A novel strategy for synthesizing porous ZrB2-SiC ceramics via boro/carbothermal reaction process templated pore-forming approach. Issue 9 (August 2023)

• Record Type: Journal Article
• Authors: Wang, Shijie; Chen, Haonan; Li, Yong; Ma, Haoxuan; Liu, Xinhong; Zhang, Shaowei; Jia, Quanli
• Is Part Of: Journal of the European Ceramic Society. Volume 43:Issue 9(2023)
• Page Start: 3905
• Page End: 3916
• Publication Date: 2023-08
• Subjects: Porous ceramics -- ZrB2-SiC -- Boro/carbothermal reaction -- Gas-releasing -- Templated pore-forming method; 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.2023.02.070
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: In this work, pure ZrB2 -SiC composite powders were obtained using ZrO2, SiO2, B4 C and carbon black as raw materials via a boro/carbothermal reduction (BCTR) reaction process at 1500 °C for 2 h in vacuum condition. Based on this finding, porous ZrB2 -SiC ceramics were in-situ synthesized via a novel and facile boro/carbothermal reaction process templated pore-forming (BCTR-TPF) method. The phase composition, linear shrinkage, and pore size distribution were also methodically studied. Results show that the porous ZrB2 -SiC ceramics with controllable porosity of 67–78%, compressive strength of 0.2–9.8 MPa and thermal conductivity of 1.9–7.0 W·m −1 K −1 can be fabricated by varying of ZrO2 and B4 C particle sizes. The formation of ZrB2 grains was controlled via solid-solid and solid-liquid-solid growth mechanisms, the growth process of SiC grains was mainly regulated by solid-solid, vapor-vapor and vapor-solid growth mechanisms during the overall synthesis process. Finally, the pore-forming mechanism of porous samples prepared via the BCTR-TPF method was gases combined with template pore-forming mechanism, i.e., B4 C and carbon black acted as pore-forming templates, and gaseous products generated in the BCTR reaction were also applied as gas pore-forming agent.