Crack-healing in ytterbium silicate filled with silicon carbide particles. Issue 15 (December 2020)

• Record Type: Journal Article
• Authors: Kunz, Willy; Klemm, Hagen; Michaelis, Alexander
• Is Part Of: Journal of the European Ceramic Society. Volume 40:Issue 15(2020)
• Page Start: 5740
• Page End: 5748
• Publication Date: 2020-12
• Subjects: Crack-healing -- Rare-earth silicates -- Reactive particles; 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.2020.06.032
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: A study on the influence of the silicate composition on the self-healing ability of a promising environmental barrier coating (EBC) material is reported. The EBC material consists of silicon carbide particles dispersed in a ytterbium silicate matrix. The composition of the silicate was varied from pure monosilicate to pure disilicate including a mixture of 50 vol-% of both phases. Pre-cracked specimens were mechanically tested before and after thermal annealing in air at 1400 °C accompanied by microstructural investigations. It is shown, that the self-healing mechanism is based on the application of compressive surface stresses due to graded oxidation of the SiC particles. With increasing amount of disilicate strength and self-healing ability increase.