CERAMICS INTERNATIONAL
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2023
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IF 5.2
Hongmei Chen,Shu Yu,Yunping Li
SiOC and SiCaMgOC coatings were prepared by sol–gel method from precursors of hydrosilane and the mixture of hydrosilane, calcium acetylacetonate (Ca(acac) 2 ) and magnesium acetylacetonate (Mg(acac) 2 ), respectively. Fourier transform infra-red (FTIR) and X-ray photoelectron spectroscopy (XPS) analysis on the coatings revealed that Ca 2+ and Mg 2+ ions can be successfully doped into SiOC coating after aging and annealing in the SiCaMgOC coating. The cytotoxicity and bioactivity of three samples have been detected by MTT assay, cell adhesion and simulated boy fluid (SBF) immersion test. The results suggested that SiCaMgOC coating induced more apatite than that of C/C and SiOC in the comparable soaking process. SiCaMgOC coating demonstrated better biological activity and cellular adherence for its higher surface roughness and ion exchange reaction between Ca 2+ and Mg 2+ ions and protons (H + /H 3 O + ) in the SBF solution.
研究领域:
材料科学与工程
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生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2024
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IF 6.3
Yun-Yang Li,Hao-Jie Yan,Ruo-Zhan Yin,Qing-Qing Sun,Lian-Kui Wu,Fa-He Cao
In this work, SiOC coatings incorporated with Ni nanoparticles were fabricated on γ-TiAl alloy by dip-coating. The microstructure and high temperature oxidation behavior of the SiOC-Ni coatings with different Ni contents were investigated. Results showed that the incorporation of Ni nanoparticles improved the oxidation resistance of the SiOC coating at 850 ℃. During thermal exposure to air, the incorporated Ni particles would react with both oxygen and the SiOC coating, forming NiO and Ni 2 Si, respectively, therefore changing the structure of the SiOC coating. The generation of NiO and Ni 2 Si is beneficial in reducing the oxygen partial pressure at the coating/substrate interface, thereby facilitating the formation of a protective aluminum oxide layer.
研究领域:
材料科学
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表面工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2024
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IF 5.8
Qi You,Zhongyang Wu,Yongjun Li,Ya Zhong,Sisi Shang,Man Yuan,Yichen Ou,Huanhuan Xu,Sheng Cui
Mullite aerogel is considered a promising candidate for thermal protection. However, structural collapse and poor temperature resistance limit its application at high temperature. Herein, amorphous SiOC-coated mullite aerogels (MAs) were prepared by high-temperature calcination, using Al 2 O 3 nanorods and SiO 2 particles as precursor units. The one-dimensional submicron skeleton prevents weak pearl chain connections and high surface energy, while the nanoscale amorphous SiOC layer protects the encapsulated mullite skeleton, ensuring a strong skeleton and pores at high temperatures. MAs exhibit a low thermal conductivity of 0.0375 W/(m·K) at room temperature, a robust compressive strength of 0.369 MPa, and good thermal stability: after 30 min of annealing at 1500 ℃, the minimal linear shrinkage of MAs was 0.72 %. Interestingly, the amorphous SiOC layer grew into nanowires under a butane flame, which reconstructed the network and impeded the heat flow. Thus, the novel MAs exhibit considerable thermal insulation advantages in harsh environments.
研究领域:
材料科学
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热防护技术
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
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2023
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IF 5.2
Junjie Yan,Xiumei Wu,Qidong Liu,Yunping Li,Shu Yu
Silicon oxycarbide (SiOC) coatings were prepared through isothermal chemical vapor co-deposition by using two precursors of hexamethyldisilane (HMDS) and tetraethyl orthosilicate (TEOS). The microstructure, composition and the protectiveness on C/C composite against oxidation of the coatings prepared at temperatures ranging from 1423 K to 1563 K and pressures ranging from 500 Pa to 1200 Pa were investigated, respectively. After oxidation, cracks and defects were formed in the coatings of all conditions due to the volume shrinkage of amorphous SiO 2 crystallization and the mismatch of thermal expansion coefficient (CTE) between SiOC coatings and substrate. The most oxidation-resistant SiOC coating was obtained at 1563 K and 500 Pa, which exhibited the lowest weight loss rate of 4.87 % after 12 h of oxidation at 1673 K in air condition.
研究领域:
材料科学
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表面工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
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2024
·
IF 5.1
Wei Gao,Yongzheng Zhang,Yanli Wang,Liang Zhan
The carbon/phenolic composites are extensively considered as an efficient ablative thermal protection material, but inferior oxidation-ablation resistance has limited their further application. In this work, a multiscale ZrO 2 -SiOC coated carbon/phenolic composite (NCF/ZSAx-PA) was fabricated through a dual-stage construction strategy. The as-prepared composites exhibited a low density (0.314–0.348 g/cm 3 ), low thermal conductivity (0.0605–0.0725 W/(m·k)) and promoted compressive strength (2.95/5.08 MPa in the Z/XY direction). Benefiting from the formation of a protective ZrO 2 -SiO 2 ceramic coating, the multiscale composites showed excellent anti-oxidation and ablation performance. The residual weight of NCF/ZSAx-PA was 19.41 % at 1000 °C while the unmodified carbon/phenolic composites were entirely burnt off under an air atmosphere. Besides, the NCF/ZSAx-PA exhibited low back temperature (53.6 °C), low linear ablation rate (0.0519 mm/s), and low mass loss rate (0.0100 g/s) under the 3.62 MW/m 2 oxyacetylene assessment. All the superior properties enabled the NCF/ZSAx-PA a prospective application on the thermal protection system.
研究领域:
材料科学
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航空航天工程
✓ 已验证
产品关联
DOI
高影响因子