International Journal of Applied Ceramic Technology
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2024
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IF 1.8
Dian Zhang,Xuan Liu,Yijun Liu
Conventional aluminum nitride (AlN) ceramics exhibited insufficient mechanical properties expected from their potential applications in the presence of dynamic loads and intensive stresses caused by thermal shock. In this study, the mechanical properties of AlN ceramics were enhanced by toughening them using AlN whiskers (AlN w ) via gel casting followed by low-temperature sintering at 1650°C. The addition of AlN w simultaneously increased the bending strength, toughness and thermal conductivity of the AlN ceramics. The maximum values of the bending strength, toughness, and thermal conductivity of 9.0 wt% AlN w /AlN were 303.92 MPa, 3.92 MPa·m 1/2 and 186.53 W·m −1 ·K −1 , respectively, which were higher than those of the AlN ceramics by 39.93%, 61.31% and, 15.61%, respectively. The AlN w in AlN w /AlN ceramics tightly bonded with the ceramic matrix, leading to two characteristic toughening mechanisms in the ceramics: crack pinning and deflection at irregular grain boundaries caused by doped whiskers, as well as bridging and stress relaxation caused by whiskers incorporated with the grains. Moreover, the one-dimensional morphology of AlN w can provide a channel for quick photon transport, thereby enhancing the thermal conductivity of AlN w /AlN.
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 THE EUROPEAN CERAMIC SOCIETY
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2022
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IF 6.364
Liang Wang,Wei-Ming Guo,Peng-Fei Sheng,Li-Fu Lin,Xiao Zong,Shang-Hua Wu
A new type of non-oxide sintering additive of YH 2 was introduced for the fabrication of AlN ceramics with high thermal conductivity and flexural strength . The effects of YH 2 addition (0–5 wt%) on the phase composition, densification, microstructure, thermal conductivity and flexural strength of pressureless sintered AlN ceramics were investigated and compared with those Y 2 O 3 -added samples (1–5 wt%). The addition of 1 wt% YH 2 led to an in-situ reduction reaction with oxygen impurities, the formation of Y 2 O 3 and finally the formation of yttrium aluminate, which in turn improved densification and microstructure. A high flexural strength (408.69 ± 28.23 MPa) was achieved. The addition of 3 wt% YH 2 increased the average grain size and purified the lattice. All these effects are believed to help achieve a high thermal conductivity of 184.82 ± 1.75 W·m −1 ·K −1 . Although the thermal conductivity was close to the value of 3 wt% Y 2 O 3 -added sample, its strength was much increased to 381.53 ± 43.41 MPa. Meanwhile, it demonstrated a good combination of the thermal conductivity and flexural strength than the values reported in some literature. However, further increasing the YH 2 addition to 5 wt% resulted in a high N/O ratio that inhibited the densification behavior of AlN ceramics. The current study showed that AlN ceramics with excellent thermal and mechanical properties could be obtained by the introduction of a suitable YH 2 additive.
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
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
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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
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电子工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NON-CRYSTALLINE SOLIDS
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2024
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IF 3.2
Bo Wang,Zihao Pan,Ziyan Zhao,Bo Zhou,Xuejian Liu,Zhengren Huang,Yan Liu
In this paper, we designed two series of the ZnO-B 2 O 3 -SiO 2 (ZBS) glass to explore their applicability for joining AlN ceramic. The density, flexural strength, structure, characteristic temperature, coefficient of thermal expansion (CTE) and crystallization behavior of the ZBS glass with varying ZnO and B 2 O 3 content were systematically studied. The results show that as B 2 O 3 content increase, the glass network is disrupted with the transition from three-dimensional shelf-like structure [BO 4 ] to two-dimensional layers [BO 3 ], increasing the number of the broken bonds, while an increase in ZnO results in a more compact glass network structure. We also found that both glass transition temperature (T g ) and softening temperature (T S ) exhibit a declining trend with the increase in B 2 O 3 and ZnO. Zn 2 SiO 4 and ZnAl 2 O 4 , began to precipitate after heat treatments in all the samples except 60ZnO-30B 2 O 3 –10SiO 2 (abbreviated as B30), where the diffraction peaks do not appear in Zn 2 SiO 4 but in Zn 4 B 6 O 13 . Notably, Zn 2 SiO 4 is the main phase for most samples while the main phase of B30 sample is ZnAl 2 O 4 . The CTE increases from 4.6 to 5.03 (× 10 –6 / °C) and 4.23 to 4.73 (× 10 –6 / °C) with an increase of B 2 O 3 and ZnO content, respectively. Among these, the CTE of B30 sample is compatible with that of AlN ceramic substrate. The optimal shear strength, 60.32±10.26 MPa, was achieved with B30 samples at 750 °C. The high strength was attributed to the interfacial reaction that leads to strong chemical bonding and the uniform distribution of the ZnAl 2 O 4 in the interlayer, which reinforces the strength of the interlayer itself.
研究领域:
材料科学
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无机非金属材料
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
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2024
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IF 5.1
Bo Wang,Ziyan Zhao,Zihao Pan,Xuejian Liu,Zhengren Huang,Yan Liu
The ZnO–Al 2 O 3 –B 2 O 3 –SiO 2 (ZABS) glass powder was designed and innovatively employed to join AlN ceramics. The crystallization, thermal expansion and wettability behavior of the ZABS glass and glass-ceramic were investigated. The results shows that Zn 3 B 2 O 6 , ZnSiO 4 and Zn 4 B 6 O 13 were precipitated after heat treatments at different temperature, respectively, resulting in a variation in the coefficient of thermal expansion (CTE) of the ZABS glass ceramic. Then guided by the wetting behavior on the AlN ceramic substrate, the joining of the AlN ceramics by ZABS glass at various temperatures and holding times were conducted. Notably, Zn 3 B 2 O 6 was identified to be the primary product in the joints bonded at temperature of 700–800 °C due to the crystallization within the glass and no discernible reaction was observed between the substrate and the interlayer, while ZnSiO 4 was observed at the periphery of Zn 3 B 2 O 6 after 750 °C. Moreover, the crystalline phase Zn 3 B 2 O 6 gradually grew with the temperature and holding time increasing as the glassy phase gradually diminished, resulting in a reduction of the strength and reliability of the joints. The optimal flexural strength of the joints was 156 ± 11MPa at 700 °C for 30min. The reason for the high strength can be attributed to the interactions between the glass precipitated crystalline phase interlocking each other and the glass phase tightly bonded with the crystalline phase.
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
MATERIALS & DESIGN
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2017
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IF 4.364
Meng Fei,Renli Fu,Simeon Agathopoulos,Jun Fang,Caixia Wang,Haitao Zhu
A novel method for preparing aluminum/aluminum nitride ceramics (Al/AlN) substrates is proposed in this paper. The method included two processes: (1) the surface of AlN was coated with a CuO thick film and sintered; (2) Al foil was put on the pretreated (in process 1) AlN surface and bonded to AlN through pre-heating at 400 °C and final heating at 660 °C in N 2 -H 2 reduction atmosphere. The experimental results obtained by optical and scanning electron microscope (SEM) observations as well as by X-ray diffraction analysis at the cross-sections of the joints and the fracture surfaces , suggest that the reaction mechanism starts with the reaction of CuO with AlN to form CuAlO 2 , when the AlN coated with CuO is heat-treated at high temperature. A Cu layer is produced by the reduction of CuO and Cu diffuses in the Al foil, forming strong Al/AlN joints. Elongated crystals of Al 2 Cu are developed in the reaction zone at the interface between Al and AlN. The results of mechanical tests showed that the peeling-off strength of the Al foil from the surface of the AlN substrate reached a value of 15.4 MPa for the Al/AlN couples produced after 30 min of heat treatment at 660 °C.
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
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
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2021
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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
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能源工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）