JOURNAL OF THE AMERICAN CERAMIC SOCIETY
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2025
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IF 3.8
Shuo Yan,Yuhong Chen,Ziqiang Yin,Binwei Huang,Quanxing Ren,Tihao Cao,Xuxin Ping,Ruibin Liu,Zhengren Huang,Qing Huang,Yinsheng Li
SiC ceramics were fabricated by spark plasma sintering of β-SiC powder with various rare-earth (RE = La, Gd, Yb, Sc) oxides and magnesia additives. The phase compositions, microstructures, lattice oxygen contents, and thermal conductivities were systematically investigated. A decrease in the cationic radius of rare-earth element resulted in an increased cationic field strength. This enhanced attraction to oxygen anion led to higher viscosity and improved high-temperature stability of the intergranular RE-Mg-Si-O liquid phase. After sintering at 1850°C, influenced by liquid-phase viscosity, the degree of β→α phase transformation in SiC and the grain size decreased with decreasing cationic radius of rare-earth element. After sintering at 2050°C, the liquid-phase viscosity significantly decreased, but volatilization became pronounced. The extent of β→α phase transformation and the grain size were affected by both liquid-phase viscosity and volatility. Larger grain size and higher affinity of rare-earth cations for oxygen anions contributed to reduce lattice oxygen content. The thermal conductivities of the SiC ceramics ranged from 192 to 229 W/mK. Notably, the SiC ceramic with Yb 2 O 3 -MgO additives exhibited the largest grain size, the lowest lattice oxygen content, and the elimination of β/α heterophase boundaries, thereby achieving the highest thermal conductivity of 229 W/mK.
研究领域:
材料科学
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热传导工程
✓ 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
Jun-Wei Huang,Xiao-Feng Dong,Xiao-An Lv,Xiao-Na Ren,Chang-Chun Ge
The Si 3 N 4 ceramics with ternary ZrN–AlN–Re 2 O 3 (Re=Yb, Y, Nd, Ce, La) and ZrN–AlN system as sintering additives were prepared by hot-pressed sintering with vacuum environment at 1750°C-30min–30MPa. Subsequently, the effect of the ternary additives system with 2 wt% Re 2 O 3 on phase transformation, grain boundary phases, microstructure, and mechanical properties of the Si 3 N 4 ceramics were investigated firstly. All samples achieved the high β-Si 3 N 4 phases transformation (≥98.86%), while the grain boundary phases Re x Zr 1-x O (4-x)/2 and Yb 2 Si 2 O 7 were detected in the sintered Si 3 N 4 ceramics with Re 2 O 3 additives. Additionally, compared with Si 3 N 4 ceramic not contain Re 2 O 3 additives, the Si 3 N 4 ceramics added Re 2 O 3 additives presented the textured microstructure with more elongated rodlike β-Si 3 N 4 grains based on the XRD and SEM results. Consequently, the sample S-Ce with added CeO 2 additive shows the highest relative density of 99.85% and optimal fracture toughness of 8.75 ± 0.36 MPa m 1/2 . The sample S–Nd with added Nd 2 O 3 additive presented a highest bending strength of 1061.78 ± 41.76 MPa. Sample S–Yb with added Yb 2 O 3 additive presented the maximum Vickers hardness of 16.35 ± 0.07 GPa. The results of this study can provide a helpful reference for the preparation of high-performance Si 3 N 4 ceramics.
研究领域:
材料科学
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陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Jun-Min Zhang,Xiao-Wu Chen,Xiao You,Qing-Gang Li,Meng-Meng Wang,Xiang-Yu Zhang,Yan-Mei Kan,Yu-Dong Xue,Shao-Ming Dong
The effect of RE 2 O 3 (RE = La, Y, Er, Lu) on the oxidation behavior of RMI-SiC ceramics in air and wet oxygen atmospheres at 1400 °C were studied. The outward migration of RE 3+ cations reduces the oxidation resistance of SiC-RE ceramics in air, but improves the wet-oxidation resistance of SiC-RE ceramics due to the formation of denser RE 2 Si 2 O 7 layer. The outward migration rates of RE 3+ cations may be influenced jointly by the RE 3+ cation radius and the formation rate of RE 2 Si 2 O 7 . The higher mobility of Er 3+ and Y 3+ cations makes Y 2 O 3 and Er 2 O 3 promising modifier for enhancing the wet-oxidation resistance of RMI-SiC f /SiC composites, although the modified components need to be optimized and further analyzed in a more realistic service environment.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
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2016
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IF 2.758
Hao Li,Zonglian Huang,Lijin Cheng,Shu Kong,Shaojun Liu
Novel monoclinic Bi 2 O 3 -xRE 2 O 3 -yMoO 3 (RE=Pr, Nd, Sm, and Yb) based low temperature co-fired ceramics (LTCC) systems with high sintering density and low microwave dielectric loss are synthesized by conventional solid state reaction technique. The structure and dielectric properties of Bi 2 O 3 -xRE 2 O 3 -yMoO 3 ceramics are investigated. Dense BiNdMoO 6 ceramics sintered at 900 °C for 8 h in air have a low dielectric constant ε r =~7.5, a high quality factor Q × f =~ 24, 800 GHz at 7.0 GHz, and τ f =~−16 ppm/̊C. Especially, good chemical compatibility of BiNdMoO 6 with Ag electrodes is represented as well. In contrast, BiSmMoO 6 ceramics sintered at 1000 °C for 8 h show enhanced Q×f =~43, 700 GHz at 7.8 GHz with ε r = ~8.5 and τ f = ~−27 ppm/°C. Bi 2 O 3 -xRE 2 O 3 -yMoO 3 (RE=Pr, Nd, Sm, and Yb) based ceramics could be considered as promising microwave ceramics for LTCC applications.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）