SiC/SiC mini-composites with yttrium disilicate fiber coatings: Oxidation in steam. Issue 5 (May 2021)

• Record Type: Journal Article
• Authors: Boakye, Emmanuel E.; Key, Thomas S.; Mogilevsky, Pavel; Opeka, Samuel J.; Corns, Randall; Hay, Randall S.; Cinibulk, Michael K.
• Is Part Of: Journal of the European Ceramic Society. Volume 41:Issue 5(2021)
• Page Start: 3132
• Page End: 3140
• Publication Date: 2021-05
• Subjects: Ceramic matrix composites -- SiC fiber -- RE2Si2O7oxide coating -- Weak interphase; 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.2020.09.033
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: Solutions of YPO4 were used to precipitate YPO4 on pre-oxidized Hi-Nicalon-S SiC fibers. Tows of the coated fibers were then infiltrated with a preceramic polymer loaded with SiC particles to form mini-composites. During pyrolysis of the matrix, SiO2 and YPO4 on the fibers reacted and formed a Y2 Si2 O7 fiber matrix interphase. Mini-composites were exposed to steam at 1000 °C for 10, 50, and 100 h, tensile tested, and the effect of oxidation in steam on the functionality of the Y2 Si2 O7 fiber coating was investigated. The minicomposites oxidized at 1000 °C for 10 h retained 100 % of their unoxidized strength, and those oxidized for 50 and 100 h retained 92 % and 90 % of unoxidized strength, respectively. Strength retention and fiber pullout in both unoxidized and oxidized minicomposites suggests that the Y2 Si2 O7 interphase was effective in maintaining a weak fiber-matrix interface.