MATERIALS AND STRUCTURES
·
2024
·Vol. 57
·期 6
·1-14
·
IF 3.4
Liu Qing,Li Yunjian,Wang Qiao,Wang Miaomiao,Li Zongjin,Geng Guoqing
The inherent brittleness of cement hydrates poses a major issue to the mechanical and durable performances of concrete. To conquer this issue, we constructed an organic–inorganic network within the cement matrix by utilizing the synergy of in situ polymerization of monomers and cement hydration, which significantly enhances its flexural strength and toughness while maintaining a comparable compressive strength with ordinary Portland cement (OPC). By tuning the proportions of acrylic acid (AA), methacrylic acid (MAA), and acrylamide (AM), the cement paste experienced an 86% increase in flexural strength with a similar compressive strength to OPC. The in situ formed organic–inorganic (polymer-cement) network provided both flexibility and stiffness, playing a pivotal role in the increased mechanical strength. Cement hydration was retarded with the incorporation of the AMA copolymer, which was supported by the offset of the maximum hydration temperature. In contrast, in situ polymerization of monomers proved more effective than directly adding polymer in improving the fluidity and mechanical strength. We hope this strategy provides a new way to increase the crack resistance of cementitious materials and thereby contributes to their overall durability.
研究领域:
土木工程
·
材料科学
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产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Fan Zhang,Mao chen,Hailong Wang,Gang Shao,Yongshun Qi,Chengliang Ma,Bingbing Fan,Xiaoxuan Pian,Rui Zhang,Hongxia Li,Yongqiang Chen
The h-BN/ZrO 2 composites with different 3Y–ZrO 2 content were prepared by spark plasma sintering at 1800 °C. The sintering behavior , bulk density, apparent porosity , thermal conductivity , thermal expansion coefficient , bending strength , thermal shock resistance , microstructure and phase were analyzed. The optimum specimens were used to test the resistance to corrosion of molten steel for 10, 20, 40, 80 min respectively. The results indicated that ZrO 2 could facilitate the sintering process of h-BN matrix under the action of spark plasma. Especially, for the composites with 30 wt% 3Y–ZrO 2 , the porosity could decrease to 1.1% and the flexural strength could exceed 150 MPa. The microstructure showed the h-BN grains and 3Y–ZrO 2 grains are closely combined. The XRD patterns indicated that the t-ZrO 2 diffraction peak gradually enhanced with the increase of density. With the increase of erosion time, the erosion rate increased significantly. After the surface of the specimen is eroded, the erosion resistance of the matrix would decrease significantly. This h-BN/ZrO 2 could be as side-dam used in the thin strip continuous casting process .
研究领域:
材料科学
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陶瓷工程
✓ 已验证
DOI
高影响因子
Journal of Sustainable Cement-Based Materials
·
2025
·
IF 4.2
Fengjuan Wang,Haotian Liu,Xiaozhu Wang,Jinyan Shi,Yang Xu,Jinyang Jiang
The incorporation of polymers in Portland cement-based materials demonstrates remarkable potential for increasing flexural strength and toughness, but faces a critical challenge of compressive strength significant reduction caused by inhomogeneous polymer distribution. To address this bottleneck, this study developed polyacrylamide-cement (PAMC) composite materials through an innovative in-situ polymerization strategy of acrylamide (AM) monomers. This study systematically investigationd the mechanical properties of PAMC with varying AM dosages (1–5%), revealing an optimal AM content achieving 89.6% enhancement in 7-d flexural strength while maintaining 91.7% retention of compressive strength. Multi-scale characterization combining FTIR spectroscopy, XRD analysis, and TG-DSC measurements elucidated the phase evolution and hydration modification mechanisms during PAMC formation. SEM observation and MIP analysis elucidated the dual mechanism involving both polymer network structure enhancement and pore structure refinement. This work establishes fundamental correlations between polymerization-controlled microstructure optimization and macroscopic performance enhancement, providing new insights for developing high-performance cement composites.
研究领域:
土木工程
·
材料科学
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产品关联
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2023
·
IF 7.4
Shuzhen Zheng,Hong Zhou,Shoufang Xu,Yinwen Li,Dengxue Ma,Jianfeng Ma,Qianping Ran
The flexural strength and compressive strength are the two most important parameters that characterize the mechanical properties of cement-based materials, but the two are usually mutually exclusive or negatively correlated. The flexural strength of cement-based materials cannot be effectively improved by a single nanomaterial without reducing their compressive properties. Therefore, compounding various micro–nano materials, fully utilizing their respective advantages, and developing composite materials with new properties and application characteristics are important techniques for enhancing the mechanical properties of cement-based materials. This study aimed to investigate the synergistic enhancement of the mechanical properties of concrete by using microcrystalline cellulose (MCC) and nano-silica (NS) composites. MCC and NS were mixed and modified to synthesize MCCNS materials, which were added to cement slurry for experiments. Results indicated that the flexural strength and compressive strength of the cement paste with MCCNS materials were significantly increased compared with those of the cement pastes without MCCNS or with only NS. The flexural strength of the cement paste with MCCNS-1 was increased by 47%, 20%, 6.3%, and 6.8% after curing for 1, 7, 28, and 56 days, respectively. Meanwhile, compressive strength was also increased by 14.4%, 6.3%, 6.8% and 6.5%, respectively. In addition, the reaction mechanism was speculated through a variety of test results. The addition of MCCNS material facilitated the formation of additional C-S-H, which also contributed to enhancing the mechanical properties of cement paste.
研究领域:
建筑材料学
·
材料科学与工程
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DOI
高影响因子
MATERIALS AND STRUCTURES
·
2022
·Vol. 55
·期 1
·1-15
·
IF 4.285
Wang Xiaonan,Feng Decheng,Zhong Jing,Shi Xianming
The investigations on reduced graphene oxide (rGO) or graphene as an additive for cement reinforcement is relatively limited. Previous studies either employed thick graphene nanoplates, obscuring the flexible nature of graphene, or involved toxic agents, hindering their practical applications. Interestingly, in spite of the importance of uniform dispersion, there is still no method for quick and effective evaluation of the dispersion quality of rGO in both water and pore solution. Here, we prepare high-quality rGO by green chemical reduction of graphene oxide, followed by thorough washing without drying. The dispersion quality of rGO was assessed by dynamic light scattering, transmission electron microscopy, as well as morphological characterization of rGO film prepared by filtration. Because of water depletion by cement hydration, rGO agglomeration in pore solution is inevitable even for 0.05 wt% rGO/cement nanocomposites. This work shows that the compressive and flexural strength of a cement paste at 28 days were enhanced by 16.5% and 20.9% by admixing 0.05 wt% rGO, corresponding to very high reinforcement efficiency of 330% and 418%, respectively. Interestingly, the extremely low concentration (0.01 wt%) of rGO resulted in a decrease of flexural strength of cement paste. This is probably attributable to the flexibility of rGO nanosheets, which allows rGO to conformally wrap cement particles and affect its hydrated microstructure. Therefore, a minor level of rGO agglomeration is likely beneficial to the effective reinforcement of cementitious material by rGO, and the effect of nanosheets encapsulating the reactive particle or its matrix should be considered.
研究领域:
材料科学
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土木工程
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产品关联
DOI
高影响因子
International Journal of Applied Ceramic Technology
·
2025
·Vol. 22
·期 6
·e70052
·
IF 2.3
Na Zhang,Min Niu,Lei Su,De Lu,Kang Peng,Hongjie Wang
Si 3 N 4 ceramics stand out as ideal materials for advanced electronic packaging substrates due to their high mechanical strength, high-temperature resilience, and minimal dielectric constant. Optimizing both the mechanical and thermal conductivity is essential for ensuring their reliable performance. In this study, a systematic investigation into the impact of both oxygen-containing sintering additives (Y 2 O 3 -MgF 2 and Y 2 O 3 -MgSiN 2 ) and oxygen-free sintering additives (YF 3 -MgF 2 and YF 3 -MgSiN 2 ) on the microstructure, flexural strength, and thermal conductivity of Si 3 N 4 ceramics has been performed. It demonstrates that the Si 3 N 4 ceramic sintered with the YF 3 -MgSiN 2 additive achieves a remarkable thermal conductivity of 111.63 W·m −1 ·K −1 and a flexural strength of 774.7 MPa, which is relatively rare among the reported Si 3 N 4 ceramics. These exceptional properties are attributed to the use of YF 3 -MgSiN 2 additive, which leads to a significant reduction in lattice oxygen content, along with a decrease in the liquid phase formation temperature, thereby promoting grain development. Furthermore, the decomposition of MgSiN 2 at high temperatures plays a key role in purifying the grain boundaries. This study provides a promising approach for developing high-performance Si 3 N 4 ceramics with excellent thermal conductivity and mechanical strength.
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产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·Vol. 50
·期 15
·26493-26502
·
IF 5.1
Lan Zhang,Meihui Xiao,Jiali Li,Lin Chen,Jun Sun,Jianjun Ding,Xiaoxiao Li,Yi Gong,Kang Zheng,Xian Zhang,Xingyou Tian
The Bi 2 O 3 –B 2 O 3 –SiO 2 –ZnO–Al 2 O 3 (BBSZA) glass/Al 2 O 3 composites are prepared by quenching and quenching-free methods and conducted a comparative analysis of their microstructures and properties. The results reveal that the BBSZA/Al 2 O 3 composite obtained by quenching free method has smaller pores and superior performance. Specifically, at a BBSZA content of 50 wt%, the composite exhibits a thermal conductivity of 5.352 W/m·K and a flexural strength of 193.54 MPa, which are 1.38 times and 2.08 times those obtained using the quenching method, respectively. XRD and TEM analyses , along with parallel experiments using other glasses, suggest that presintering crystallization may be the prerequisite for achieving denser composites via the quenching-free method. BBSZA glass reacts with Al 2 O 3 at the presintering process to generate a great amount of ZnAl 2 O 4 crystals, which enhances grain boundary energy and increases sintering density. This work provides insights into the low-cost and high-performance development of low temperature co-fired ceramics (LTCC).
研究领域:
材料科学
·
无机非金属材料
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陶瓷学
·
复合材料工程
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电子封装材料
✓ 已验证
DOI
高影响因子
Virtual and Physical Prototyping
·
2025
·
IF 8.8
Boran Wang,Yongkang Yang,Xin Li,Jiachen Liu,Xue Dong,Anran Guo
As the internal cooling structure of aero-engine hollow turbine blades becomes more complicated, the corresponding ceramic core structures have also become more complex. This has made the vat photopolymerization (VPP) 3D printing technology a key research direction in the field of ceramic core manufacturing. Therefore, after investigating the influence of varying solid loadings on the performance and forming accuracy of ceramic cores, this study further introduces the curing depth-to-overcuring width control factor () and systematically explores the multi-factor optimisation strategy of UV absorber (2,2'-[(3,3'-dichlorobiphenyl-4,4'-diyl)di(E)diazene-2,1-diyl]bis[N-(2-methylphenyl)-3-oxobutanamide], PY14) content and forming parameters on forming accuracy. The results show that when the solid loading of the ceramic slurry reaches 70 vol.%, the sintering shrinkage rate of the ceramic core is 2.91%, and the flexural strength is 14.24 MPa, while the increase in the over-curing width can be as high as 106.82%; when the addition amount of PY14 is 2.5 wt.‰ and the slice thickness is set at 100 μm, the fluctuation of reaches the minimum value, and the prepared ceramic core has high forming accuracy and excellent performance. The research results of this paper are helpful to promote the wide application of VPP 3D printing technology in the field of ceramic cores.
研究领域:
材料科学
·
先进制造
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陶瓷工程
·
增材制造
·
航空发动机部件
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Weijie Han,Jian Yang,Chaozheng Ding,Wentao Xu,Youfu Zhou,Maochun Hong
Two-step sintering (TSS) method was widely used to prepare fine grained ceramics with high density, smaller grain, and more uniform microstructure, which improved the mechanical properties of ceramics. AlON transparent ceramics with good mechanical properties were prepared successfully by TSS method. The TSS process includes steps at a high temperature T 1 and then at a low T 2 . The grain size of ceramics gradually increased with the increase of T 1 . When T 1 was between 1900 °C and 1930 °C, the relative densities of AlON ceramics exceeded 98 % with the grain size less than 20 μm. The effects of T 2 = 1800 °C for various holding time (12–16 h) were also investigated. The grains increased slightly with the increase of holding time. Compared with conventional pressureless sintering (CS), TSS was more beneficial to regulate grain size with better properties. The grain size decreased from 118 μm (CS) to 53.7 μm (TSS), resulting in good in-line transmittance (81.7 % at 1500 nm with 2 mm thickness). The hardness and the flexural strength via TSS is 17.36 GPa and 368 MPa, which is increased by 5 % and 20 % respectively. TSS paves a potential path to improve mechanical properties of AlON transparent ceramics.
研究领域:
材料科学
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陶瓷
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Dawei Guan,Xianwen Wang,Xiaoyan Chen,Yaozhong Zhang,He Li,Qingxiao Yu,Fei Li
Silica ceramic cores are widely used for forming the inner cavity in hollow turbine blade casting. While the employment of 3D printing brings complex shapes and high production efficiency of ceramic cores, the clear downside of poor properties hinders their practical applications in comparison with traditional ones. This work aims to improve the comprehensive performance of 3D-printed silica ceramic cores, where the proposed powder gradation design leads to silica ceramic cores with high porosity, low shrinkage, and excellent high-temperature flexural strength. DLP-based 3D printing was utilized for ceramic core fabrication here. The studies on the powder shape and size reveal the merits of spherical particles on the flow and irregular particles on the stationarity of ceramic slurry. The sintering process suggests that coarse powder provides sufficient porosity for the core, while medium and fine powder enhance the densification degree of the core. As a result, when the mass ratio of coarse, medium, and fine powders was 1:1:2 and sintered at 1200 ℃, the comprehensive performance of the ceramic core was significantly improved, with a high open porosity of 30 %, reduced shrinkage rate to 1.2 %, surface roughness Ra reduced to 1.25 μm, and the high-temperature flexural strength increased to 39 MPa. This study will provide theoretical guidance and data support for 3D-printed silica ceramic cores.
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2025
·
IF 8.3
Haodong Zeng,Wenkai Li,Zhiqi Zhu,Yunlong Wu,Xingchen Pan,Zhiyong Xie
Graphite composite bipolar plates (BPs) exhibit exceptional electrical conductivity, corrosion resistance, and manufacturability, making them prime candidates for meeting DOE mass production standards. This study develops enhanced composite BPs by creating continuous hydroxylated multi-walled carbon nanotube networks on graphite substrates via chemical vapor deposition (CVD), subsequently incorporating carboxylated polyetheretherketone resin. The composite BPs achieved optimal performance with a 15-min carboxylation treatment, exhibiting a through-plane electrical conductivity of 224.9 S/cm and a flexural strength of 57.4 MPa. Compared to samples without carboxylation or hydroxylated MWCNTs, the corrosion resistance also improved, with the lowest corrosion current density recorded at 0.63 μA/cm 2 . However, excessive carboxylation time led to resin accumulation, resulting in degradation of the BPs’ properties.
研究领域:
材料科学
·
能源材料
·
电化学
·
高分子复合材料
·
燃料电池技术
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2024
·Vol. 17
·期 20
·5126
·
IF 3.1
Ke-Ke Yu,Tai-Qi Zhao,Qi-Ling Luo,Yang Ping
Three-dimensional printed concrete (3DPC) is increasingly recognized in the construction industry for its high design flexibility and the elimination of conventional formwork. However, weak interlayer adhesion remains a significant challenge. The potential of recycled polyethylene terephthalate (PET) fibers for reinforcing 3DPC is being explored, driven by their environmental sustainability and economic advantages. However, there is an inadequate interfacial adhesion between these recycled fibers and the 3DPC matrix. This study investigated the use of dopamine modification to address this issue and enhance the interlayer adhesion of fiber-reinforced 3DPC. Recycled PET fibers were surface-modified using dopamine treatment, forming a polydopamine (PDA) film that improved surface roughness and hydrophilicity. Both unmodified and modified fibers were incorporated into 3DPC at various volume fractions (0.1%, 0.3%, 0.5%). The effects on interlayer adhesion strength, compressive strength, and flexural strength were systematically evaluated and compared. The results showed that the inclusion of 0.3 vol% dopamine-modified fibers resulted in a 22.5% increase in interlayer adhesion strength compared to the control group, and a 14.8% improvement over unmodified fibers at the same content. Additionally, the compressive strength and flexural strength of 3DPC with 0.3 vol% MPET fibers increased by 22.5% and 27.6%, respectively, compared to the control group. Microstructural analysis using SEM and XRD revealed that the dopamine modification significantly improved the interfacial adhesion between fibers and the concrete matrix, explaining the superior performance of modified fibers. This study demonstrates that recycled PET fibers modified with dopamine can effectively enhance the interlayer adhesion of 3DPC. The findings affirm that surface modification techniques can significantly elevate the utility of recycled PET fibers in 3DPC, contributing to the sustainable advancement of construction materials.
研究领域:
土木工程
·
材料科学
·
可持续建筑
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）