CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Zhixin Wang,Yaowu Wei,Huayun Sun,Junfeng Chen,Bingqiang Han
ZrC was synthesized using sol-gel-like methods and carbothermic reduction techniques, employing Zr(OPr n ) 4 and carbon black as raw materials and CaF 2 as catalyst. High-crystallinity ZrC were obtained after a 20-minute hold at 1550°C. The effects of CaF 2 content and heat treatment temperature on structural transformation of the precursor, phase evolution, microstructural evolution and elemental composition analysis, as well as to analyze the catalytic mechanism of CaF 2 were investigated. The results indicated that this method enables effective and uniform mixing of ZrO 2 and carbon black. Adding CaF 2 promoted the deoxygenation of ZrO 2 and ZrC x O 1-x to ZrC, reducing the initial formation temperature of ZrC to 1300°C. The carbothermal reaction was nearly complete at 1500°C, yielding a composition of ZrC 0.951 O 0.049 at 1600°C. Thermodynamic calculations showed that CaF 2 react with ZrO 2 to form an intermediate phase of ZrF 4 , altering the reaction mechanism and reducing the theoretical initial synthesis temperature of ZrC to 1000°C.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
·
IF 4.175
Hao Li,Cuiwei Li,Linghao Wu
Porous cordierite ceramics with a single phase, high porosity and high strength were in-situ prepared using periclase, alumina and silica powders as raw materials by foam-gelcasting technique firstly. The reaction mechanism of preparing process was investigated via TG-DTA, X-ray diffraction, scanning electron microscope and electron energy disperse spectroscopy. The results confirmed that Mg(OH) 2 was formed during the preparation of green body and cordierite was formed at 1325 °C through the intermediate phases of cristobalite and MgAl 2 O 4 spinel. Samples with different performance have been fabricated by changing experimental parameters. Through altering holding time, sintering temperature and solid content in a certain scale, high porosity (83.9–89.2%), low bulk density (0.28–0.42 g/cm 3 ) and high compressive strength (0.9–4.7 MPa) were obtained. The SEM images showed that the pore structure of the as-prepared material was multiscale, the cordierite grains were irregular and the grain size was below 5 μm. The method used in this paper shows great promise for preparing porous cordierite ceramics with single phase, high porosity and high strength.
研究领域:
材料科学
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陶瓷工程
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DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2024
·
IF 3.5
Yongqiang Chen,Mao Chen,Beibei Tang,Guoqi Liu,Hongxia Li,Hailong Wang,Bingbing Fan
A uniform, dense, and well-bonded mullite/Y 2 Si 2 O 7 /ZrO 2 (MYZ) composite barrier coating was synthesized using a spraying technique followed by a two-step sintering process. The microstructure, phase composition, and thermal shock resistance of the MYZ coating were systematically investigated. The sintering process comprised two stages. In the initial stage (25–1350°C), granular mullite grains transformed into columnar crystals with progressive growth. Concurrently, a eutectic composite of mullite and Y 2 Si 2 O 7 formed and dispersed within the grain boundaries, significantly enhancing the coating's density and adhesion. In the subsequent stage (∼1400°C), ZrO 2 reacted with the eutectic composite to produce yttria-stabilized zirconia (YSZ) in situ. The YSZ phase exhibited excellent interfacial compatibility with the substrate, markedly improving the coating's high-temperature stability. As a result, the coating achieved high hardness and a coefficient of thermal expansion matching that of the SiC substrate. Remarkably, the MYZ coating withstood 20 thermal cycles between 25°C and 1200°C without noticeable interfacial damage.
研究领域:
材料科学
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高温材料
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涂层技术
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DOI
高影响因子
JOURNAL OF IRON AND STEEL RESEARCH INTERNATIONAL
·
2023
·Vol. 30
·期 10
·2021-2030
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IF 2.5
Liu Hao,Zhu Yu-xuan,Wang Zhou-fu,Ma Yan,Wang Xi-tang
Magnesia castables have been widely used in metallurgical industries with the advantages of high refractoriness, non-polluting steel, and resistance to alkaline slag. Magnesia castables were prepared using strontium carbonate (SrCO 3 ) as additive to enhance slag resistance and mechanical properties, and the influence of SrCO 3 on the evolution of phases, microstructure and properties of magnesia castables sintered at different temperatures was clarified. The results show that, with the introduction of SrCO 3 (lower than 3 wt.%), elastic modulus, mechanical strength, thermal shock resistance and densification of magnesia castables were significantly enhanced owing to the formation of needle-like Ca 0.9 Sr 0.1 MgSi 2 O 6 phase and liquid phase when sintering at high temperatures, and the introduced SrCO 3 presented minor effects on the mechanical properties of castables for its highly structural stability below 1100 °C. During the slag corrosion process, SrCO 3 and SiO 2 in castables reacted with Al 3+ in molten slag to form SrAl 2 SiO 8 phase, resulting in the increased slag viscosity and suppressed continuing penetration.
研究领域:
材料科学
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冶金工程
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DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2025
·
IF 8
Na Zhang,Anxin Liu,Ling Chen,Xiangyu Xue,Hongfa Yu,Mingfang Ba
This study systematically investigated the hydration process and phase evolution of MgO-MgSO₄-H₂O (M-M-H) systems with and without chemical additive at different hydration stages using X-ray diffraction (XRD), electrochemical impedance spectroscopy (EIS), hydration heat measurement, and microstructural characterization. The results demonstrate that the formation of magnesium oxysulfate cement (MOSc) product phases is intrinsically governed by Mg²⁺ concentration in the liquid phase, which is co-regulated by both raw material molar ratios and phase regions. At low Mg²⁺ concentrations, the primary hydration products in chemical additive-free MOSc are 3Mg(OH)₂·MgSO₄·8H₂O (3–1–8 phase) and Mg(OH)₂. When Mg²⁺ concentration reaches a critical threshold, 5Mg(OH)₂·MgSO₄·7H₂O (5–1–7 phase) additionally forms in the system. Chemical additive significantly alter the hydration process by enhancing Mg²⁺ concentration and promoting MgO particle participation, ultimately shifting the dominant product phases to 5–1–7 and Mg(OH)₂. These findings provide deeper mechanistic understanding of hydration reactions in M-M-H systems and offer important guidelines for research and applications of chemically modified MOSc.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
Materials
·
2023
·Vol. 16
·期 3
·1053
·
IF 3.4
Yanpei Dang,Tianhao Li,Yangzhong Zhao,Liantai Duan,Jianning Zhang,Ke Chen,Liu He,Qing Huang,Chuanzhuang Zhao,Yujie Song
Polyborosilazanes with controllable B/N ratio were synthesized using high-boron-contentm-carborane, dichloromethylsilane, and hexamethydisilazane. After high-temperature pyrolysis, Si–B–C–N quaternary ceramics with SiC and B4C as the main phases were obtained. The B/N ratio in the precursors corresponded to the change in the feeding ratio of carborane and dichloromethylsilane. The effects of boron content and B/N ratio on the ceramic precursors and microphase structure in Si–B–C–N quaternary ceramics were explored in detail through a series of analytical characterization methods. A high boron content results in a significant increase in the ceramic yield (up to 71 wt%) of polyborosilazanes, and at the same time, the B/N molar ratio was regulated from 28.4:1 to 1.62:1. The appearance of the B4C structure in the Si–B–C–N quaternary ceramics through the regulation of the B/N ratio, has rarely been reported.Keywords:polyborosilazane;SiBCN;carborane;polymer derived ceramics;B/N ratio;microphase evolution
研究领域:
材料科学
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化学工程
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陶瓷
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DOI
PubMed
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2023
·
IF 3.3
Shibin Wu,Keru Song,Jianwen Wang,Siyu Huang,Fengyue Shi,Guangdong Zhao
ZrB 2 –SiC ceramics were successfully prepared via sol–gel method using phenyltrichlorosilane, borane dimethyl sulfide , and zirconium tetrachloride in stoichiometric amounts as the raw materials. The macromolecular network structure formed after the sol–gel process was investigated via Fourier transform infrared (FT–IR) spectroscopy. The phase evolution of the ZrB 2 –SiC ceramics were analyzed by FT–IR spectroscopy, X–ray diffraction, and transmission electron microscopy , whereas morphological and elemental analyses were performed using scanning electron microscopy. In particular, the change in phase composition was monitored after the pyrolysis from 1400 to 1500 °C, and the heat treatment of BZ6 precursor at 1500 °C enabled one to produce the ZrB 2 –SiC ceramic with a homogeneous crystal phase distribution. Therefore, the controllable microstructure adjustment of the ceramic phase composition could be achieved and a new way was paved for the structural and functional applications of ultra–high–temperature ceramics (UHTCs) series.
研究领域:
材料科学
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无机化学
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DOI
高影响因子
ADVANCED POWDER TECHNOLOGY
·
2025
·
IF 4.2
Jiaqi Wen,Chenghong Liu,Lihua Gao,Zhijun He
An oxidation roasting technology has been reported as an effective technology for successfully synthesizing nickel manganese ferrite Ni x Mn 1-x Fe 2 O 4 (0 < x < 1) with a spinel crystal structure. The experimental results demonstrated the successful synthesis of nickel manganese ferrite Ni 0.5 Mn 0.5 Fe 2 O 4 samples with relatively high purities at an oxidation roasting temperature of 1200 °C for 2 h with a Ni:Mn:Fe molar ratio of 1:1:4. The synthesized samples exhibited a magnetization saturation (Ms) value of 53.71 emu/g, a coercivity (Hc) value of 34.88 Oe, and a remanent magnetization (Mr) of 3.64 emu/g. Additionally, these samples had a total pore volume of 0.071 cm 3 /g, a Specific Surface Area (SSA) of 24.13 cm 2 /g, and an Average Particle Size (APS) of 12.32 nm. It was concluded that the synthesis route of Ni x Mn 1-x Fe 2 O 4 could be theoretically summarized into two routes. One route involves the simultaneous substitution of divalent iron (Fe 2+ ) and trivalent iron (Fe 3+ ) in the spinel structure of (Fe)[Fe] 2 O 4 by divalent manganese ions (Mn 2+ ) and trivalent nickel ions (Ni 3+ ), resulting in the formation of (Mn) x (Fe) 1-x [Ni] y [Fe] 2-y O 4 with a spinel crystal structure. In this structure, the Ni 3+ ions preferentially occupy the octahedral sites, whereas the Mn 2+ ions predominantly reside in the tetrahedral sites of the nickel manganese ferrites (Mn) x (Fe) 1-x [Ni] y [Fe] 2-y O 4 . Furthermore, the mixed spinel crystal structure of (Ni) y (Fe) 1-y [Mn] x [Fe] 2-x O 4 could be transformed into nickel manganese ferrite (Mn) x (Fe) 1-x [Ni] y [Fe] 2-y O 4 under the influence of a higher oxidization roasting temperature. Nickel manganese ferrite Ni x Mn 1-x Fe 2 O 4 (0 < x < 1) with normal and inverse spinel structures inevitably coexists and co-transformed in the synthesis process of Ni x Mn 1-x Fe 2 O 4 by oxidation roasting technology.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2025
·
IF 3.8
Jianning Zhang,Yanpei Dang,Tianhao Li,Yangzhong Zhao,Liantai Duan,Ke Chen,Xiao Zhang,Hengli Duan,Wensheng Yan,Sihua Feng,Gang Shao,Zhaoju Yu,Qing Huang,Yujie Song
Silicon boron carbonitride (SiBCN) ceramics have garnered significant attention due to their exceptional high-temperature stability, resistance to creep, and favorable electrical properties. However, the ceramicization mechanism of covalently bonded boron atoms in polyborosilazane (PBSN), which is crucial in determining the structural and crystalline phase evolution of silicon boron carbonitride (SiBCN) ceramics through the polymer-to-ceramic process, still needs further clarification for the design of advanced ceramics. Therefore, PBSN precursors constructed with B–C bonds were systematically investigated in the polymer-to-ceramic conversion process. B–C bonds were transformed into B-N bonds between 300°C and 600°C, ultimately resulting in the formation of h-BN at high temperatures. Meanwhile, higher levels (8.11–14.12%) of B facilitated the formation of SiC at equivalent temperatures but hindered the formation of Si 3 N 4 crystal nuclei. That is due to the formation of B–N and NB 3 units, which inhibited the formation of Si–N bonds and SiN 4 units, thereby interfering with the nucleation process of Si 3 N 4 and facilitating the crystallization of SiC. This study offers valuable insights for regulating the microphase evolution and properties of PDC nanocomposites.
研究领域:
材料科学
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陶瓷材料
·
聚合物衍生陶瓷
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固态化学
·
高温材料
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Dongping Yin,Qiuyu Zheng,Qiang Tian,Xiaofeng Zhao,Lian Bian,Weipeng Wang,Yuancheng Teng,Rui Ma,Rajeev Ahuja,Wei Luo,Zhengjun Zhang
Extraction of 90 Sr from groundwaters is of great significance in energy and ecological environment. Phosphate minerals have been proposed as a suitable matrix for the in-situ remediation of radionuclides from groundwaters by encouraging co-precipitation. However, the understanding of how Sr 2+ precipitate into phosphate minerals affected by grain growth has not been fully resolved. In this work, the precipitation reaction of Sr 5 (PO 4 ) 3 OH and SrHPO 4 were studied based on experiments and PHREEQC simulation. Some specific issues such as the precipitation reaction kinetics and the phase evolution during grain growth were discussed in detail, along with investigating the chemical stability of obtained precipitations before and after calcination . The results show that pH appears to be a prevailing factor with a recommended pH = 8 ∼ 11 to obtain the stability domain of Sr 5 (PO 4 ) 3 OH and SrHPO 4 to remove Sr 2+ with a removal rate over 98 %. Interestingly, SrHPO 4 is more likely to preferentially nucleate at pH = 8 solution compared to Sr 5 (PO 4 ) 3 OH, and the poorly crystalline SrHPO 4 tends to disappear over time. TEM and SAXS results show the plate-like nanoparticles of SrHPO 4 are wrapped into the rod-like particles of Sr 5 (PO 4 ) 3 OH during the grain growth, and the inner SrHPO 4 can react with Sr 5 (PO 4 ) 3 OH to form Sr 3 (PO 4 ) 2 at temperature over 600 ℃. This observation is inconsistent with the previous grain growth result of poorly crystalline SrHPO 4 , where it is believed to recrystallize into more stable Sr 5 (PO 4 ) 3 OH crystals over time. Moreover, the Sr-O binding energy plays an important role in controlling the degradation of Sr 5 (PO 4 ) 3 OH, Sr 3 (PO 4 ) 2 , SrHPO 4 and β -Sr 2 P 2 O 7 .
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高影响因子
Journal of Advanced Ceramics
·
2020
·Vol. 9
·期 3
·320-328
·
IF 2.889
Yu Zhaoju,Yang Yujing,Mao Kangwei,Feng Yao,Wen Qingbo,Riedel Ralf
A novel single-source-precursor for SiC-TaC-C nanocomposites was successfully synthesized by the chemical reaction between a polycarbosilane (allylhydridopolycarbosilane, AHPCS) and tantalum(V) chloride (TaCl 5 ), which was confirmed by Fourier transform infrared spectra (FTIR) measurement. After pyrolysis of the resultant single-source-precursors at 900 °C, amorphous ceramic powders were obtained. The 900 °C ceramics were annealed at different temperatures in the range of 1200–1600 °C to gain SiC-TaC-C nanocomposites. The phase evolution of ceramic nanocomposites was investigated by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results indicate that the TaC starts to crystallize at lower temperature than the β-SiC. It is particularly worth pointing out that the unique core-shell structured TaC@C nanoparticles were in-situ formed and homogeneously distributed in the ceramic matrix after annealing at 1400 °C. Even at a high temperature of 1600 °C, the grain sizes of β-SiC and TaC are smaller than 30 nm, fulfilling the definition of nanocomposites. The present study related to SiC-TaC-C nanocomposites paves a new road for enriching ultra-high temperature ceramic family suitable for structural/functional applications in harsh environment.
研究领域:
材料科学
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纳米技术
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DOI
高影响因子
Journal of Cleaner Production
·
2020
·
IF 7.246
Ya-Jun Wang,Ya-Nan Zeng,Jun-Guo Li,Yu-Zhu Zhang,Ya-Jing Zhang,Qing-Zhong Zhao
This study focuses on evaluating the carbonation potential of argon oxygen decarburization (AOD) slag and analyzing influence mechanism of carbonation on chromium leachability . Static thin-film accelerated carbonation and sequential leaching tests were carried out. Results show that the liquid to solid (L/S) ratio was the most influencing factor for AOD slag’s carbonation, and the maximum carbonation ratio of AOD slag was 50–52% (L/S = 0.4 mL/g, P CO2 = 7.5 bar, and t > 6 h). Dicalcium silicate’s carbonation resulted in the generation of amorphous calcium carbonate , crystalline calcite and silica gel . AOD slag’s smooth surface could be eroded by these products gradually with carbonation furthered. The mineral phase evolution clearly influenced the mineral phase hydrolysis and physical encapsulation, and thus affected the hydrolysis behavior of the primary phase and the generation behavior of the secondary phase in the carbonated slags. Chromium leachability (20 days) declined to its lowest value (1.7 mg/kg) as the carbonation ratio growing to 23% and then increased to its highest value (7.9 mg/kg) with the carbonation ratio increasing to 52%. Chromium leachability varies with the carbonation ratio. The optimal carbonation ratio that resulting in minimum chromium leaching risk must be taken full in mind before using AOD slag in carbonation-related production activities.
研究领域:
材料科学
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环境工程
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化学工程
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DOI
高影响因子
危险品化学品经营许可证（带存储）