Oxidation behavior and microstructure evolution of SiC-ZrB2-ZrC coating for C/C composites at 1673 K. Issue 11 (15th August 2016)

• Record Type: Journal Article
• Authors: Li, Lu; Li, Hejun; Shen, Qingliang; Lin, Hongjiao; Feng, Tao; Yao, Xiyuan; Fu, Qiangang
• Is Part Of: Ceramics international. Volume 42:Issue 11(2016)
• Page Start: 13041
• Page End: 13046
• Publication Date: 2016-08-15
• Subjects: A. Sintering -- B. Composites -- C. Corrosion -- D. SiC; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2016.05.083
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: To protect carbon/carbon (C/C) composites against oxidation, a SiC-ZrB2 -ZrC coating was prepared by the in-situ reaction between ZrC, B4 C and Si. The thermogravimetric and isothermal oxidation results indicated the as-synthesized coating to show superior oxidation resistance at elevated temperatures, so it could effectively protect C/C composites for more than 221 h at 1673 K in air. The crystalline structure and morphology evolution of the multiphase SiC-ZrB2 -ZrC coating were investigated. With the increase of oxidation time, the SiO2 oxide layer transformed from amorphous to crystalline. Flower-like and flake-like SiO2 structures were generated on the glass film during the oxidation process of SiC-ZrB2 -ZrC coating, which might be ascribed to the varying concentration of SiO. The oxide scale presented a two-layered structure ~130 µm thick after oxidation, consisting of a SiO2 -rich glass layer containing ZrO2 /ZrSiO4 particles and a Si-O-Zr layer. The multiphase SiC-ZrB2 -ZrC ceramic coating exhibited much better oxidation resistance than monophase SiC, ZrB2 or ZrC ceramic due to the synergistic effect among the different components.