Role of boron addition on phase composition, microstructural evolution and mechanical properties of nanocrystalline SiBCN monoliths. Issue 4 (April 2018)

• Record Type: Journal Article
• Authors: Li, Daxin; Yang, Zhihua; Jia, Dechang; Duan, Xiaoming; Zhou, Yu; Yu, Dongli; Tian, Yongjun; Wang, Zihuan; Liu, Yinglong
• Is Part Of: Journal of the European Ceramic Society. Volume 38:Issue 4(2018)
• Page Start: 1179
• Page End: 1189
• Publication Date: 2018-04
• Subjects: SiBCN -- BN(C) -- Microstructural evolution -- Mechanical alloying -- Mechanical properties; 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.2017.11.054
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: Nanocrystalline SiBCN monoliths with the same Si/C/N mole ratio and various boron additions ranged from 0 to 3.0 mol were prepared by mechanical alloying plus reactive hot pressing methods. Correction of boron content and microstructural/morphological evolution was investigated in detail by XRD, SEM, TEM and STEM-EDX structure characterization. Except for SiC and BN(C), boron addition contributes to B x C formation. Besides, boron addition promotes the crystallization of SiC, leading to the formation of poor crystallinity of spherical structures in inner SiC. Furthermore, boron addition significantly promotes the grain growth of SiC and B x C and therefore increases the relative volume ratios of B x C/BN(C) and B x C/SiC. Amorphous-like BN(C) changes to belt-like structures as boron addition increases. The new formed B x C effectively contributes to the improvement of Vicker's hardness while pull-out of BN(C) belt-like structures benefits the fracture toughness.