High toughness and R-curve behaviour of laminated SiC/graphite ceramics. Issue 14 (1st October 2020)

• Record Type: Journal Article
• Authors: Wei, Chuncheng; Liu, Zhen; Zhang, Zhongya; Ma, Xuefei; Wang, Peng; Li, Shuang; Liu, Lanyong
• Is Part Of: Ceramics international. Volume 46:Issue 14(2020)
• Page Start: 22973
• Page End: 22979
• Publication Date: 2020-10-01
• Subjects: Laminated ceramics -- SiC -- Toughness -- Fracture -- Interface layer; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2020.06.072
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: Bionic laminated SiC/graphite ceramics were fabricated by tape casting. The mechanical properties and R-curve behaviour of the laminated SiC/graphite ceramics were evaluated and compared with those of monolithic SiC ceramics. The toughness of the laminated SiC/graphite ceramics was 9.48 MPa m 1/2, which was 3 times that of the monolithic SiC ceramics (3.56 MPa m 1/2 ). The improvement in the toughness was mainly due to the deflection of the crack at the graphite interface layer and the pull-out of the graphite sheet, which consumed a lot of fracture work. In addition, the laminated SiC/graphite ceramics exhibited rising R-curve behaviour. The excellent damage resistance of the laminated SiC/graphite ceramics was attributed to the indentation surface collapse caused by the porous structure of the graphite interface layer, which consumed quite a large amount energy and reduced the formation of microcracks. Meanwhile, the step-like fracture mode prolonged the crack propagation path and avoided catastrophic damage.