Ultra-high creep resistant SiC ceramics prepared by rapid hot pressing. Issue 3 (March 2022)

• Record Type: Journal Article
• Authors: Šajgalík, Pavol; Cheng, Zanlin; Han, Xuxu; Zhang, Chengyu; Hanzel, Ondrej; Sedláček, Jaroslav; Orlova, Tatyana; Zhukovskyi, Maksym; Mukasyan, Alexander S.
• Is Part Of: Journal of the European Ceramic Society. Volume 42:Issue 3(2022)
• Page Start: 820
• Page End: 829
• Publication Date: 2022-03
• Subjects: Silicon carbide -- Rapid hot pressing -- Compressive creep -- Microstructure -- Creep mechanism; 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.2021.11.010
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: The high-temperature compression creep of additive-free β/α silicon carbide ceramics fabricated by rapid hot pressing (RHP) was investigated. The creep tests were accomplished in vacuum at temperature range 1500 °C–1750 °C and compressive loads of 200 MPa to 400 MPa. Under investigated condition the RHP ceramics possessed the lowest creep rate reported in the literature. The observed strain rates changed from 2.5 × 10 −9 s −1 at 1500 °C and a lowest load of 275 MPa to 1.05 × 10 −7 s −1 at 1750 °C and a highest load of 400 MPa. The average creep activation energy and the stress exponent remain essentially constant along the whole range of investigated parameters and were 315 ± 20 kJ∙mol −1, and 2.22 ± 0.17, respectively. The suggested creep mechanism involves GB sliding accommodated by GB diffusion and β−α SiC phase transformation.