Pressureless-sintered boron nitride nanosheets/glass composite ceramics for excellent mechanical, dielectric and thermo-conductive performances. Issue 9 (August 2023)

• Record Type: Journal Article
• Authors: Qiao, Wei; Yang, Jingwen; Qiao, Jiaxiao; Gao, Hejun; Li, Zexia; Wang, Peng; Cao, Chaochao; Zhang, Jun; Xue, Yanming; Tang, Chengchun
• Is Part Of: Journal of the European Ceramic Society. Volume 43:Issue 9(2023)
• Page Start: 3998
• Page End: 4007
• Publication Date: 2023-08
• Subjects: Boron nitride nanosheets -- Glass -- Multiphase ceramics -- Thermal management -- Pressureless sintering; boron nitride nanosheets (BNNSs) -- glass (GS) -- dielectric constant (DC) -- thermal conductivity (TC); Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2023.02.072
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: Because they have a high application potential in the thermal management of insulation environments, high-quality hexagonal boron nitride (h-BN)-based multiphase ceramics have been highly desired. However, so far, their synthesis is still full of challenges. Here, a kind of boron nitride nanosheets (BNNSs)/glass (GS) composite ceramics was prepared by a pressureless sintering method at a lower temperature of 900 °C. Due to a tightly bonded interaction between BNNSs and GS, the formed BNNSs/GS ceramics exhibit excellent multifunction performance. They have an outstanding compressive strength in the range of 19 ∼ 64 MPa and Vickers hardness ranging from 50 to 179 HV. For the BNNSs/GS ceramics with BNNS's filling fraction of 90 wt%, their maximum side-surface TC values are 12.01 ± 0.18 W m −1 K −1 at 25 °C and 13.64 ± 0.37 W m −1 K −1 at 300 °C, respectively. In the ultra-high frequency range of 26.5 ∼ 40 GHz, the dielectric constant values of the BNNSs/GS ceramics are primarily between 2 and 3, and the corresponding loss tangent values are < 0.3. In addition, based on the remarkable integrity of their structure, these BNNSs/GS ceramics exhibit outstanding thermal-shock stability and prominent thermal management capacity during lots of heating/cooling-testing cycles. Therefore, we believe this kind of BNNSs/GS ceramic system will have great application potential in the new-generation thermal management and/or insulation packaging fields.