Open Ceramics最新文献_第6页

Effect of crystalline Si3N4 fillers on the mechanical strength and thermal stability of complex SiCN(O) ceramic architectures produced by powder bed fusion and densified via polymer infiltration and pyrolysis 结晶Si3N4填料对粉末床熔合、聚合物渗透和热解致密复合SiCN(O)陶瓷结构机械强度和热稳定性的影响

IF 2.8 Q1 MATERIALS SCIENCE, CERAMICS

Open Ceramics

Pub Date : 2025-12-01 Epub Date: 2025-09-13 DOI: 10.1016/j.oceram.2025.100846

Marco Pelanconi , Samuele Bottacin , Mario Caccia , Alberto Ortona , Yawei Li

Silicon nitride is a high-performance ceramic recognized for its mechanical, thermal, and chemical stability at elevated temperatures. In this study, we present a novel method to fabricate macroporous Si₃N₄ ceramics via powder bed fusion of polyamide mixed with 0-40 vol% of crystalline Si₃N₄ powder. The printed preforms were subsequently infiltrated with a polysilazane polymer and pyrolyzed to form SiCN(O) matrices containing β-Si₃N₄ particles. A rotated cube lattice was selected as a benchmark geometry and scaled to compensate for shrinkage. The effects of ceramic filler content on densification, microstructure, strength, and oxidation resistance at 1500 °C were investigated. Increasing β-Si₃N₄ content improved the relative density, compressive strength, and thermal stability of the final ceramics. Particularly, 20–40 vol% Si₃N₄ enhanced oxidation resistance by forming a protective silica-rich surface layer and stabilizing the underlying structure. This study highlights an effective strategy to tailor the high-temperature behaviour of polymer-derived ceramics for advanced structural applications.

氮化硅是一种高性能陶瓷，因其在高温下的机械、热和化学稳定性而得到认可。在这项研究中，我们提出了一种新的方法，通过将聚酰胺与0-40体积%的结晶Si₃N₄粉末混合的粉末床熔融来制备大孔Si₃N₄陶瓷。随后，用聚硅氮烷聚合物浸润打印的预成型物，并热解形成含有β-Si₃N₄颗粒的SiCN(O)基质。选择旋转的立方体晶格作为基准几何，并缩放以补偿收缩。研究了填料含量对合金致密化、显微组织、强度和1500℃抗氧化性能的影响。增加β-Si₃N₄的含量，提高了陶瓷的相对密度、抗压强度和热稳定性。特别是，20-40 vol% Si₃N₄通过形成保护性的富硅表面层和稳定底层结构来增强抗氧化性。这项研究强调了一种有效的策略来定制聚合物衍生陶瓷的高温行为，用于先进的结构应用。

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引用次数: 0

Incorporation of Zn/Sr-Ga based LDH particles into Si-HAp coatings to control the corrosion of Nitinol alloys 在Si-HAp涂层中加入Zn/Sr-Ga基LDH颗粒控制镍钛诺合金的腐蚀

IF 2.8 Q1 MATERIALS SCIENCE, CERAMICS

Open Ceramics

Pub Date : 2025-12-01 Epub Date: 2025-09-24 DOI: 10.1016/j.oceram.2025.100852

Reza Samiee , Alicia Duran , Yolanda Castro , Dusan Galusek , A.R. Boccaccini , Amirhossein Pakseresht

Metallic implants, especially Nitinol, have numerous biomedical applications; however, they have inherent drawbacks, such as poor corrosion and wear resistance and suffer from nickel ion leaching. To address these challenges, this paper explores the use of silicon-substituted hydroxyapatite (Si-HAp) coatings with incorporated Zn/Sr-Ga based Layered Double Hydroxide (LDH) particles deposited by electrophoretic deposition (EPD). The synthesized Zn/Sr-Ga based LDH particles were investigated as both passive and active fillers in Si-HAp coatings. An anodization pre-treatment of the Nitinol substrates was performed to improve adhesion between the substrate and the coating. The EPD parameters were also optimized to prepare homogeneous and stable Si-HAp coatings loaded with Zn/Sr-Ga LDH particles. The morphology, composition, and electrochemical properties of the Si-HAp composite coatings were characterized using different techniques. Electrochemical impedance spectroscopy (EIS) and polarization studies demonstrated a significant improvement of the corrosion resistance properties of Si-HAp coatings with Zn/Sr-Ga LDH particles, compared to pure Si-HAp coatings and Nitinol substrate. The LDH@Si-HAp-coated sample showed the lowest nickel release, indicating the potential of LDH to reduce toxicity and enhance the strength of Nitinol implants.

金属植入物，特别是镍钛诺，有许多生物医学应用；然而，它们有固有的缺点，如耐腐蚀性和耐磨性差，并遭受镍离子浸出。为了解决这些挑战，本文探索了硅取代羟基磷灰石（Si-HAp）涂层的使用，该涂层采用电泳沉积（EPD）沉积Zn/Sr-Ga基层状双氢氧化物（LDH）颗粒。研究了合成的Zn/Sr-Ga基LDH颗粒作为Si-HAp涂层的被动填料和主动填料。对镍钛诺基板进行了阳极氧化预处理，以改善基板与涂层之间的附着力。优化了EPD参数，制备了均匀稳定的负载Zn/Sr-Ga LDH颗粒的Si-HAp涂层。采用不同的技术对Si-HAp复合涂层的形貌、组成和电化学性能进行了表征。电化学阻抗谱（EIS）和极化研究表明，与纯Si-HAp涂层和镍钛诺基体相比，添加Zn/Sr-Ga LDH颗粒的Si-HAp涂层的耐腐蚀性能有显著提高。LDH@Si-HAp-coated样品的镍释放量最低，表明LDH具有降低镍钛诺植入物毒性和增强其强度的潜力。

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引用次数: 0

Effects of different NaOH concentrations to synthesize CuO NPs for the tuning of properties 不同NaOH浓度对合成CuO NPs性能的影响

IF 2.8 Q1 MATERIALS SCIENCE, CERAMICS

Open Ceramics

Pub Date : 2025-12-01 Epub Date: 2025-09-28 DOI: 10.1016/j.oceram.2025.100856

Sumaiya Akter , Md․Saiful Alam , Sumaya Tabassum , Dipa Islam , Md․Najem Uddin , Sanjida Khan , Samina Ahmed , Md. Sahadat Hossain

CuO NPs are a remarkable transitional metal oxide species that are a potential photocatalytic and antimicrobial agent for wastewater treatment, though they exhibit considerable limitations that restrict their practical applications. The current study aims to alter the structural properties of CuO by implementing different reducing agent concentrations and to enhance its functional properties as well. The characteristic evaluation of the prepared specimens was executed by implementing X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDAX). The data obtained from XRD peaks were utilized to determine intrinsic specifications, including crystallite size, texture coefficient, preference growth, etc., to track the change in microstructural characteristics, which proclaimed a significant shift in these parameters was achieved with different reducing agent concentrations. Morphological probing by SEM delineated the alteration in the average size and shape of the specimens from spherical towards cylindrical shape. The specimens showed comparatively enhanced photocatalytic dye degradation percentage and biocidal activity as synthesized at higher reducing agent concentration under the examined conditions.

CuO NPs是一种重要的过渡金属氧化物，是废水处理中潜在的光催化和抗菌剂，尽管它们具有相当大的局限性，限制了它们的实际应用。本研究旨在通过施加不同的还原剂浓度来改变氧化铜的结构性质，并增强其功能性质。采用x射线粉末衍射（XRD）、热重分析（TGA）、傅里叶变换红外（FTIR）、扫描电子显微镜（SEM）和能量色散x射线分析（EDAX）对制备的样品进行了特征评价。利用x射线衍射峰的数据，确定了晶体尺寸、织构系数、偏好生长等内在指标，跟踪了微观结构特征的变化，发现不同还原剂浓度下，这些参数发生了显著变化。扫描电镜形态学探测表明，样品的平均尺寸和形状由球形向圆柱形转变。在所考察的条件下，在较高的还原剂浓度下合成的样品具有较强的光催化染料降解率和生物杀灭活性。

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引用次数: 0

Microstructure and adsorption studies on the simultaneous removal of Cu2+, Ni2+, and Zn2+ from simulated wastewater using magnetically functionalized Philippine natural zeolite composite 磁性功能化菲律宾天然沸石复合材料同时去除模拟废水中Cu2+、Ni2+和Zn2+的微观结构和吸附研究

IF 2.8 Q1 MATERIALS SCIENCE, CERAMICS

Open Ceramics

Pub Date : 2025-12-01 Epub Date: 2025-09-09 DOI: 10.1016/j.oceram.2025.100845

Belinda B. Faustino , Reynaldo M. Vequizo , Rolando T. Candidato Jr.

This study reports the microstructural characteristics and adsorption properties for heavy metal ions of the surface-modified Philippine natural zeolite (MPNZ) and magnetically functionalized Philippine natural zeolite (PNZM) composite. SEM analysis confirmed the presence of magnetite particles dispersed on PNZM, making its surface rougher and irregular while retaining its porous structure. X-ray diffractogram revealed distinct peaks corresponding to the spinel crystalline structure of magnetite and the aluminosilicate structure of the zeolite framework, suggesting a well-integrated composite material. BET analysis showed an increase in the surface area of MPNZ from 33.876 m²/g to 45.052 m²/g after adding magnetite. EDS characterization verified the strong presence of Fe⁺ ions in the PNZM structure, enhancing its cation-exchange capacity (CEC). The Si/Al ratio of MPNZ decreased from 3.75 to 3.37, indicating a more negative charge, supported by zeta potential results that showed surface charges of (-)12.200 for MPNZ to (-) 20.854 mV for PNZM. In single ion solutions, PNZM obtained a removal uptake of 98.85 %, 99.99 % and 99.48 % for Ni²⁺, Cu²⁺and Zn²⁺ respectively, which are higher than MPNZ. In mixed-ion solutions, PNZM also showed improved adsorption with removal rates of 91.17 % for Ni²⁺ and 97.90 % for Cu²⁺, although Zn²⁺ uptake decreased to 97.98 % compared to the 99.99 % of MPNZ. Overall, incorporating magnetite has functionalized the ability of PNZM for sustainable water treatment by removing heavy metal ions through the synergistic mechanism of ion-exchange and Coulombic electrostatic interactions.

研究了表面改性菲律宾天然沸石（MPNZ）和磁功能化菲律宾天然沸石（PNZM）复合材料的微观结构特征和对重金属离子的吸附性能。SEM分析证实，PNZM表面存在分散的磁铁矿颗粒，使其表面更加粗糙和不规则，同时保留了其多孔结构。x射线衍射图显示磁铁矿尖晶石晶体结构和沸石骨架铝硅酸盐结构相对应的明显峰，表明复合材料具有良好的整体性。BET分析表明，加入磁铁矿后，MPNZ的比表面积由33.876 m2/g增加到45.052 m2/g。EDS表征证实了PNZM结构中Fe+离子的存在，增强了其阳离子交换能力（CEC）。MPNZ的Si/Al比值从3.75下降到3.37，表明MPNZ具有更多的负电荷，zeta电位结果表明MPNZ的表面电荷为（-）12.200 mV， PNZM的表面电荷为（-）20.854 mV。在单离子溶液中，PNZM对Ni2+、Cu2+和Zn2+的去除率分别为98.85%、99.99%和99.48%，均高于MPNZ。在混合离子溶液中，PNZM对Ni2+的去除率为91.17%，对Cu2+的去除率为97.90%，而Zn2+的去除率为97.98%，而MPNZ的去除率为99.99%。总的来说，加入磁铁矿使PNZM通过离子交换和库仑静电相互作用的协同机制去除重金属离子，从而功能化了PNZM可持续水处理的能力。

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引用次数: 0

Phase relations in the Sm2O3-Fe2O3 system: Structure and magnetic properties of perovskite SmFeO3 ceramics Sm2O3-Fe2O3体系中的相关系：钙钛矿SmFeO3陶瓷的结构和磁性能

IF 2.8 Q1 MATERIALS SCIENCE, CERAMICS

Open Ceramics

Pub Date : 2025-12-01 Epub Date: 2025-10-18 DOI: 10.1016/j.oceram.2025.100866

O.V. Chudinovych , T.V. Tomila , V.G. Kolesnichenko , A.V. Samelyuk , D.V. Vedel , A. Lynnyk

The phase relations in the Sm₂O₃–Fe₂O₃ system at 1300 and 1400 °C were studied in the whole concentration range by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The samples were prepared with a concentration step of 1–5 mol %. The isothermal cross-sections of the Sm₂O₃–Fe₂O₃ phase diagram at 1300 and 1400 °C are characterized by the presence of four single-phase (B–Sm₂O₃, SmFeO₃(R), Sm₃Fe₅O₁₂, Fe₂O₃), three two-phase (B–Sm₂O₃+SmFeO₃, SmFeO₃+ Sm₃Fe₅O₁₂, Sm₃Fe₅O₁₂+Fe₂O₃) regions. The refined lattice parameter of the unit cell and the boundaries of the homogeneity fields for solid solutions were determined. The range of homogeneity of solid solutions based on the R-phase extends from 49 to 52 mol % Sm₂O₃ at 1300 and 1400 °C. Nanocomposites based on the perovskite phase (SmFeO₃) were obtained by the Pechini method and heterogeneous precipitation from nitrate solutions. The influence of the production method on the microstructure, morphology, and magnetic properties of nanopowders (SmFeO₃) was studied. According to XRD, infrared spectroscopy, SEM, the synthesized perovskite SmFeO₃ is single-phase with a particle size of 50–60 nm. The morphology of powder particles primarily depends on the method of material synthesis. The powders display superparamagnetic-like loops at 300 K, typical of nanoparticle ensembles.

采用x射线衍射仪（XRD）和扫描电镜（SEM）研究了Sm2O3-Fe2O3体系在1300℃和1400℃全浓度范围内的相关系。样品以1-5 mol %的浓度步骤制备。Sm2O3-Fe2O3相图在1300℃和1400℃时的等温截面表现为存在4个单相区（B-Sm2O3, SmFeO3(R), Sm3Fe5O12, Fe2O3）， 3个两相区（B-Sm2O3 +SmFeO3, SmFeO3+ Sm3Fe5O12, Sm3Fe5O12+Fe2O3）。确定了单元胞的精细化晶格参数和固溶体均匀场的边界。在1300和1400℃时，r相固溶体的均匀性范围为49 ~ 52 mol % Sm2O3。采用Pechini法和非均相沉淀法从硝酸溶液中制备了基于钙钛矿相（SmFeO3）的纳米复合材料。研究了制备方法对纳米粉末（SmFeO3）微观结构、形貌和磁性能的影响。通过XRD、红外光谱、SEM分析，合成的钙钛矿SmFeO3为单相，粒径为50 ~ 60 nm。粉末颗粒的形貌主要取决于材料合成的方法。粉末在300 K时显示出超顺磁性的环状结构，这是典型的纳米颗粒系综。

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引用次数: 0

Enhancing densification of metakaolin-based geopolymers via the cold sintering process 利用冷烧结工艺提高偏高岭土聚合物的致密性

IF 2.8 Q1 MATERIALS SCIENCE, CERAMICS

Open Ceramics

Pub Date : 2025-12-01 Epub Date: 2025-10-09 DOI: 10.1016/j.oceram.2025.100863

Abdullah Jabr , Srečo D. Škapin , Sara Tominc , Nina Daneu , Jakob König , Vilma Ducman , Lidija Korat Bensa , Raul Bermejo , Matjaž Spreitzer

Clay-based materials typically require high-temperature processing (>900 °C), resulting in high energy consumption. This study explores cold sintering of metakaolin (MK) powders to achieve high mechanical strength at significantly lower processing temperatures. By applying uniaxial pressure of 400 MPa and heating to only 240 °C in the presence of 15 mol/L NaOH solution, successful densification of structurally sound and dense samples with an average density of 2.16 g/cm³ and a biaxial flexural strength of ∼35 MPa was achieved. This strength surpasses that of conventionally sintered MK (1470 °C) by ∼30 %. Densification was found to be governed by synergistic mechanisms involving MK exfoliation, conformal sintering around aggregates, and the precipitation of an amorphous sodium aluminosilicate hydrate phase. Crack formation was avoided through process optimization and verified using X-ray micro-computed tomography. These findings offer new insights into the chemo-mechanical mechanisms of cold sintering and demonstrate its potential as an efficient route for producing structural materials.

粘土基材料通常需要高温处理（>900°C），导致高能耗。本研究探讨了偏高岭土（MK）粉末的冷烧结在显著降低的加工温度下获得高机械强度。通过施加400 MPa的单轴压力，在15 mol/L NaOH溶液存在下加热至240℃，成功致密化了结构良好且致密的样品，平均密度为2.16 g/cm³，双轴抗弯强度为~ 35 MPa。这种强度比传统烧结的MK（1470°C）高出约30%。发现致密化是由协同机制控制的，包括MK剥离，聚集体周围的保形烧结和无定形水合硅酸铝钠相的沉淀。通过工艺优化避免了裂纹的形成，并通过x射线微计算机断层扫描进行了验证。这些发现为冷烧结的化学力学机制提供了新的见解，并证明了其作为生产结构材料的有效途径的潜力。

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引用次数: 0

Advanced shaping of diverse ceramic materials via dental CNC technology: A sustainable strategy for high-precision machining of green and brown bodies 通过牙科数控技术对各种陶瓷材料进行高级成形：绿色和棕色体高精度加工的可持续策略

IF 2.8 Q1 MATERIALS SCIENCE, CERAMICS

Open Ceramics

Pub Date : 2025-12-01 Epub Date: 2025-11-04 DOI: 10.1016/j.oceram.2025.100877

Dagmara Uhl , Tamanna Thakur , Oskar Waldemar Ausobsky , Natalia Kovalska , Luc Conti , Mahmoud Hadad , Dariusz Kata , Gurdial Blugan

This study presents a comprehensive investigation into the development of machinable brown ceramic bodies with compact five-axis CNC machining systems. Green body disc formation, pre-sintering protocols, and machining parameters were systematically refined to achieve enhanced dimensional precision and surface quality. The coordinated design improvement of powder dosing, packing density, pressing pressure, and pre-sintering temperature produced ceramic blanks with mechanical properties well-suited for stable and accurate machining. By lowering pre-sintering temperatures, the brittleness of brown bodies was reduced, enabling smoother cutting, minimized tool wear, and improved structures. Using this approach, complex geometries with sub-millimeter wall thicknesses (300–350 μm) were successfully machined with high accuracy. Sintered TZ-3YSB-E and ZTA ceramics demonstrated flexural strengths of 837 MPa and 483 MPa, respectively, alongside excellent thermal conductivity and machinability. The findings support the development of robust, efficient machining strategies for next-generation ceramic components with complex geometries.

本文对采用紧凑的五轴数控加工系统开发可加工的棕色陶瓷体进行了全面的研究。为了提高尺寸精度和表面质量，系统地改进了绿体盘的形成、预烧结方案和加工参数。通过对粉末用量、填充密度、压紧压力和预烧结温度的协调设计改进，生产出具有稳定和精确加工性能的陶瓷毛坯。通过降低预烧结温度，降低了棕色体的脆性，实现了更平滑的切削，最大限度地减少了刀具磨损，并改善了结构。利用这种方法，可以高精度地加工出亚毫米壁厚（300-350 μm）的复杂几何形状。烧结后的TZ-3YSB-E和ZTA陶瓷的抗折强度分别为837 MPa和483 MPa，具有优异的导热性和可加工性。研究结果支持开发具有复杂几何形状的下一代陶瓷部件的强大，高效的加工策略。

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引用次数: 0

Effects of flash-calcined sediment on the mechanical – microstructural development and the durability of cementitious materials against to chloride attack and leaching 闪烧泥沙对胶凝材料力学微观结构发育及抗氯化物侵蚀和浸出耐久性的影响

IF 2.8 Q1 MATERIALS SCIENCE, CERAMICS

Open Ceramics

Pub Date : 2025-12-01 Epub Date: 2025-10-18 DOI: 10.1016/j.oceram.2025.100868

Mouhamadou Amar , Mahfoud Benzerzour , Duc Chinh Chu , Nor-Edine Abriak , Joelle Kleib

Numerous studies have highlighted the beneficial effects of flash-calcined sediment (SF) substitution on the mechanical performance of materials. However, very few studies have investigated its impacts on durability, especially the leaching. This study aims to assess its potential effects on the mechanical-microstructural development as well as durability against chloride ingress and leaching. The results indicate that the high specific surface area of SF accelerates cement hydration at early ages, while its pozzolanic reactivity contributes to an enhancement of compressive strength and microstructure in SF-based mortar (MSF) in the long term compared to the reference mortar (Mref). In addition, the formation of addition C-S-H gels from the pozzolanic reaction and the reduction in the critical diameter of pores explain the improved resistance of MSF mortar to chloride penetration. The leaching reveals a significant enhancement in the durability of SF-based cement paste, demonstrated by lower quantities of leached elements and reduced degradation depth compared to the reference. These benefits are attributed to lower Ca(OH)₂ content, a reduced Ca/Si ratio in C–S–H, and a refined microstructure in the MSF paste, which strongly hinder ion diffusion. The dissolution of hydrates during leaching also leads to a decrease in the Young’s modulus of hydration products, and degradation of the microstructure. However, the SF incorporation significantly mitigates this effect compared to the reference.

许多研究都强调了闪烧沉积物（SF）替代对材料力学性能的有益影响。然而，很少有研究调查其对耐久性的影响，特别是对浸出的影响。本研究旨在评估其对机械微观结构发展以及抗氯化物侵入和浸出的耐久性的潜在影响。结果表明：与参考砂浆（Mref）相比，SF基砂浆（MSF）的高比表面积在早期加速了水泥的水化，而其火山灰反应性则有助于提高MSF的抗压强度和微观结构。此外，火山灰反应生成的加成C-S-H凝胶和临界孔径的减小解释了MSF砂浆抗氯离子渗透性能的提高。浸出表明，与参考材料相比，sf基水泥浆的耐久性显著提高，浸出元素的数量减少，降解深度降低。这些好处归因于较低的Ca(OH) 2含量，C-S-H中Ca/Si比的降低，以及MSF膏体中精细的微观结构，这强烈阻碍了离子的扩散。浸出过程中水合物的溶解也会导致水化产物杨氏模量的降低和微观结构的破坏。然而，与参考文献相比，SF的合并显著地减轻了这种影响。

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引用次数: 0

Thermal properties of porous ceramics 多孔陶瓷的热性能

IF 2.8 Q1 MATERIALS SCIENCE, CERAMICS

Open Ceramics

Pub Date : 2025-12-01 Epub Date: 2025-10-18 DOI: 10.1016/j.oceram.2025.100867

Siddhartha Roy

As porous ceramics are attractive materials for different high-temperature applications, such as thermal insulators, high-temperature filters, porous burners, etc., a thorough understanding of their thermal properties is crucial. Among different thermal properties, while the melting points and coefficients of thermal expansion are independent of porosity, thermal conductivity, thermal shock resistance, and thermal fatigue resistance strongly depend upon the selection of the bulk ceramic, amount of porosity, and different pore characteristics such as pore shape and size, pore connectivity and anisotropy, etc. In this review paper, a thorough description of the different structural and physical characteristics controlling the thermal properties of porous ceramics has been provided, along with a critical analysis of the published experimental results. Finally, some potential directions for future research on the thermal properties of porous ceramics have been identified.

由于多孔陶瓷是不同高温应用的有吸引力的材料，例如隔热材料，高温过滤器，多孔燃烧器等，因此彻底了解其热性能至关重要。在不同的热性能中，熔点和热膨胀系数与孔隙率无关，导热系数、热冲击性能和热疲劳性能在很大程度上取决于本体陶瓷的选择、孔隙率的多少以及不同的孔隙特征，如孔隙形状和大小、孔隙连通性和各向异性等。在这篇综述文章中，对控制多孔陶瓷热性能的不同结构和物理特性进行了全面的描述，并对已发表的实验结果进行了批判性分析。最后，对多孔陶瓷热性能的研究方向进行了展望。

引用次数: 0

High-resolution tomographic analysis of microstructure and porosity in mock-ups of ancient-inspired mosaics 古代镶嵌画模型中微观结构和孔隙度的高分辨率层析分析

IF 2.8 Q1 MATERIALS SCIENCE, CERAMICS

Open Ceramics

Pub Date : 2025-12-01 Epub Date: 2025-09-30 DOI: 10.1016/j.oceram.2025.100859

Neva M.E. Stucchi , Gianluca Iori , Philipp Hans , Andrea Vavasori , Giulia Franceschin , Arianna Traviglia

This research investigates the use of Synchrotron X-ray Computed Tomography (SXCT) to study Roman mosaic mock-ups, focusing on the three-dimensional distribution of material density, cracks, and stress-strain interactions across layers. Three samples were analysed: one of stone tesserae and two of glass tesserae. High-resolution SXCT scans, using polychromatic radiation at X-ray energies above 70 keV, enabled non-invasive, microscale examination of cracks and assessment of how composition influences crack development at interfaces. Digital reconstruction and phase contrast analysis distinguished cracks from pores, revealing microstructural features and enabling quantification of pore volumes and porosity variations within strata. The results showed that stone tesserae induced more extensive cracking in the Supra Nucleus stratum than glass tesserae. These findings enhance understanding of internal microstructure and stress behaviour in mosaics, providing a basis for developing appropriate conservation strategies. Quantifying fracture dimensions enables conservators to determine the optimal viscosity and formulation of consolidants for effective penetration and stabilization, while insights on compaction and tesserae surface quality inform the design of re-adhesion and cleaning protocols that enhance cohesion and minimize future detachment. Together, these results show how microscale analysis can guide material selection and treatment strategies, ultimately supporting more durable repairs and the long-term preservation of mosaics.

本研究利用同步加速器x射线计算机断层扫描（SXCT）研究罗马马赛克模型，重点研究材料密度、裂缝和应力-应变相互作用的三维分布。对三个样品进行了分析：一个是石镶嵌，两个是玻璃镶嵌。高分辨率SXCT扫描，使用70 keV以上的x射线能量的多色辐射，可以对裂缝进行非侵入性的微尺度检查，并评估成分如何影响界面处的裂缝发展。数字重建和相对比分析区分了裂缝和孔隙，揭示了微观结构特征，并实现了地层孔隙体积和孔隙度变化的量化。结果表明，石镶嵌比玻璃镶嵌在上核层中引起更广泛的开裂。这些发现增强了对马赛克内部微观结构和应力行为的理解，为制定适当的保护策略提供了基础。通过对裂缝尺寸的量化，保护人员可以确定最佳的黏度和固结剂配方，从而实现有效的渗透和稳定，同时，对压实和tesserae表面质量的了解，可以为重新粘接和清洁方案的设计提供信息，从而增强粘聚力，最大限度地减少未来的脱落。总之，这些结果显示了微尺度分析如何指导材料选择和处理策略，最终支持更持久的修复和马赛克的长期保存。

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