Self-healing behavior and strength recovery of ytterbium disilicate ceramic reinforced with silicon carbide nanofillers. Issue 10 (August 2019)

• Record Type: Journal Article
• Authors: Nguyen, Son Thanh; Nakayama, Tadachika; Suematsu, Hisayuki; Iwasawa, Hirokazu; Suzuki, Tsuneo; Otsuka, Yuichi; He, Lingfeng; Takahashi, Tsuyoshi; Niihara, Koichi
• Is Part Of: Journal of the European Ceramic Society. Volume 39:Issue 10(2019)
• Page Start: 3139
• Page End: 3152
• Publication Date: 2019-08
• Subjects: Crack-healing -- Silicon carbide -- Ceramic -- Ytterbium silicate -- Nanofiller; 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.2019.03.040
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: Environmental barrier coatings (EBCs) are necessary to protect SiC/SiC ceramic components against oxidation and hot corrosion in high-temperature applications. The volatilization of SiO2 in SiC-reinforced materials is a major obstacle for the implementation of these self-crack-healing ceramics. The Yb2 Si2 O7 -Yb2 SiO5 -SiC composite is known as a self-healing material that can help to avoid this SiC recession. In this research, the crack-healing behavior of this composite is investigated by using pre-cracking followed by annealing in an oxidizing environment. The crack-healing mechanism is explored and elucidated as a function of the filler morphology, crack size, annealing time, and annealing temperature. The two main crack-healing mechanisms are the filling of cracks with SiO2 glass and the volume expansion of Yb2 Si2 O7 induced by the reaction between SiO2 and Yb2 SiO5 . Full crack recovery is achieved with only 10 vol% SiC, with evidence from XRD and EDS analyses. SiC nanoparticulates are more efficient fillers than nanofibers and nanowhiskers.