Journal of the American Ceramic Society最新文献

{"title":"Mass transport in low-temperature ceramic sintering and printing assisted by pressure and water","authors":"Fan Fei,&nbsp;Xuan Song","doi":"10.1111/jace.20479","DOIUrl":"https://doi.org/10.1111/jace.20479","url":null,"abstract":"<p>Ceramic processing through the combined use of pressure and water offers a promising approach to achieve accelerated mass transport between ceramic particles at reduced temperatures, providing a sustainable and low-temperature method for ceramic synthesis and three-dimensional printing. While previous studies have explored the roles of pressure and water in the fusion and densification of ceramic particles, the underlying mechanisms, especially for micro-sized ceramic particles, are still debated. This paper aims to propose a potential mechanism for the fusion and densification of micro-sized ceramic particles under the effect of pressure and water. Using a multi-phase level-set simulation model, our results suggest that stress-assisted fracture and dissolution of interparticle contact points can be key factors driving the densification of micro-sized ceramic particles in the presence of pressure and water.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 7","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jace.20479","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143897020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular precursor pathway to Co1−xNixNb2O6 for photocatalytic dye degradation: Optical and charge transport studies","authors":"Ana Lozančić,&nbsp;Martina Vrankić,&nbsp;Marta Razum,&nbsp;Luka Pavić,&nbsp;Lidija Androš Dubraja,&nbsp;Marijana Jurić","doi":"10.1111/jace.20485","DOIUrl":"https://doi.org/10.1111/jace.20485","url":null,"abstract":"<p>A new approach for the formation of binary and ternary mixed metal oxides, namely, CoNb₂O₆, NiNb₂O₆, and Co_0.5Ni_0.5Nb₂O₆, through a modified single-source molecular precursor route was investigated. By optimizing the annealing temperature, heating/cooling rates and holding times, the phase compositions of thermal processing of mixtures of oxalate-based complexes [M(bpy)₃]₂[NbO(C₂O₄)₃]Cl·<i>n</i>H₂O (M = Co²⁺ (<b>1</b>) or/and Ni²⁺ (<b>2</b>); <i>n</i> = 11, 12) and (NH₄)₃[NbO(C₂O₄)₃]·3H₂O (<b>3</b>) were evaluated. Phase-pure columbite oxides Co₁₋<i>_x</i>Ni<i>_x</i>Nb₂O₆ (<i>x</i> = 0, 0.5, and 1) were obtained in one step by heating the mixtures of two (<b>1</b> and <b>3</b>, or <b>2</b> and <b>3</b>) or three oxalate complexes (<b>1</b> and <b>2</b> and <b>3</b>) at 1200°C for 10 h with a heating/cooling rate of 10°C min⁻¹. The (micro)structure, morphology, and optical properties of the as-prepared materials were characterized by powder X-ray diffraction (PXRD), field-emission scanning electron microscopy (FE-SEM) and ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS). Impedance spectroscopy was used to investigate the electrical and dielectric properties, providing valuable insights into the charge transport dynamics. The CoNb₂O₆ exhibits the greatest conductivity in the series (2.64 × 10⁻¹¹ Ω⁻¹ cm⁻¹ at 120°C), two orders of magnitude greater than those of NiNb₂O₆ and Co_0.5Ni_0.5Nb₂O₆. The ternary oxide Co_0.5Ni_0.5Nb₂O₆ has a minimum in conductivity and dielectric loss, but it shows a maximum in dielectric permittivity. Estimated band gap energies of CoNb₂O₆, NiNb₂O₆, and Co_0.5Ni_0.5Nb₂O₆ within the visible light excitations prompt us to investigate their photocatalytic activities in the degradation of the methylene blue (MB) dye under visible light irradiation without and with hydrogen peroxide (H₂O₂). It is evident that the Co₁₋<i>_x</i>Ni<i>_x</i>Nb₂O₆/H₂O₂ systems exhibit higher photocatalytic activity: the degradation efficiency of MB was found to be between 26% and 38%. In addition, the cyclic stability of the photocatalyst was investigated and a possible proposed photocatalytic degradation mechanism was substantiated by a scavenger analysis study.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 7","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jace.20485","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143897057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal properties of A-site and B-site co-doped rare earth zirconates","authors":"Mengyao Li,&nbsp;Zeyu Chen,&nbsp;Xuemei Song,&nbsp;Wei Zheng,&nbsp;Fan Peng,&nbsp;Yi Zeng","doi":"10.1111/jace.20492","DOIUrl":"https://doi.org/10.1111/jace.20492","url":null,"abstract":"<p>A₂B₂O₇-type rare-earth zirconates have garnered significant attention due to their low thermal conductivity. The reduction of thermal conductivity can be effectively achieved by doping with various rare earth elements at the A-site; however, there has not been a notable enhancement in the coefficient of thermal expansion. Consequently, a novel zirconate/cerate, co-doped at both the A-site and B-site, was synthesized, exhibiting lower thermal conductivity alongside a higher thermal expansion coefficient. The study of the coefficient of thermal expansion of this series of samples revealed that electronegativity and average cation radius together affect the coefficient of thermal expansion. Furthermore, thermal conductivity investigations indicated that the zirconate devoid of Ce doping retains favorable thermal conductivity across all temperatures. There is a negative correlation between thermal conductivity and mass disorder for samples other than (Nd_1/5Sm_1/5Eu_1/5Gd_1/5Lu_1/5)₂(Zr_1/2Ce_1/2)₂O₇ (HZC). HZC demonstrates a better integrated thermal performance than the other two zirconates, suggesting its potential as a new type of thermal barrier coating material with significant development prospects.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 7","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143897055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pressure-induced quenchable superhard tetrahedral amorphous phase of BC4N","authors":"Murat Durandurdu","doi":"10.1111/jace.20493","DOIUrl":"https://doi.org/10.1111/jace.20493","url":null,"abstract":"<p>The high-pressure behavior of an amorphous boron carbon nitride (BC₄N) composition is investigated using constant-pressure ab initio molecular dynamics simulations. A first-order phase transformation into a tetrahedral amorphous phase with a high fraction of sp³ bonding is observed. This tetrahedral phase is quenchable and exhibits ultra-high incompressibility and a high Vickers hardness (46 GPa), placing it firmly in the category of superhard materials, comparable to tetrahedral amorphous carbon. Tetrahedral amorphous BC₄N demonstrates semiconducting behavior with a narrow bandgap of 0.4 eV, making it suitable for applications requiring both mechanical robustness and moderate electronic conductivity. Thermodynamic analyses confirm the likelihood of a first-order sp²-to-sp³ transition, suggesting that such a transformation could occur around 29 GPa under experimental conditions.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 7","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jace.20493","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143897017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Oxidation kinetics of silicon carbide-containing refractory diborides, II: Critical assessment of permeability data for model parameters","authors":"Pavel Mogilevsky,&nbsp;Michael K. Cinibulk","doi":"10.1111/jace.20451","DOIUrl":"https://doi.org/10.1111/jace.20451","url":null,"abstract":"<p>Permeabilities of CO, H₂O, and H₂ in silica, boria, and borosilicate glasses are critical parameters in the recently revised model of oxidation of MeB₂-SiC ultra-high temperature ceramics (UHTCs). In this work, the available literature data on these parameters have been critically reviewed and evaluated. Kinetics and bubble formation during oxidation of SiC have often been discussed in the literature in relation to the relative permeation rates of O₂ and CO in silica. The analysis presented in this paper suggests that oxidation kinetics and bubble formation during the oxidation of SiC do not provide a means to quantitatively assess the permeability of CO. In combination with the semi-empirical correlations between the permeation rates, diffusivity, and solubility of other atomic and molecular gases and their atomic or molecular dimensions, the limited quantitative data on the permeability of CO in silica available in the literature were used to propose the upper and lower bounds for CO permeability and to assign tentative values to the Arrhenius parameters of its temperature dependence. No data on the permeability of CO in either boria or borosilicate glass have been found in the literature. The available literature data on the permeability of water vapor and hydrogen in silica, boria, and borosilicate glasses have been collected, compared, and critically assessed. Significant uncertainties and gaps exist in the available data on water vapor permeation rates in boria and borosilicate glasses, and no data have been found on hydrogen permeation in boria or boria-rich borosilicate glasses (above ∼14 mol% boria). Experimental measurements of CO permeability coefficients in silica, boria, and borosilicate glasses as a function of temperature and boria and water content, as well as permeability rates of water vapor in boria and borosilicate glasses, would greatly advance modeling and understanding of the environmental oxidation of this class of UHTCs and composites.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 7","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143897018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The origin of charged domains on the surface of ferroelastic BiVO4 co-doped with sodium and molybdenum","authors":"Ajay S. Pisat,&nbsp;Jackson C. Adler,&nbsp;Paul A. Salvador,&nbsp;Gregory S. Rohrer","doi":"10.1111/jace.20482","DOIUrl":"https://doi.org/10.1111/jace.20482","url":null,"abstract":"<p>Ferroelastic BiVO₄ has charged surface domains, even though its crystal structure is non-polar. These charged domains can be detected by piezo-force microscopy and lead to spatially selective photochemical reactions. The photochemical reactivity of (Bi_0.96Na_0.04)(V_0.92Mo_0.08)O₄ is studied above and below the ferroelastic transition temperature to better understand the origin of charged ferroelastic domains. The results demonstrate that spatially selective reactivity occurs above the ferroelastic transition temperature, similar to what is observed below the transition temperature. Furthermore, when the sample is cooled after brief excursions above the transition temperature, the domains reform with a microstructure that is indistinguishable from what is observed before the transition. The results are consistent with the idea that inhomogeneous distributions of charged point defects, created by stress in the ferroelastic domains, lead to charged domains that promote spatially selective photochemical reactions. If these inhomogeneous defect distributions are not homogenized above the transition temperature, they can template the re-creation of the original domain microstructure after the transformation back to the ferroelastic phase.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 7","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jace.20482","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143896877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improved grain size homogeneity, enhanced piezoelectric and mechanical properties of potassium sodium niobate-based ceramics","authors":"Xiangcheng Qi,&nbsp;Pengrong Ren,&nbsp;Xiangqian Tong,&nbsp;Lang Bian,&nbsp;Xin Wang,&nbsp;Amei Zhang,&nbsp;Hongliang Du","doi":"10.1111/jace.20483","DOIUrl":"https://doi.org/10.1111/jace.20483","url":null,"abstract":"<p>The development of high-performance potassium sodium niobate (KNN)-based piezoceramics for next-generation transducer devices is essential for a sustainable society. However, apart from remarkable piezoelectrical properties, considerable momentum should also be paid to preferable mechanical properties for the reliable operation of electronic devices. Herein, a novel three-step sintering technique is proposed in this study to modulate grain growth behavior, leading to simultaneous enhancement of piezoelectric and mechanical properties. Our research reveals that abnormal grain growth of KNN-based piezoceramic can be effectively inhibited by manipulating the thermal homogenization process at an appropriate temperature (900°C) in the first stage of the three-step sintering technology. A homogeneous grain size alleviates grain boundary stress caused by abnormal grains, inducing not only superior piezoelectric properties (piezoelectric coefficient [d₃₃] = 430 pC/N and planar electromechanical coupling factor [k_p] = 0.61) but also excellent mechanical properties (Young's modulus [E] = 161.15 GPa, nanoindentation hardness [H] = 7.56 GPa, and average compressive strength = 70.59 MPa). This work provides an effective paradigm for further optimization of both piezoelectric and mechanical properties robustness of lead-free piezoelectric ceramics for industrial applications.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 7","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143896842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermochemical compatibility and microstructure evolution of (Yb0.7Gd0.3)4Hf3O12/Yb2SiO5/Si multilayers for T/EBCs","authors":"Wangqiang Peng,&nbsp;Qian Guo,&nbsp;Liangliang Wei,&nbsp;Jian He,&nbsp;Jingyong Sun,&nbsp;Hongbo Guo","doi":"10.1111/jace.20478","DOIUrl":"https://doi.org/10.1111/jace.20478","url":null,"abstract":"<p>In this study, the novel tri-layer (Yb_0.7Gd_0.3)₄Hf₃O₁₂/Yb₂SiO₅/Si thermal/environmental barrier coatings (T/EBCs) were prepared by plasma spray-physical vapor deposition (PS-PVD) and atmospheric plasma spray. The thermochemical compatibility, microstructure evolution, phase compositions, and mechanical properties of the novel T/EBCs were systematically investigated. The (Yb_0.7Gd_0.3)₄Hf₃O₁₂ coating deposited by PS-PVD exhibited a “quasi-columnar” structure with a “feather-like” microscopic morphology, with a nanohardness of ∼3.19 GPa and an elastic modulus of ∼43.98 GPa, while the Yb₂SiO₅ coating prepared by PS-PVD had a lamellar structure with high crystallinity and low porosity. The (Yb_0.7Gd_0.3)₄Hf₃O₁₂ coating exhibited an adherent interface with the Yb₂SiO₅ coating after thermal aging at 1400°C for 100 h, with no interfacial pores or layer debonding, indicating superior thermochemical compatibility of the (Yb_0.7Gd_0.3)₄Hf₃O₁₂/Yb₂SiO₅ interface. Moreover, the (Yb_0.7Gd_0.3)₄Hf₃O₁₂ coating exhibited high resistance to sintering and great phase stability at high temperatures, making it a promising top coat material for T/EBCs.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 7","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143897002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Na2CO3–Na2SO4 corrosion resistance of mullite castables","authors":"Chunfeng Liu,&nbsp;Guoqing Xiao,&nbsp;Cailian Chen,&nbsp;Biqiang Xie,&nbsp;Donghai Ding,&nbsp;Changkun Lei,&nbsp;Christopher Parr,&nbsp;Christoph Wöhrmeyer","doi":"10.1111/jace.20463","DOIUrl":"https://doi.org/10.1111/jace.20463","url":null,"abstract":"<p>Mullite castables, employed as the lining materials in high-salinity organic waste liquids incinerators, are subjected to severe alkali attack. The alkali corrosion resistance of four types of mullite castables based on Mullite60 (M60), Mullite45 (M45), Fire clay (FC), and Glass-rich mullite (GRM) materials, named CM60, CM45, CFC, and CGRM respectively, was investigated using a static crucible testing method with Na₂CO₃ and Na₂SO₄ under 1100°C in this study. The results showed that CGRM demonstrated exceptional resistance to Na₂CO₃ and Na₂SO₄. Among these four kinds of mullite materials, GRM stood out as it not only contained 54 wt.% of mullite but also unique glass phase that filled in the voids of the interwoven mullite crystals. The glass phase within the GRM aggregates provided a protective barrier against severe alkali corrosion for the mullite crystals by maintaining an adequate liquid phase. This liquid phase filled the micropores, resulting in an extremely dense corrosion layer. The high content and viscosity of the liquid phase formed within the CGRM matrix during alkali attack further impeded penetration, thereby CGRM exhibited good resistance to alkaline slag corrosion. However, the mullite phase in the aggregates of M60, M45, and FC was vulnerably corroded by the alkali due to lack of enough glass phase. This then led to the formation of corrosion products including nepheline, lazurite, and Na_1.65Al_1.65Si_0.35O₄, which induced internal stress and finally resulted in the surface cracking of the crucibles. Moreover, the presence of cristobalite in CM45 and CFC promoted the cracks propagation due to phase transformation. The large pores and cracks within the FC aggregates exacerbated the alkali corrosion in CFC. Therefore, GRM materials containing glass-rich liquid phase have great application prospects in mullite castables for enhancing resistance to alkaline slags.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 7","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143897015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predicting photopolymer resin pyrolysis kinetics in ceramic vat photopolymerization additive manufacturing","authors":"Eoin G. McAleer,&nbsp;Joseph Prati,&nbsp;John M. Matthewson,&nbsp;Richard A. Haber,&nbsp;Enver Koray Akdoğan","doi":"10.1111/jace.20470","DOIUrl":"https://doi.org/10.1111/jace.20470","url":null,"abstract":"<p>The kinetics of polymers pyrolysis, particularly those containing ethoxylated trimethylolpropane triacrylate ((EtO)₃-TMTPA), is of utmost importance in optimizing the binder removal process that is associated with ceramic vat photopolymerization (CerVPP). Here, we focus on the decomposition kinetics of a simplified resin, which is a photopolymer system that is formulated from (EtO)₃-TMTPA and a photoinitiator (diphenyl(2,4,6-trimethylbenzoyl) phosphine oxide). The thermal behavior of the resin was critically assessed with the use of thermogravimetric analysis (TGA) under atmospheric pressure in a flowing argon gas atmosphere. The Fraser‒Suzuki function was used to deconvolve the TGA peaks in conjunction with nonlinear regression that was based on a finite difference solution of the nonlinear rate equation. From this analysis, pertinent kinetic parameters were obtained. The variation of the kinetic parameters was studied as a function of heating rate. The resulting model allowed for the prediction of thermal decomposition behavior of CerVPP resins for a representative, simulated, yet practical heating rate program. This prediction was compared to TGA measured resin decomposition using the same heating rate program. The model's predictions accurately identified the two primary apparent reaction steps displayed in the differential TGA data.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 7","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jace.20470","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143897085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}