Journal:Journal of the American Ceramic Society
Abstract:The in situ formation of carbon fillers has been demonstrated as an effective strategy to eliminate the agglomeration of carbon fillers in ceramic composites. In this study, combustion synthesis was employed to in situ incorporate carbon into a ZrO2–SiO2 ceramic powder using CO2 gas as the carbon source and magnesium powder as the exothermic medium. The resulting disordered carbon is uniformly distributed within the powder matrix. Furthermore, magnesium element is simultaneously incorporated into the powder as a byproduct. The co-presence of carbon and magnesium elements synergistically enhances the solid-state reaction between ZrO2 and SiO2 during sintering, facilitating the formation of ZrSiO4 at a significantly reduced temperature of 1080°C. Meanwhile, the solid-state reaction significantly promotes the densification of the ceramic composite. The incorporated carbon exhibits strong bonding with the ceramic matrix and remains stable within the matrix up to at least 1000°C. Compared with conventional ZrSiO4, the ZrSiO4 phase formed in this study exhibits much lower decomposition temperature in range of 1000°C–1200°C. Molten copper exhibits pronounced corrosion toward the ceramic composite, primarily through reactions with the SiO2 phase released from the decomposition of ZrSiO4.
Co-author:Bohan Wang, Zihua Lei, Mingxi Deng
First Author:Le Fu*
Correspondence Author:Guanghua Liu*
Volume:109
Page Number:e71194
Translation or Not:no
Links to published journals:https://ceramics.onlinelibrary.wiley.com/doi/10.1111/jace.71194