as yet unidentified workshop in North Africa or the Iberian Peninsula. The pottery analysed was found in an archaeological excavation in the Barrio Andalusi of Almería (south-east of Spain). Technologically, the ceramics are fairly homogeneous, with copper-green and manganese-brown pigments applied over the raw tin glaze filled with large undissolved quartz particles. The use of quartz is consistent with a Fatimid-Zirid contribution from Ifriqiya, the use of tin is consistent with an Andalusi Umayyad-Taifas contribution, and the green and brown colours on a white ground to either Ifriqiya or Andalusi. Our study has shown that the use of quartz on the decorated glazed surface is not related to the need for an opacifier, but rather to the need for a highly viscous melt that limits the spread of the pigments during the firing allowing a finer and more detailed drawing. This fusion of different techniques has been identified for the first time. It is intriguing from the historical point of view of medieval technology, and provides the first insights into understanding the technological transfers and technical solutions that took place in the Mediterranean basin during this period. [ABSTRACT FROM AUTHOR]

Adhesively bonded cutting tools possess many advantages over classic (insert) tools due to different manufacturing processes: With reduced manufacturing temperatures, the damage to the cutting edge decreases, and the damping effects of the adhesive enhance the tool's life. In contrast to standard joining technologies like soldering, adhesive bonding enables the joining of various cutting materials and tool base bodies, like ceramic and steel. Furthermore, the usage of expensive, abrasive-resisted cutting materials, like carbide, has to be reduced in future because of the classification of the components (cobalt, wolfram carbide) as a critical resource. Therefore, this article conducts a feasibility study of adhesively bonded drills with a ceramic tip for cutting carbon-fiber-reinforced plastics. The main contents are investigations of different surface preparation methods (laser surface texturing and SACO-blasting), examining four different adhesives for cutting tool usage, and manufacturing and validating prototype drills for cutting operations. The experimental results show a high scattering of the toughness of the joints between 2.8 MPa and 27.8 MPa, depending on the combination of surface preparation and adhesives. Also, the choice of adhesive influences the performance of the manufactured drills. The maximum number of drilled holes scatters between 15 and 67 holes before breakage. A linear relation within the analysis of axial forces and factors of the covered area is observed. For further studies, the surface preparation needs to be improved, the glass transition temperature must be maximized, and the drill geometry must be optimized. Furthermore, a cooling concept for the cutting tools needs to be investigated. [ABSTRACT FROM AUTHOR]

The laser direct fusion welding of SiO 2 ceramics was a global challenge in the manufacture of radome. The paper explored the laser direct fusion welding of SiO 2 ceramics, investigated the influence of filling powder addition and welding material composition on the formation of weld. The findings revealed that the addition of welding material effectively addressed the issue of weld formation in laser direct fusion welding SiO 2 ceramic. However, the abundance of internal bubbles within the weld emerged as a significant impediment to further enhancing weld strength. The addition of SiO 2 /Al 2 O 3 mixed powder not only significantly reduced the quantity and size of internal bubbles within the weld but also generated the strengthening phase Al 2 SiO 5 , leading to a substantial increase in weld shear strength, reaching a maximum of 106 % of the base material. The research results provided a new solution for direct melting welding of ceramics. [ABSTRACT FROM AUTHOR]

Monoclinic zirconia (m-ZrO2) with the remarkable advantages of high hardness, excellent chemical stability, and heat insulation is widely used in electronic products, catalytic, and refractory materials. Here, we have systematically investigated the synthesis of m-ZrO2 nanoparticles by the hydrothermal method; the results show that in a urea–ZrO2 ratio of 2:1, 0.3 wt% Polyvinyl pyrrolidone (PVP) as an additive and a hydrothermal temperature of 180°C for 12 h, the monodispersity m-ZrO2 is successfully obtained. Furthermore, when 3% by weight m-ZrO2 was added to 3Y-ZrO2, it showed a stronger flexural strength of 325.34 MPa, which was 114.3% higher than that of 3Y-ZrO2. [ABSTRACT FROM AUTHOR]

A range of techniques for the coating of high purity alumina (HPA) on porous polypropylene battery separators has been investigated. A slurry was prepared by dispersion of the alumina powder in acetone solvent and poly (vinylidene fluoride‐co‐hexafluoropropylene) (PVdF‐HFP) as the binder to obtain an excellent adhesion to the membrane. Doctor blade, spin coating, and electro‐spin coating techniques were utilized to coat a thin layer of HPA on the separator that was followed up with a calendering step to improve compactness, decrease thickness and enhance adhesion. Furthermore, the effect of HPA particle size, distribution, and the use of a calendering step on coating thickness, compactness, and electrochemical performance were investigated using three HPA sources. The doctor blade technique was found to give the most uniform coating with the best mechanical properties and high‐temperature resistance. The coated separators were incorporated into lithium‐ion coin cells to evaluate the rate capability and long‐term cycling performance. [ABSTRACT FROM AUTHOR]

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A glass frit containing Li2O–MgO–ZnO–B2O3–SiO2 component was used to explore the low-temperature sintering behaviors and microwave dielectric characteristics of tri-rutile MgTa2O6 ceramics in this study. The good low-firing effects are presented due to the high matching relevance between Li2O–MgO–ZnO–B2O3–SiO2 glass and MgTa2O6 ceramics. The pure tri-rutile MgTa2O6 structure remains unchanged, and high sintering compactness can also be achieved at 1150°C. We found that the Li2O–MgO–ZnO–B2O3–SiO2 glass not only greatly improves the low-temperature sintering characteristics of MgTa2O6 ceramics but also maintains a high (quality factor (Q) × resonance frequency (f)) value while still improving the temperature stability. Typically, great microwave dielectric characteristics when added with 2wt% Li2O–MgO–ZnO–B2O3–SiO2 glass can be achieved at 1150°C: dielectric constant, εr = 26.1; Q × f = 34267 GHz; temperature coefficient of resonance frequency, τf = −8.7 × 10−6 /°C. [ABSTRACT FROM AUTHOR]

Abstract This study aimed to investigate the impact of various cleaning solutions on the geometry, roughness, gloss, hardness, and flexural strength of 3D-printed zirconia. Cleaning solutions, including isopropyl alcohol (IPA, 99.9%), ethyl alcohol (EtOH, 99.9%), and tripropylene glycol monomethyl ether (TPM, ≥ 97.5%), were diluted to a concentration of 70% and categorized into six groups: IPA99, EtOH99, TPM97, IPA70, EtOH70, and TPM70. Zirconia discs, printed via digital light processing, were sintered after cleaning. The geometry, roughness, gloss, hardness, and flexural strength were analyzed. Statistical analysis was performed using one-way ANOVA with Tukey’s post hoc test (p 0.05). Different cleaning solutions did not affect the surface gloss, hardness, and flexural strength of 3D-printed zirconia. High and low concentrations of the same cleaning solution did not affect the surface gloss, hardness, and flexural strength. IPA70, TPM97, and EtOH can be considered viable post-printing cleaning alternatives to the traditional gold standard, IPA99.

Abstract Background The aim of this study was to determine the cutting efficiency of different diamond rotary instrument types for sectioning monolithic zirconia and lithium disilicate anatomical crowns. Materials and methods The study used 30 diamond rotary instruments divided into three groups: Zirconia cutting diamond bur (White Z), super coarse grit diamond bur (KBlack), and medium coarse grit diamond bur (KBlue); Two subgroups were assigned based on the crown materials including monolithic zirconia (5YSZ) and lithium disilicate (e.max) ceramics. The cutting efficiency was assessed by measuring the time required to fully section the crowns, followed by scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) of the dental burs before use and after every sectioned crown. A three-way ANOVA examined the effects of bur type, material type, and sectioning stage. If interaction exists, one-way ANOVA was used to compare the different subgroups, followed by the Tukey post hoc test. The significance level was assigned at α ≤ 0.05. Results The results exhibited various cutting efficiencies among diamond rotary instruments and ceramic crown materials. White Z demonstrated superior cutting efficiency of zirconia crown compared with KBlack and KBlue for the first cutting cycles (p ≤ 0.05); the results tend to be more comparable at the third cutting cycle. However, the super coarse diamond bur exhibited higher efficiency in cutting lithium disilicate crowns than white Z and KBlue burs through all three cutting cycles(p ≤ 0.05). The diamond bur-cutting efficiency diminished after each use, irrespective of the bur type or the crown material (p ≤ 0.05); this was represented by the reduction of carbon and increased nickel matrix ratio after each bur usage. Conclusion White Z diamond bur showed higher cutting efficiency of zirconia in the first two cutting cycles; super coarse diamond bur is more efficient for cutting lithium disilicate crown in all of the cutting cycles. The amount of diamond on the burs reduced after each use, with no great impact on the material type when sectioning lithium disilicate and 5YSZ crowns. Clinical significance This study provides valuable insights for dental practitioners in selecting the appropriate diamond rotary instrument for crown sectioning. Practitioners can minimize the risk of damage and reduce the time required for crown removal, improving patient outcomes.

This paper reports the dielectric characterizations of (Ca0.95Sr0.05)(Ti1−xSnx)O3 ceramics prepared using a solid-state reaction method with various x values. X-ray diffraction spectroscopy analyses showed that the crystal structure of these pure samples was orthorhombic perovskite. With increasing Sn4+ content, the lattice constant and unit cell volume increased, while the dielectric constant decreased because of the ionic polarizability decreasing. Moreover, a maximum Q × f value of 5242 (GHz), a dielectric constant (εr) of 91.23, and a temperature coefficient (τf) of +810 ppm/°C were achieved for samples sintered at 1350 °C for 4 h. The microwave dielectric characterization was found to be strongly correlated with the sintering temperature, and the best performance was achieved for the sample sintered at 1350 °C. (Ca0.95Sr0.05)(Ti1−xSnx)O3 possesses a promising potential to be a τf compensator for a near-zero τf dielectric ceramic applied in wireless communication systems.

The Hellenistic Period mould-made bowls were a popular type of ceramic during that era. Typically hemispherical and decorated with relief on the exterior, these drinking bowls were widely used in the Mediterranean basin and the Black Sea region from the 3rd century to the mid-1st century BCE. Created as imitations of metal vessels, the bowls featured relief decorations of floral, geometric, and figurative motifs on the exterior surfaces. These bowls are divided into two main classes: Attic and Delian. Local workshops in Anatolia began producing these bowls by the late 3rd century BCE, and notable production centers included Pergamon, Sardis, Ephesus, and other cities in the region. The mould-made bowl preserved in the Kahramanmaraş Archaeology Museum was acquired through purchase. This particular bowl stands out due to its figurative scene on the wall section. It is believed to depict hoplites, Amazons (?), and the duo of Athena-Hera. These figures are organised into twelve groups, comprising a total of sixteen figures. While this bowl's figures do not have an exact parallel, it bears resemblance to Homeric bowls among the Ionian ceramics in terms of form, mythological themes, and figures. It is believed to have been produced in Ionia and likely dates between the late 3rd century and the 2nd century BCE based on its form and decoration. The detailed examination of this bowl, which is part of the Kahramanmaraş Archaeology Museum collection, is significant as it adds a new example to the corpus of Hellenistic relief bowls.

This paper presents the results of a study on the morphology, structure, and luminescent properties of ceramics synthesized in the radiation field of MeWO4 compositions (where Me is Mg, Ca, and Zn). The synthesis of ceramics was carried out by the direct action of the electron flux on an initial mixture of powders of the given stoichiometric composition. WO3, ZnO, MgO, and CaO powders with particle sizes in the range of 1–50 microns were used for the synthesis of the samples. It was found that the yield of the radiation synthesis reaction (the ratio of the mass of the sample and the charge used), when treated with an electron flux with an energy of 1.4 MeV and a flux power density of 15–18 kW/cm2, was in the range of 75–99%. The synthesis of all compositions was carried out under the same radiation treatment modes, although the melting temperatures of the starting materials varied significantly and ranged from 1473 °C (WO3) to 2825 °C (MgO). The study of the ceramic structure showed that under the radiation effect of powerful radiation fluxes on the charge, a crystalline phase of the appropriate composition formed, regardless of the synthesis modes. The results of XRD studies show that during the radiation treatment of the charge, ceramics are formed mainly with the crystalline phases ZnWO4, MgWO4, and CaWO4. These resulting MeWO4 ceramics can be used for the same purposes as crystals. Photoluminescence (PL) and cathodoluminescence (CL) were studied under excitation using stationary ultraviolet radiation and nanosecond pulses of electron flux. In general, the PL and CL of synthesized ceramic samples ZnWO4, MgWO4, and CaWO4 showed that their luminescent properties are similar to those of luminescence in corresponding crystalline materials. This indicates the formation of a crystalline phase in synthesized ceramic samples.

The thermal shock resistance of ceramics is a key factor for determining the durability of ceramic components under transient thermal conditions and is also one of the key factors for evaluating the stability of ceramics under extreme thermal conditions. After rapid heating or cooling, the surface and internal thermal stress mismatches of ceramics can cause severe thermal damage. Two main types of ceramic thermal shock exist: rapid cooling and rapid heating thermal shock. This article presents a broad understanding and insight into fundamental theory and experimental methods for ceramic thermal shock testing. The experimental equipment and procedures, test result evaluation, and material characterization of ceramic thermal shock are summarized. Moreover, outlooks and perspectives are discussed for testing and characterizing ceramic thermal shock resistance. This review will be helpful to researchers performing studies in the relevant fields of ceramics. [ABSTRACT FROM AUTHOR]

Designing dual oxideand proton-ion-conducting composite electrolytes with enhanced total ionic conductivity is essential for improving the performance of solid oxide fuel cells (SOFCs). Here, we report the impact of relative concentrations between proton and oxygen ion conducting electrolytes on the structure and electrical properties. Barium zirconate (BYZ) and samarium doped ceria (SDC) electrolytes prepared by combustion and co-precipitation method, respectively, were mixed in different ratios (0, 25, 50, 75, and 100 wt%) and sintered at 1400 °C for 6 h. X-ray diffraction studies indicate the co-existence of the perovskite and fluorite structures without the formation additional phases upon sintering. The electrochemical impedance spectra recorded under both reducing and oxidizing conditions demonstrate a reduction in grain boundary resistance of SDC with the increase in BYZ concentration. The composite with 75 % SDC and 25 % BYZ (S75B25) exhibits better conductivity in oxidizing and reducing environments with a maximum power density of 28 mW/cm2 under single-chamber SOFC conditions. The analysis of Wagner polarization results indicates an ionic transport mechanism in S75B25. Our results demonstrate the significance of dual-ion conducting composite electrolytes on improving the performance of single-chamber SOFCs. [ABSTRACT FROM AUTHOR]