Cement and Concrete Research最新文献_第5页

CO2 uptake in calcium aluminosilicate materials 钙铝硅酸盐材料对CO2的吸收

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2025-10-11 DOI: 10.1016/j.cemconres.2025.108056

Subhashree Panda , Luis Schnürer , Alisa Machner , Luis Ruiz Pestana , Prannoy Suraneni

CO₂ mineralization has gained increasing attention as a strategy to reduce emissions from concrete production. This study investigates the carbonation potential of several calcium aluminosilicate (CAS) materials, model systems for understanding supplementary cementitious materials (SCMs). CAS materials were synthesized at temperatures ranging from 1000 °C to 1600 °C, producing structures ranging from partially crystalline to fully amorphous. X-ray diffraction and scanning electron microscopy were used to understand material physicochemical properties. Carbonation potential was assessed through CO₂ uptake measurements using thermogravimetric analysis and Fourier-transform infrared spectroscopy, while SCM reactivity was evaluated via a modified R³ test. Results show that materials synthesized at 1000 °C and 1200 °C, containing unreacted oxides, portlandite, CA, and C₂S, exhibited the highest CO₂ uptake but the lowest reactivity as SCM. In contrast, fully amorphous glasses synthesized at 1600 °C demonstrated significantly higher SCM reactivity but minimal CO₂ uptake. These findings highlight a fundamental trade-off between their reactivity and carbonation potential, governed by the degree of amorphization.

二氧化碳矿化作为一种减少混凝土生产排放的策略越来越受到关注。本研究探讨了几种硅酸铝钙（CAS）材料的碳化潜力，作为理解补充胶凝材料（SCMs）的模型系统。合成CAS材料的温度范围从1000℃到1600℃，产生的结构范围从部分结晶到完全非晶。利用x射线衍射和扫描电镜了解材料的物理化学性质。通过使用热重分析和傅里叶变换红外光谱测量CO2吸收来评估碳化势，而通过改进的R3测试来评估SCM的反应性。结果表明，在1000°C和1200°C合成的含未反应氧化物、硅酸盐、CA和C2S的材料，作为SCM的CO2吸收量最高，但反应性最低。相比之下，在1600°C下合成的全非晶玻璃显示出明显更高的SCM反应性，但二氧化碳吸收最小。这些发现强调了它们的反应性和碳酸化潜力之间的基本权衡，这是由非晶化程度决定的。

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引用次数: 0

Influence of FRP rebar polymer matrix leachates on cement hydration and bond performance in FRP-reinforced concrete 玻璃钢钢筋聚合物基质浸出液对玻璃钢混凝土水泥水化及粘结性能的影响

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2025-10-10 DOI: 10.1016/j.cemconres.2025.108051

Amir Behravan , Cooper Davenport , Emily Spradley , B. Dulani Dhanapala , Bernard Kassner , Stephen Sharp , Alyson Daniels

Fiber-reinforced polymer (FRP) rebars are increasingly used in construction due to their advantages over conventional steel reinforcement. However, well-established standards and design codes for all FRP types remain limited. While most previous studies have focused on the mechanical bond between FRP rebars and concrete, this study provides a detailed investigation of how organic compounds leached from FRP rebars affect cement hydration kinetics and, consequently, bond performance. Ten different FRP rebars—including glass (GFRP), basalt (BFRP), and carbon (CFRP) types—were examined. Analytical techniques such as total organic carbon (TOC), ICP-MS, and FTIR confirmed the leaching of organic compounds from the rebars. Subsequent experiments using isothermal calorimetry, SEM, and mechanical testing assessed how these leachates influence cement hydration in the vicinity of the rebars. The results indicate that specific organic compounds from the polymer matrix can negatively affect hydration in the transition zone, reducing the quality of the interfacial bond between FRP rebars and the cementitious matrix. These findings highlight the importance of chemical interactions at the FRP–concrete interface and suggest that both improvements to the rebar surface and modifications to the concrete mixture should be considered. Given the variability among different FRP rebars, a single universal design guideline may not be sufficient for all products.

纤维增强聚合物（FRP）钢筋由于其优于传统钢筋的优点而越来越多地应用于建筑中。然而，所有FRP类型的完善标准和设计规范仍然有限。虽然之前的大多数研究都集中在FRP筋与混凝土之间的机械结合上，但本研究提供了从FRP筋中浸出的有机化合物如何影响水泥水化动力学，从而影响结合性能的详细调查。研究了10种不同的FRP筋，包括玻璃（GFRP）、玄武岩（BFRP）和碳（CFRP）。总有机碳（TOC）、ICP-MS和FTIR等分析技术证实了钢筋中有机化合物的浸出。随后的实验使用等温量热法、扫描电镜和力学测试来评估这些渗滤液如何影响钢筋附近的水泥水化。结果表明，来自聚合物基体的特定有机化合物会对过渡区水化产生负面影响，降低FRP筋与胶凝基质之间的界面结合质量。这些发现强调了frp -混凝土界面化学相互作用的重要性，并建议应考虑改进钢筋表面和修改混凝土混合物。考虑到不同FRP筋之间的可变性，单一的通用设计准则可能不足以适用于所有产品。

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引用次数: 0

Carbonation behavior of Portland cement incorporating polycarboxylate ether superplasticizer: Towards carbonation kinetics, microstructural evolution and mechanical properties 掺聚羧酸醚减水剂硅酸盐水泥的碳化行为：碳化动力学、微观结构演变和力学性能研究

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2025-10-10 DOI: 10.1016/j.cemconres.2025.108061

Jionghuang He , Guangcheng Long , Yi Jiang , Qinglong Qin , Cong Tang , Yong Tao , Peiliang Shen , Chi-Sun Poon

Polycarboxylate ether (PCE) superplasticizers are crucial in modern concrete, yet their compatibility with carbonation curing, a promising CO₂ sequestration method, remains insufficiently understood. This study systematically examined carbonation behavior of Portland cement (PC) incorporating PCE by analyzing its phase assemblage, microstructure, carbonation heat, solution chemistry and mechanical properties. Results indicated that PCE significantly reduced the carbonation rate. The peak rate of carbonation heat in pure PC reached 0.57 W/g, while the addition of 2.0 % PCE reduced this value by 43.9 %. This reduction was attributed to the adsorption and complexation effects of PCE, the immobilization of CaCO₃ clusters within polymer network, as well as a rapid decrease in solution pH. Furthermore, the aggressive carbonation kinetics amplified the detrimental impact of PCE on microstructural development. This inhibited carbonation at particle boundaries and weakened interparticle bonding, thereby leading to a decline in mechanical performance. These findings offer fundamental insights into the compatibility and limitations of using PCE in combination with carbonation technologies in concrete.

聚羧酸醚（PCE）高效减水剂在现代混凝土中至关重要，但它们与碳化固化（一种很有前途的二氧化碳封存方法）的相容性仍未得到充分了解。本研究通过分析PCE硅酸盐水泥的相组合、微观结构、碳化热、溶液化学和力学性能，系统地考察了PCE硅酸盐水泥的碳化行为。结果表明，PCE显著降低了碳酸化速率。纯PC的碳化热峰值为0.57 W/g，而添加2.0%的PCE使碳化热峰值降低了43.9%。这种减少归因于PCE的吸附和络合作用、CaCO3簇在聚合物网络中的固定化以及溶液ph的快速降低。此外，积极的碳化动力学放大了PCE对微观结构发育的有害影响。这抑制了颗粒边界的碳化，削弱了颗粒间的结合，从而导致机械性能下降。这些发现为PCE与混凝土碳化技术结合使用的兼容性和局限性提供了基本的见解。

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引用次数: 0

Sulfate adjustment and early reactivity in cements containing kaolinitic calcined clays: investigation and assessment via a sulfate-limited model system 硫酸盐调节和含高岭石煅烧粘土的水泥的早期反应性：通过硫酸盐限制模型系统的研究和评估

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2025-10-10 DOI: 10.1016/j.cemconres.2025.108060

Tafadzwa Ronald Muzenda , Yannick Demeusy , Fabien Georget , Christophe Labbez , Thomas Matschei

Understanding the early reaction kinetics of calcined clays (CCs) in calcined clay-limestone cements (CCLC) is required to optimize the formulations for optimal early performance. In this study, a clinker-free sulfate-limited model system (SLiM) is utilized to compare the early reactivity of 9 diverse natural CCs. The SLiM consists of an excess of CC and portlandite, and limited gypsum It is demonstrated that the sulfate-carrier depletion time provides a rate of reaction for each clay which is characteristic of its reactivity in a blended cement. As such, it is shown that the SLiM test can be used to probe physico-chemical properties, including the standard enthalpy of formation of metakaolinite, and to understand the mechanical performance and hydration of blended cement with these clays up to 3 days. In conclusion, a foundation for a standard test allowing to adjust gypsum content in CCLC from a single calorimetry measurement is developed.

了解煅烧粘土（CCs）在煅烧粘土-石灰石水泥（CCLC）中的早期反应动力学是优化配方以获得最佳早期性能的必要条件。本研究采用无熟料硫酸盐限制模型系统（SLiM）比较了9种不同天然cc的早期反应性。SLiM由过量的CC和波特兰硅酸盐和有限的石膏组成。硫酸盐载体耗尽时间为每种粘土提供了反应速率，这是混合水泥中其反应性的特征。因此，SLiM测试可以用于探测偏高岭石的物理化学性质，包括标准形成焓，并了解这些粘土混合水泥的力学性能和水化作用长达3天。总之，开发了一个标准测试的基础，允许调整CCLC中的石膏含量，从单一的量热法测量。

引用次数: 0

Clinoptilolite zeolite as a substrate for alkali-boosting cement hydration 斜沸石作为底物对水泥的碱促水化作用

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2025-10-10 DOI: 10.1016/j.cemconres.2025.108057

M. Shariful Islam , Joseph J. Biernacki , Benjamin J. Mohr

Clinoptilolite-Ca zeolite exhibited limited pozzolanic activity at early ages in portland cement systems, resulting in slower initial hydration and strength development. Conversion of Ca-zeolite to Na- or K-forms, combined with increasing the pH of the blended system through pH engineering of the treated zeolite, substantially enhanced its reactivity. Calorimetry revealed accelerated C₃S and C₃A hydration, with higher peak intensities and shorter dormancy periods for Na-or-K zeolites, whereas bulk portlandite analysis indicated that Ca-zeolite inhibits clinker reactions. Phase-resolved quantitative EDS confirmed these trends, showing retardation of hydration for Ca-zeolite and promotion of both silicate and aluminate phases reactions for Na-and K-zeolites, along with the formation of relatively higher amounts of AFm phases. Chemical shrinkage and mortar strength measurements further supported these findings. Notably, pH-engineered zeolites increased early-age strength by up to 10 %, with 7-days mortar strength remaining equivalent even at 20 % cement replacement, highlighting their potential as sustainable supplementary cementitious materials.

斜沸石-钙沸石在硅酸盐水泥体系早期表现出有限的火山灰活性，导致初始水化和强度发展较慢。将ca型沸石转化为Na型或k型沸石，再加上通过处理沸石的pH工程提高混合体系的pH值，大大提高了其反应性。量热分析表明，na -或k型沸石能加速C₃S和C₃A的水化反应，其峰值强度更高，休眠时间更短，而硅酸盐分析表明，ca型沸石能抑制熟料反应。相分辨定量EDS证实了这些趋势，表明ca -沸石的水化反应迟缓，而na -沸石和k -沸石的硅酸盐和铝酸盐相反应促进，同时形成相对较多的AFm相。化学收缩和砂浆强度测量进一步支持了这些发现。值得注意的是，ph工程沸石将早期强度提高了10%，即使在20%的水泥替代下，7天砂浆强度仍保持不变，这凸显了它们作为可持续补充胶凝材料的潜力。

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引用次数: 0

Accelerated carbonation fronts in cement pastes: Mechanistic insights and simplified modeling 水泥浆体中的加速碳化前沿：力学见解和简化建模

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2025-10-09 DOI: 10.1016/j.cemconres.2025.108050

Luge Cheng , Ryo Kurihara , Zhenli Yang , Takahiro Ohkubo , Ryoma Kitagaki , Atsushi Teramoto , Yuya Suda , Ippei Maruyama

This study investigated the carbonation behavior of ordinary Portland cement (OPC), volcanic glass powder (VGP), and limestone-calcined clay cement (LC³) pastes, focusing on the water content distribution, phase assemblages, and microstructural evolution. Spatiotemporal changes in water and mineral phases were tracked using proton nuclear magnetic resonance relaxometry and micro-X-ray diffraction, respectively. A simplified model reproduced the drying front, defined by a material-specific threshold water content, which aligned closely with the experimentally measured carbonation front. This confirmed that carbonation progression is governed by water diffusion, referred to as the “plugging effect”. Furthermore, carbonation advanced until empty space increased to approximately 18 %, resulting from the decalcification-induced agglomeration of calcium (alumino) silicate hydrate (C–(A)–S–H). This limit was consistently observed across pastes with varying Ca/(Si + Al) ratios. These findings provide mechanistic insight into carbonation front development and offer a physically grounded criterion for predicting carbonation depth and assessing CO₂ uptake in sustainable cementitious materials.

本研究研究了普通硅酸盐水泥（OPC）、火山玻璃粉（VGP）和石灰石煅烧粘土水泥（LC3）的碳化行为，重点研究了其含水量分布、相组合和微观结构演变。利用质子核磁共振弛豫仪和微x射线衍射分别跟踪了水相和矿物相的时空变化。一个简化的模型再现了干燥锋，由特定材料的阈值含水量定义，这与实验测量的碳化锋密切相关。这证实了碳酸化过程是由水扩散控制的，称为“堵塞效应”。此外，由于脱钙引起的水合硅酸钙（铝）团聚（C - (A) - s - h），碳化作用继续推进，直到真空空间增加到约18%。这一极限在不同Ca/(Si + Al)比例的膏体中一致观察到。这些发现为碳酸化前沿的发展提供了机理见解，并为预测碳酸化深度和评估可持续胶凝材料的CO 2吸收提供了物理基础标准。

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引用次数: 0

Quantifying reactivity of secondary materials as cement substitutes: Modifications to strength activity index methodology 量化作为水泥替代品的二次材料的反应性：对强度活性指数方法的改进

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2025-10-08 DOI: 10.1016/j.cemconres.2025.108055

Taohua Ye , Jianzhuang Xiao , Zihan Zhou , Tongbo Sui

Strength activity index (SAI) testing often serves as the benchmark for other reactivity tests, such as the rapid, relevant, and reliable (R³) test. However, the flaws in the SAI methodology compromise its accuracy. In this study, the SAI test is revisited and intensively modified by decoupling SCM physicochemical effects and mitigating the influence of SCM density and water sorption. The modified SAI test is validated using quartz powder (QP) and six secondary materials, including fly ash (FA), ground granulated blast furnace slag (GGBFS), recycled concrete powder (RCP), carbonated RCP (CRCP), and thermoactivated RCP (T650 and T750). The results of the modified SAI test closely align with those of the simplified R³ test (R² > 0.90), confirming the reactivity ranking: GGBFS ≈ FA > T750 ≈ T650 > CRCP > RCP ≈ QP. Moreover, the application conditions of the modified SAI test are also identified. In summary, this study contributes to reliable reactivity quantification to support appropriate SCM utilization in cementitious systems.

强度活度指数（SAI）测试通常作为其他反应性测试的基准，如快速、相关和可靠（R3）测试。然而，SAI方法的缺陷损害了其准确性。在本研究中，通过解耦SCM的物理化学效应，减轻SCM密度和吸水率的影响，对SAI测试进行了重新审视和深入修改。采用石英粉（QP）和粉煤灰（FA）、磨粒高炉渣（GGBFS）、再生混凝土粉（RCP）、碳化RCP （CRCP）和热活化RCP (T650和T750) 6种二次材料进行了改良SAI试验。改良SAI试验结果与简化R3试验结果接近（R2 > 0.90），确定了反应性排序：GGBFS≈FA >； T750≈T650 > CRCP > RCP≈QP。此外，还确定了改进后的SAI试验的适用条件。总之，这项研究有助于可靠的反应性量化，以支持在胶凝体系中适当使用SCM。

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引用次数: 0

Autogenous shrinkage mitigation effect of superabsorbent polymers on alkali-activated GGBFS-FA binary binder without additional water: performance, microstructure and mechanism 不加水的高吸水性聚合物对碱活化GGBFS-FA二元粘结剂的自收缩减缓作用：性能、微观结构及机理

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2025-10-08 DOI: 10.1016/j.cemconres.2025.108058

Beifeng Lv , Lizhong Wang , Qiang Zeng , Hengyu Liu , Yujie Li , Zhen Guo

This work seeks to explore the mechanisms of superabsorbent polymers (SAP) in mitigating autogenous shrinkage of an alkali-activated ground granulated blast furnace slag-fly ash (GGBFS-FA) binary binder through elaborate microstructural analysis. The effect patterns of SAP with different dosages (0–0.5 %) and particle sizes (91–631 μm) on the setting time, workability, mechanical strength and autogenous shrinkage were tested. Porosity, pore size distribution, specific surface area, and chemical characteristics were systematically explored. Results revealed that 0.5 % SAP interrupted capillary stress through pore coarsening, thereby reducing autogenous shrinkage by 80 % (3266.57 to 637.89 με). Smaller SAP particle (91 μm) enhanced water release efficiency and promoted calcium silicoaluminate hydrate (C-(A)-S-H) gel formation, while larger SAP particle (631 μm) delayed water release and improved strength with slower shrinkage stabilization. The findings on the water release characteristics and pore coarsening mechanism of SAP deepen our understanding of autogenous shrinkage controls in alkali-activated materials (AAM).

本研究旨在通过详细的微观结构分析，探索高吸水性聚合物（SAP）在减轻碱活性粉状高炉渣-粉煤灰（GGBFS-FA）二元粘结剂自收缩中的作用机制。考察了SAP添加量（0 ~ 0.5%）和粒径（91 ~ 631 μm）对凝固时间、和易性、机械强度和自收缩的影响规律。系统地探讨了孔隙度、孔径分布、比表面积和化学特性。结果表明，0.5% SAP通过孔隙粗化打断毛管应力，使自收缩率降低80% （3266.57 ~ 637.89 με）。较小的SAP颗粒（91 μm）提高了水的释放效率，促进了水合硅铝酸钙（C-(A)- s - h）凝胶的形成，而较大的SAP颗粒（631 μm）延迟了水的释放，提高了强度，收缩稳定速度较慢。碱活化材料的释水特性和孔隙粗化机理的研究结果加深了我们对碱活化材料（AAM）自收缩控制的认识。

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引用次数: 0

Diffusion and physicochemical behavior of chloride and sodium ions in C-S-H gel pores : A molecular dynamics investigation 氯离子和钠离子在C-S-H凝胶孔隙中的扩散和物理化学行为：分子动力学研究

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2025-10-04 DOI: 10.1016/j.cemconres.2025.108053

Tarek Ihaddadene, Jérôme Claverie, François Bignonnet, Ouali Amiri

Calcium silicate hydrate (C-S-H) gel is an amorphous material with a complex, disordered structure that complicates the understanding of its atomic-scale properties. While many studies have investigated ionic diffusion in C-S-H pores, the behavior of sodium (

) and chloride (

) ions, particularly in relation to the Ca/Si ratio, is not well understood. In this study, atomistic models of C-S-H were developed with varying Ca/Si ratios, pore sizes, and NaCl concentrations. Molecular dynamics simulations were used to calculate the self-diffusion profiles of

and

ions. Results indicate that pore size strongly affects diffusivity and adsorption through confinement and electrical double layer effects. The solid surface influences ionic mobility up to approximately 1.2 nm. The Ca/Si ratio has minimal impact on the diffusion profiles of non-adsorbed ions, but its rise enhances

mobility near the surface and increases chloride binding capacity, consistent with prior studies.

水合硅酸钙（C-S-H）凝胶是一种具有复杂无序结构的无定形材料，这使得对其原子尺度性质的理解变得复杂。虽然许多研究已经研究了C-S-H孔中的离子扩散，但钠离子（）和氯离子（）的行为，特别是与Ca/Si比的关系，还没有得到很好的理解。在本研究中，建立了不同Ca/Si比、孔径和NaCl浓度下的C-S-H原子模型。采用分子动力学模拟方法计算了离子的自扩散曲线。结果表明，孔隙大小通过约束和电双层效应对扩散率和吸附率产生强烈影响。固体表面对离子迁移率的影响可达约1.2 nm。Ca/Si比对非吸附离子的扩散曲线影响最小，但它的上升增强了表面附近的迁移率，增加了氯离子的结合能力，这与先前的研究一致。

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引用次数: 0

Exploring the hydration potential and kinetics of Na-Ye'elimite and Ti-Ferrite solid solutions 探讨Na-Ye' limit和Ti-Ferrite固溶体的水化势和动力学

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2025-09-30 DOI: 10.1016/j.cemconres.2025.108046

Rahul Roy , Tobias Hertel , Christiane Rößler , Yiannis Pontikes

The addition of Bauxite residue in the raw mix introduces Na⁺ and Ti⁴⁺ into the crystalline phases of calcium-sulfoaluminate (CSA) clinkers. To mimic such a system, Na-Fe-ye'elimite (C₃.₉N₀.₁A₂.₈F₀.₂Ŝ) and Ti-ferrite (C₂F₀.₇₆A₀.₂₄T₀.₁) were synthesized at 1285 °C, 2 h, and 1320 °C, 3 h, respectively. Quantitative X-ray diffraction (QXRD) revealed solid solutions with minor Ca-aluminates phases, whereas electron backscattered diffraction-energy dispersive spectroscopy (EBSD-EDS) could distinguish Na-rich orthorhombic and Fe-rich cubic ye'elimite polymorphs. Isothermal calorimetry showed the Na-Fe-ye'elimite phase drives early heat evolution, whereas higher ferrite and gypsum (M > 0) prolong induction and attenuate the main hydration peak. In ferrite-free mixes, the cubic-ye'elimite polymorph dissolves fastest, but when ferrite exceeds 33 wt%, its Fe³⁺ release accelerates orthorhombic-ye'elimite dissolution, as confirmed by pore-solution analysis. After 28d, Na-Fe-ye'elimite is fully consumed at M (sulfate to ye'elimite molar ratio) ≥ 2 for ye'elimite-ferrite mixes, while ferrite remains partly inert, possibly from Ca²⁺/SO₄²⁻ adsorb onto its FeAl surface. Limiting ferrite to ≤33 wt% is recommended to achieve more densification of the microstructure for better performance.

在原料混合物中加入铝土矿渣将Na+和Ti4+引入到硫铝酸钙熟料的结晶相中。为了模拟这样的体系，Na-Fe-ye'elimite （C₃.₉N₀.₁a₂.₈F₀.₂Ŝ）和Ti-ferrite （C₂F₀.₇₆a₀.₂₄T₀.₁）分别在1285°C 2 h和1320°C 3 h下合成。定量x射线衍射（QXRD）显示固溶体中含有少量的钙铝酸盐相，而电子背散射衍射-能谱（EBSD-EDS）可以区分出富na的正交晶型和富fe的立方晶型。等温量热分析表明，Na-Fe-ye极限相推动了早期的热演化，而较高的铁素体和石膏（M > 0）延长了诱导过程，减弱了主水化峰。在不含铁素体的混合物中，立方晶型溶解最快，但当铁素体超过33%时，其Fe3+的释放加速了正交晶型的溶解，这一点得到了孔溶分析的证实。28d后，钠铁铁铁铁氧体混合物在M（硫酸盐与铁铁的摩尔比）≥2时被完全消耗，而铁氧体则保持部分惰性，可能是由于Ca2+/SO₄2 -吸附在FeAl表面。建议将铁素体限制在≤33 wt%，以实现更致密的组织，从而获得更好的性能。

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引用次数: 0