International Journal of Applied Ceramic Technology最新文献

Ceramic tile manufacturing faces increasing pressure to cut energy use and reliance on virgin raw materials. Here, soda-lime waste glass was evaluated as a partial replacement for feldspar flux in tile bodies under industrially relevant processing. Five formulations containing 0–20 wt.% waste glass were produced via wet milling, granulation, two-stage uniaxial pressing, and fast firing in an industrial roller kiln (peak 1177°C; total 53 min). Thermal behavior, phase evolution, microstructure, and properties were assessed by DTA/TG, XRD, SEM/EDS, and standardized tests. Waste glass promoted earlier liquid-phase formation, increased vitrification, and lowered porosity under fast-firing conditions. The optimal composition was 15 wt.% glass, leading to the best densification balance with low water absorption (2.83%), reduced open porosity (4.97%), controlled linear shrinkage (7.99%), and high flexural strength (∼61 MPa). XRD showed decreasing crystallinity with increasing glass and albite formation, attributed to sodium diffusion from the glassy phase, consistent with the denser microstructure. This study demonstrates waste-glass fluxing in an industrial fast-firing roller kiln, defines a practical composition-property window at fixed firing temperature, and connects thermal, phase, microstructural, and performance changes. Soda-lime waste glass is therefore a scalable flux for energy-efficient, circular-economy ceramic tile production.

Ceramic tile manufacturing faces increasing pressure to cut energy use and reliance on virgin raw materials. Here, soda-lime waste glass was evaluated as a partial replacement for feldspar flux in tile bodies under industrially relevant processing. Five formulations containing 0–20 wt.% waste glass were produced via wet milling, granulation, two-stage uniaxial pressing, and fast firing in an industrial roller kiln (peak 1177°C; total 53 min). Thermal behavior, phase evolution, microstructure, and properties were assessed by DTA/TG, XRD, SEM/EDS, and standardized tests. Waste glass promoted earlier liquid-phase formation, increased vitrification, and lowered porosity under fast-firing conditions. The optimal composition was 15 wt.% glass, leading to the best densification balance with low water absorption (2.83%), reduced open porosity (4.97%), controlled linear shrinkage (7.99%), and high flexural strength (∼61 MPa). XRD showed decreasing crystallinity with increasing glass and albite formation, attributed to sodium diffusion from the glassy phase, consistent with the denser microstructure. This study demonstrates waste-glass fluxing in an industrial fast-firing roller kiln, defines a practical composition-property window at fixed firing temperature, and connects thermal, phase, microstructural, and performance changes. Soda-lime waste glass is therefore a scalable flux for energy-efficient, circular-economy ceramic tile production.

Intergranular fracture due to the penetration of metal dendrites is an important failure mode in inorganic solid electrolytes (ISEs). Adequate fracture resistance at ISE grain boundaries (GBs) is thus critical for realizing practical solid-state batteries (SSBs). Using a machine learning (ML) technique, this work connects attributes of ISE GBs to their fracture resistance and demonstrates that GBs in distinct materials, by virtue of their local structure and composition, can behave in similar ways. Altering interfacial characteristics is thus suggested as a potential method for tuning material properties without changing crystal chemistry. We train a mixture-of-experts (MoE) based ML model for estimating work of adhesion (W_ad), the thermodynamic threshold energy for fracture, at ISE GBs and construct structure maps using latent features extracted from the model. A global picture of GB W_ad across ISE chemistries is thus presented and complex relationships between crystallographic attributes of GBs, their local non-stoichiometry, and W_ad are revealed. While this ML-assisted technique may provide useful insights for processing ISEs with higher fracture-resistance by tuning GB chemistry, it also highlights the value in analyzing latent variables from ML models for unraveling complex structure-property relationships.

Over the past 50 years, the sol–gel process has advanced both scientifically and technologically. In this review, the process as applied to silicates is examined with a focus on its successes and its potential for further implementation. The emphasis is on applications, rather than basic science. At times, the product is identified explicitly as being a sol–gel processed material. In other cases, sol–gel processing is inferred based on the precursors and is one of many steps in producing the product.

A modified sol–gel method using β-cyclodextrin as a template was used to synthesize apatite-type lanthanum and praseodymium silicate supports for Ni-loaded ethanol steam reforming catalysts. The effects of nonionic Brij 58 surfactant addition and the substitution of lanthanum with praseodymium on the properties of catalysts were studied. Thermal decomposition of the sample precursor gels was investigated by thermal analysis coupled with evolved gas mass spectrometry. The samples were analyzed by XRD, EDX, low-temperature nitrogen physisorption, temperature-programmed reduction with H₂, XPS, oxygen isotope exchange with C¹⁸O₂, and tested in the ethanol steam reforming.

A modified sol–gel method using β-cyclodextrin as a template was used to synthesize apatite-type lanthanum and praseodymium silicate supports for Ni-loaded ethanol steam reforming catalysts. The effects of nonionic Brij 58 surfactant addition and the substitution of lanthanum with praseodymium on the properties of catalysts were studied. Thermal decomposition of the sample precursor gels was investigated by thermal analysis coupled with evolved gas mass spectrometry. The samples were analyzed by XRD, EDX, low-temperature nitrogen physisorption, temperature-programmed reduction with H₂, XPS, oxygen isotope exchange with C¹⁸O₂, and tested in the ethanol steam reforming.

This work reports a one-pot green synthesis of reduced graphene oxide (RGO) from graphene oxide (GO) using Calendula officinalis mother tincture as a natural reducing and stabilizing agent. Taken together, a bathochromic shift with a broad absorption band cantered near 305 nm in UV–Vis; attenuation of carbonyl and C–O bands and stronger sp² C = C features in FTIR; disappearance of the GO (001) low-angle XRD peak at 11.9° and the emergence of a graphitic (002) peak at 26.4° for RGO; and increased ID/IG ratio from 0.832 to 1.08 and a shift of weak 2D features band from 2694 to 2678 cm⁻¹ in Raman for RGO implies partial restoration of the sp2 conjugated network and confirmed successful reduction. Furthermore, a smoother, compact, and restacked sheet-like microstructure of RGO in FESEM and TEM analyses provides compelling evidence for the successful reduction of GO to RGO. Finally, in vitro biological performance of RGO was evaluated through antibacterial assays against Bacillus subtilis and Escherichia coli; cytocompatibility, proliferation by using L929 cells; and hemocompatibility. Overall, C. officinalis acts as both a green reductant and functionalizing agent that can effectively produce hemocompatible, antimicrobial, and cytocompatible RGO with promising therapeutic potential.

Zinc aluminate spinel (ZnAl₂O₄, gahnite) is gaining importance as a spinel component in the alumina spinel refractory castables due to its excellent thermo-mechanical and chemical properties. The present work investigates the effect of the amount of in situ formed ZnAl₂O₄ spinel on the properties of cement-bonded high-alumina castable. ZnO was added in the castable composition at 4.4, 6.6, and 8.8 wt.% to form 10, 15, and 20 wt.% in situ ZnAl₂O₄ spinel, respectively. The castable compositions were processed through conventional technique and heat treated at 110°C, 1000°C, and 1550°C. They were then characterized for various refractory properties, namely, bulk density, apparent porosity, strength at ambient and elevated temperatures, phase analysis, and microstructural study. The optimum ZnAl₂O₄-containing composition was further characterized for resistance against thermal shock and slag corrosion. The evaluated properties were compared against a high-alumina castable (without ZnO), used as a reference. The results show that 10 wt.% in situ ZnAl₂O₄ spinel-containing castable has the optimum properties. The properties indicate that the Al₂O₃‒ZnAl₂O₄ spinel castables can substitute Al₂O₃‒MgAl₂O₄ spinel castables, especially for iron and steel industry applications.

This work reports a one-pot green synthesis of reduced graphene oxide (RGO) from graphene oxide (GO) using Calendula officinalis mother tincture as a natural reducing and stabilizing agent. Taken together, a bathochromic shift with a broad absorption band cantered near 305 nm in UV–Vis; attenuation of carbonyl and C–O bands and stronger sp² C = C features in FTIR; disappearance of the GO (001) low-angle XRD peak at 11.9° and the emergence of a graphitic (002) peak at 26.4° for RGO; and increased ID/IG ratio from 0.832 to 1.08 and a shift of weak 2D features band from 2694 to 2678 cm⁻¹ in Raman for RGO implies partial restoration of the sp2 conjugated network and confirmed successful reduction. Furthermore, a smoother, compact, and restacked sheet-like microstructure of RGO in FESEM and TEM analyses provides compelling evidence for the successful reduction of GO to RGO. Finally, in vitro biological performance of RGO was evaluated through antibacterial assays against Bacillus subtilis and Escherichia coli; cytocompatibility, proliferation by using L929 cells; and hemocompatibility. Overall, C. officinalis acts as both a green reductant and functionalizing agent that can effectively produce hemocompatible, antimicrobial, and cytocompatible RGO with promising therapeutic potential.

Zinc aluminate spinel (ZnAl₂O₄, gahnite) is gaining importance as a spinel component in the alumina spinel refractory castables due to its excellent thermo-mechanical and chemical properties. The present work investigates the effect of the amount of in situ formed ZnAl₂O₄ spinel on the properties of cement-bonded high-alumina castable. ZnO was added in the castable composition at 4.4, 6.6, and 8.8 wt.% to form 10, 15, and 20 wt.% in situ ZnAl₂O₄ spinel, respectively. The castable compositions were processed through conventional technique and heat treated at 110°C, 1000°C, and 1550°C. They were then characterized for various refractory properties, namely, bulk density, apparent porosity, strength at ambient and elevated temperatures, phase analysis, and microstructural study. The optimum ZnAl₂O₄-containing composition was further characterized for resistance against thermal shock and slag corrosion. The evaluated properties were compared against a high-alumina castable (without ZnO), used as a reference. The results show that 10 wt.% in situ ZnAl₂O₄ spinel-containing castable has the optimum properties. The properties indicate that the Al₂O₃‒ZnAl₂O₄ spinel castables can substitute Al₂O₃‒MgAl₂O₄ spinel castables, especially for iron and steel industry applications.