CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Guanglin Nie,Yehua Li,Pengfei Sheng,Zhuo Tian,Wei Liu,Haidong Wu,Yiwang Bao,Shanghua Wu
To improve the thermal and mechanical properties of Al 2 O 3 /AlN composite ceramics, a novel heterogeneous precipitation coating (HPC) approach was introduced into the fabrication of Al 2 O 3 /AlN ceramics. For this approach, Al 2 O 3 and AlN powders were coated with a layer of amorphous Y 2 O 3 , with the coated Al 2 O 3 and AlN powders found to favor the formation of an interconnected YAG second phase along the grain boundaries. The interconnected YAG phase was designed to act as a diffusion barrier layer to minimize the detrimental interdiffusion between Al 2 O 3 and AlN particles. Compared with samples prepared by a conventional ball-milling method, the HPC Al 2 O 3 /AlN composites exhibited less AlON formation, a higher relative density, a smaller grain size and a more homogeneous microstructure. The thermal conductivity , bending strength , fracture toughness and Weibull modulus of the HPC Al 2 O 3 /AlN composite ceramics were found to reach 34.21 ± 0.34 W m −1 K −1 , 475.61 ± 21.56 MPa, 5.53 ± 0.29 MPa m 1/2 and 25.61, respectively, which are much higher than those for the Al 2 O 3 and Al 2 O 3 /AlN samples prepared by the conventional ball-milling method. These results suggest that HPC is a more effective technique for preparing Al 2 O 3 /AlN composites with enhanced thermal and mechanical properties, and is probably applicable to other composite material systems as well.
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
·
2024
·
IF 5.1
Jiaqi Wang,Tongtong Gao,Huiling Zheng,Shuanglong Chen,Xuejiao Wang,Qiushi Wang
Rare-earth (RE) doped aluminum nitride (AlN) holds great promise for integrated optoelectronic devices. Here, the Ho and Yb co-doped AlN (AlN:Ho 3+ /Yb 3+ ) submicron towers were prepared by a direct nitridation route. XRD, Raman, XPS and EDS studies showed successful doping of Ho and Yb ions into AlN. SEM images show that the submicron towers have an interesting layered structure by layer-by-layer stacking of hexagonal AlN nanosheets. Under excitation at 980 nm, AlN:Ho 3+ /Yb 3+ submicron towers exhibit up-conversion (UC) luminescence at 540, 550, 659, and 762 nm, which are due to Ho 3+ /Yb 3+ system from 5 F 4 , 5 S 2 → 5 I 8 , 5 F 5 → 5 I 8 , and 5 F 4 , 5 S 2 → 5 I 7 respectively. Based on the intensity ratio and decay lifetime of UC luminescence, the optical temperature sensing characteristics are investigated from 298 K to 548 K. The maximum relative sensitivities associated with the intensity ratio of I 540, 550 and I 659 and decay lifetime of 659 nm are as high as 2.73% K −1 and 0.43% K −1 , respectively. This work broadens the optoelectronic properties of RE doped AlN.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
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
Journal of Advanced Ceramics
·
2022
·Vol. 11
·期 10
·1530-1541
·
IF 11.534
Zhang Chang,Hu Xiangchen,Nie Zhiwei,Wu Cong,Zheng Nan,Chen Shaojie,Yang Yihang,Wei Ran,Yu Jiameng,Yang Nan,Yu Yi,Liu Wei
Garnet-type oxide is one of the most promising solid-state electrolytes (SSEs) for solid-state lithium-metal batteries (SSLMBs). However, the Li dendrite formation in garnet oxides obstructs the further development of the SSLMBs seriously. Here, we report a high-performance garnet oxide by using AlN as a sintering additive and Li as an anode interface layer. AlN with high thermal conductivity can promote the sintering activity of the garnet oxides, resulting in larger particle size and higher relative density. Moreover, Li 3 N with high ionic conductivity formed at grain boundaries and interface can also improve Li-ion transport kinetics. As a result, the garnet oxide electrolytes with AlN show enhanced thermal conductivity, improved ionic conductivity, reduced electronic conductivity, and increased critical current density (CCD), compared with the counterpart using Al 2 O 3 sintering aid. In addition, Li symmetric cells and Li∣LiFePO 4 (Li∣LFP) half cells using the garnet electrolyte with the AlN additive exhibit good electrochemical performances. This work provides a simple and effective strategy for high-performance SSEs.
研究领域:
材料科学
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电化学
·
能量存储
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Mingyong Jia,Qianshun Cui,Yueqi Wu,Chengquan Shen,Qiang Shen,Fei Chen
Given the insufficient wettability and compatibility between ceramic and metal, heterogeneous grain boundaries in particular composites consistently represent the primary failure sites related to both mechanical loading and chemical corrosion. To solve as above–mentioned problem and improve the interfacial bonding of ceramic/metal composites, we performed a novel strategy to modify the grain boundaries of AlN/Mo composites via Ni nanoparticles , which was produced via rotary chemical vapor deposition . Without sacrificing ductility, a substantial 46.1 % increase in bending strength was successful attained arises from the combined influence of grain boundary density and diffusion depth, interfacial structure and electronic properties. In view of the limitations of the traditional blending methods, this study made full use of random nucleation characteristics during the oxidation/reduction process in RCVD to form uniform nanoparticle coating on the surface of AlN powder, thereby avoiding potential risks to AlN/Mo composites, such as brittle intermetallic compounds , localized performance variations.
研究领域:
材料科学
·
纳米技术
✓ 已验证
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2023
·
IF 4.9
Qianxiong Wen,Cong Zhao,Meilin Fu,Yusai Xu,Xiangjia Sun,Jiaying Zheng,Yanrong Liang,Weidong Xiang,Xiaojuan Liang,Zhaoping Chen
Phosphor-in-glass (PiG) has been prepared into various types of phosphor films owing to its simplicity process, exceptional color purity, and convenient color adjustability. Nevertheless, existing reflective PiGs films have encountered limitations in terms of stability and feasibility as reliable color converters, mainly attributed to issues related to thermal deposition and insufficient optical efficiency. Herein, we propose to use AlN substrate with superior thermal conductivity to coat the TiO 2 layer to obtain TiO 2 –AlN (TA), which enhances the reflectivity of blue light to facilitate the light conversion process. By incorporating highly thermally stable LuAG:Ce-PiGs on a TA substrate, the LuAG:Ce-PiTA converter exhibits a luminous flux of 1102 lm@6.4 W, and maintains a relative intensity of 94.6% at 473 K benefiting from the high thermal conductivity of 34.1 W/(m·K). The addition of CASN 3 :Eu to the color converter 50 L&10C-PiTA enables an impressive CRI of 90.7. Relative luminescence intensities of LuAG:Ce-PiTA and 50 L&10C-PiTA only decrease by 5.35% and 3.28%, respectively, in the 24 h illumination aging decay test of the reflective laser module. The results confirm the suitability of the optimally designed TA substrate for LuAG:Ce color converter applications in high-power reflective laser illumination.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Ya-Ru Wu,Jun-Hong He,Li-Jin Cheng,Jia-Min Wu,Yu-Sheng Shi
Porous Si 3 N 4 ceramics are widely used in the aerospace field due to its lightweight, high-strength, and high wave transmission. Traditional manufacturing methods are difficult to fabricate complex structural and functional ceramic parts. In this paper, selective laser sintering (SLS) technology was applied to prepare porous Si 3 N 4 ceramics using AlN as an inorganic binder. And the effects of AlN content on the properties of the obtained ceramic samples were explored. As the AlN content increased, nano-Al 2 O 3 and nano-SiO 2 formed the eutectic liquid phase, enhancing the sintering densification and phase transformation of Si 3 N 4 poly-hollow microspheres (PHMs). The island-like partial densification structures in Si 3 N 4 green bodies increased. During the high-temperature sintering, the eutectic liquid phase partially transformed into the mullite phase or reacted with AlN and Si 3 N 4 to form the Sialon phase. With the increase of AlN content, the fracture mode of Si 3 N 4 ceramics changed from fracturing along PHMs to fracturing across PHMs. The bonding depth between PHMs increased and the connection between the grains was tighter, so the Si 3 N 4 ceramics became denser. With the increase of AlN addition, the total porosity of the porous Si 3 N 4 ceramics tended to decrease and the flexural strength gradually increased. When AlN content was 20 wt%, the total porosity and the flexural strength were 33.6% and 23.9 MPa, respectively. The addition of AlN inorganic binder was carried out to develop a novel way to prepare high-performance porous Si 3 N 4 ceramics by SLS.
研究领域:
材料科学
·
航空航天工程
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2023
·Vol. 11
·期 20
·10727-10737
·
IF 11.9
Jiabin Hu,Zhilei Wei,Bangzhi Ge,Lei Zhao,Kang Peng,Zhongqi Shi
Phase-change materials (PCMs) for efficient thermal energy harvesting have promising prospects for thermal energy storage and thermal management. However, the low intrinsic thermal conductivity (TC) of PCMs is a long-standing drawback due to a lack of a thermally conductive network inside them. Herein, a cost-effective route for preparing thermal-conductive phase-change composites by freeze-casting and combustion synthesis to obtain micro-honeycomb aluminum nitride (MH-AlN) reinforcements followed by the impregnation with liquid stearic acid (SA) was presented. The as-prepared MH-AlN/SA composite at 44.46 vol% AlN loading exhibited a high TC of 13.95 W m−1 K−1 parallel to the pore channels, up to 53.49-fold higher compared with that of pure SA. The contact thermal resistance between AlN particles can be greatly lowered via constructing a three-dimensional MH-AlN network inside the SA matrix. Additionally, a typical solar thermoelectric generator was devised and photothermal-electric energy transformation was successfully realized. Real-time recorded maximum output voltage and current were 409.0 mV and 110.8 mA, respectively. The enhancement of the heat transfer gives MH-AlN/SA phase-change composites more application prospects in industrial waste heat utilization and effective solar energy harvesting.
研究领域:
材料科学
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热能存储
·
太阳能转换
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2018
·
IF 3.794
Jia-Qi Zheng,Jian Chen,Xue-Jian Liu,Zheng-Ren Huang,Jun-Jun Chen
Highly conductive SiC-MoSi 2 -AlN composites were fabricated by β-SiC, AlN and MoSi 2 powders with Y 2 O 3 additive via pressureless sintering. The effect of MoSi 2 content on the microstructure, mechanical and electrical properties of SiC-MoSi 2 -AlN composites was systematically investigated. A finer microstructure was obtained and electrical conductivity was enhanced with increasing MoSi 2 content. The impedance spectroscopy and potential-current measurements were implemented to figure out the electrical conduction mechanism. The introduction of MoSi 2 effectively reduced the Schottky barrier height at the grain boundary, and subsequently the U-I curves changed from nonlinear to linear electrical characteristics . The notable decrease in electrical resistivity was owing to the breakdown of grain boundaries and the formation of percolation paths. The percolation threshold was in the range of 0–5.44 vol% MoSi 2 , much lower than the reference value. The composites with 10 wt% MoSi 2 exhibited an electrical resistivity of about 60 Ω cm, suitable for infrared source element applications.
研究领域:
材料科学
·
电气工程
·
陶瓷学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
·
2021
·
IF 5.584
Xianglei Liu,Haolei Wang,Qiao Xu,Qingyang Luo,Yanan Song,Yang Tian,Meng Chen,Yimin Xuan,Yi Jin,Yixuan Jia,Yongliang Li,Yulong Ding
Ceramics embedded phase change materials (PCMs) composites are promising candidates for high-temperature thermal energy storage due to good chemical stability and high thermal shock resistance. However, the energy storage rate is severely restricted by the low thermal conductivity of composites. Here, we successfully achieve high thermal conductivity and high energy density compatible thermal energy storage based on porous AlN-eutectic NaCl/LiNO 3 composites. Designed composites possess a high thermal conductivity ranging from 31.8 to 52.63 W/m-K benefiting from continuous thermal transport channels of densified AlN skeletons. Meanwhile, the phase change enthalpy reaches 140 to 186 kJ/kg since about up to 92% of pores are filled with PCMs. Further decorating AlN skeletons with TiN nanoparticles can significantly increase the solar absorptance from 70% to 90%, enabling proposed composites to be applicable for direct solar thermal energy storage as well. This work provides new routes to achieve high thermal conductivity and energy density compatible thermal energy storage via porous AlN ceramics-based phase change composites.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Jifan Yang,Yuxuan Yang,Fei Long,Xuan Li,Fei Sun,Chenhao Qian,Xinyu Yan,Tong Zhou,Lei Liu
AlN ceramic is the potential substrate for high-performance printed circuit board with the rapid development of electronic industry due to the superior thermal and electrical property, while its metallization still faces the issues of thermal stress and weak interface bonding with existing technology. Herein, a convenient design is proposed to achieve the Cu deposition on the surface of AlN substrate, the TiO 2 containing photocatalytic intermediate layer is prefabricated on AlN substrate with silica and titania mixed sol, and induces the autocatalytic deposition of electroless copper plating under ultraviolet irradiation. Compared with Cu deposition with Pd activation treatment, the bonding strength between Cu layer and AlN substrate is significantly enhanced with the intermediate layer, this is ascribed to the formed nano-porous microstructure of the sintered intermediate layer facilitating the penetration of plating bath, and the mechanical anchoring effect derived from the interlocking microstructure between Cu layer and intermediate layer contributes to the improved bonding strength. This new method realizes the metallization of AlN ceramic with high interfacial bonding strength and low cost compared with the traditional joining technology, and provides a potential reference for the surface metallization of inert material.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2017
·
IF 2.084
Guanghao Li,Yang Zhao,Jiao Xu,Zhiyong Mao,Jingjing Chen,Dajian Wang
Two strategies, deviation of stoichiometry and addition of flux, were employed in this work to suppress the emergence of AlN impurity in the synthesis of CaAlSiN 3 :Eu 2+ phosphors under condition of atmospheric pressure. The influence of Al atoms deviation from ideal stoichiometry and SrF 2 flux addition on the suppression of AlN impurity and their resultant photoluminescence properties are investigated for CaAlSiN 3 :Eu 2+ phosphors. For a special Eu 2+ doping concentration (0.02 mol), AlN impurity was suppressed effectively when Al element deviation is 0.2 mol (CaAl 0.8 SiN 3 ) and the SrF 2 flux addition is 7 wt% during preparation of CaAlSiN 3 :Eu 2+ phosphors, respectively. The luminescent properties of CaAlSiN 3 :Eu 2+ phosphors are found to be enhanced significantly owing to the suppression of AlN impurity. In addition, the suppression mechanisms of AlN impurity in atmospheric pressure-synthesized CaAlSiN 3 :Eu 2+ phosphors are discussed. These results indicate the promising prospect for our proposed strategies in preparing high performance CaAlSiN 3 :Eu 2+ phosphors under the condition of atmospheric pressure.
研究领域:
材料科学
·
无机化学
·
固体发光
·
功能材料
·
光电子学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）