CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Yangli Xu,Zeling Yang,Guoqin Huang,Chenxu Ren,Guangyao Han,Xiaopeng Jiang,Tingting Li,Congming Ke,Yong Zeng,Xipeng Xu
Al 2 O 3 ceramic have excellent chemical inertness, superior heat resistance, and excellent corrosion resistance, so they are considered ideal materials for manufacturing high-performance components such as thermal end devices in aerospace, heat dissipation panels in electronic communication, and exhaust filters in the automotive industry. Digital Light Processing (DLP) is a useful technology to fabricate complex Al 2 O 3 ceramic components. However, the size shrinkage effect of DLP-fabricated components need to be investigated deeply before its further application. In this work, we utilized DLP technology to fabricate Al 2 O 3 ceramic honeycomb structures and systematically investigated their microstructure, size shrinkage, and mechanical properties. Our findings revealed that the Al 2 O 3 ceramic grains exhibit flake-like structures with an average diameter of 1–2 μm, and the ceramic particles are tightly bonded. The shrinkage rates in the X and Y axes were 7.54 % and 7.42 %, respectively, while the Z-axis exhibited a more significant shrinkage of 13.04 %. This anisotropic shrinkage in different direction was attributed to accumulation of the interlayer bonding under gravity action during debinding and sintering process. The compressive stress-strain curve of the honeycomb structures demonstrated a typical brittle compressive behavior, including elastic, stress plateau, and brittle fracture stages. The honeycomb structures exhibited an elastic modulus of 54.49 ± 1.22 MPa and a compressive strength of 10.22 ± 0.42 MPa. The fracture analysis indicated that the fractures region of honeycomb structures initiated at the corners of the honeycomb structures, indicating their easy-broken compared to the walls. These findings provide valuable guidance for the high-precision and high-performance manufacturing of complex Al 2 O 3 ceramic components.
研究领域:
材料科学
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制造工程
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产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2024
·
IF 5.8
Guo Wei,Junzhao Yuan,Yufan Zhou,Ziyao Wu,Jia-Tao Miao,Ren Liu
Polyimides are high-performance organic polymers with excellent insulation, high-temperature resistance, and mechanical properties. However, their poor solubility makes it challenging to use them to prepare solvent-free high-performance photocurable polyimide inks with low dimensional shrinkage. In this study, photocurable comb polyamic acid resins were synthesized, and their solubility was examined based on density functional theory (DFT) calculations. Experiments showed that polyamic acid resins with specific topologies could be dissolved in photocurable monomers to prepare solvent-free photocured polyimide inks. A custom-made UV-assisted direct ink writing 3D printer was used to fabricate complex three-dimensional devices. Further heat treatment caused the polyamic acids to undergo dehydration and cyclization into rigid polyimide structures, and this process exhibited less than 6% dimensional shrinkage. The final material had a maximum storage modulus of 3.1 GPa (40 ℃) and a glass transition temperature of 204 ℃. The good comprehensive performance suggests great potential for aerospace applications.
研究领域:
材料科学
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高分子化学
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航空航天工程
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产品关联
DOI
高影响因子
Catalysts
·
2025
·Vol. 15
·期 9
·832
·
IF 4
Haipeng Zhang,Shuai Luo,Pinghui Lin,Xu Lin,Xianghui Liu,Jiaqi Qian,Chenghui Lin,Zixiang Cheng,Na Ai,San Ping Jiang,Kongfa Chen
The chromium-free oxide precursor strategy effectively avoids chromium volatilization and electrode contamination in metal-supported solid oxide fuel cells (MS-SOFCs), while enabling high-temperature co-sintering in air to simplify the fabrication process. However, the drastic microstructural coarsening, dimensional shrinkage, and thermal expansion mismatch with adjacent components of such substrates during high-temperature sintering, reduction, and thermal cycling collectively contribute to the interfacial instability and structural degradation of MS-SOFCs. Herein, we address these issues by incorporating a small amount of Gd0.1Ce0.9O1.95(GDC) to the NiO-Fe2O3(NFO) substrate. The incorporation of GDC significantly enhances the sintering compatibility and reduction stability of the MS-SOFCs, alleviating the stress-induced warping and distortion. Moreover, the GDC phase has a pinning effect to suppressing the coarsening of the substrates during high-temperature sintering and reduction processes, enhancing mechanical integrity and structural robustness of the single cell. With 15 wt% GDC incorporated into the NiFe substrate, the corresponding MS-SOFC with GDC electrolyte film achieves a peak power density of 0.56 W cm−2at 600 °C, along with markedly improved structural integrity and operational reliability. This work demonstrates a viable pathway for designing heterophase-engineered supports with matched thermomechanical properties, offering promising prospects for enhancing the durability of MS-SOFCs.
研究领域:
材料科学
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能源工程
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固体氧化物燃料电池
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陶瓷材料
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热机械设计
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产品关联
DOI
高影响因子
BIOMATERIALS
·
2021
·
IF 12.479
Mengcheng Ma,Yafang Chen,Mingda Zhao,Junhui Sui,Zhihao Guo,Yuedi Yang,Zhiyi Xu,Yong Sun,Yujiang Fan,Xingdong Zhang
Integrating these features of acid-activated positively charged surface and size contraction into single nanoparticle would be an effective strategy for enhancing cellular uptake, intratumoral penetration and accumulation. Here, hierarchical responsive micelle (HVDMs) was developed via RAFT reaction as multifunctional polymer-drug conjugate for maximizing penetration and therapeutic effect against MCF-7 tumor by combining positively charged surface with size contraction: surface zeta-potential reversal (−2 to +12 mV) by protonation of PHEME and size contraction (~81–~41 nm) by simultaneous hydrophobic/hydrophilic conversion (pH ≈ 6.7); the disintegration of hydrazone bond between hydrophobic PVB and DOX triggered drug release (pH ≈ 5.0). The in vitro structural stabilization, cellular uptake and anti-proliferative efficiency were significantly higher than other control groups (CVDMs and HSDMs) at pH 6.7. The markedly increased penetration depth, cellular internalization and anti-tumor efficiency were confirmed in 3D MCSs spheroids at pH 6.7, and the ex vivo DOX fluorescence images further verified obvious penetration and accumulation in internal region of solid tumor. The antitumor effect in vivo demonstrated that HVDMs accelerated tumor atrophy, induced intratumoral cells apoptosis and alleviated system toxicity.
研究领域:
纳米技术
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癌症治疗
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药学科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
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