Microstructure and mechanical behaviour of transient liquid phase spark plasma sintered B4C–SiC–TiB2 composites from a B4C–TiSi2 system. Issue 8 (15th April 2021)

• Record Type: Journal Article
• Authors: Wang, Yang; Liu, Qiang; Zhang, Biao; Zhang, Haoqian; Jin, Yicheng; Zhong, Zhaoxin; Ye, Jian; Ren, Yuhan; Ye, Feng; Wang, Wen
• Is Part Of: Ceramics international. Volume 47:Issue 8(2021)
• Page Start: 10665
• Page End: 10671
• Publication Date: 2021-04-15
• Subjects: B4C–SiC–TiB2 composites -- TiSi2 -- Spark plasma sintering -- Mechanical properties -- Toughening mechanism; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2020.12.180
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: Almost fully-dense B4 C–SiC–TiB2 composites with a high combination of strength and toughness were prepared through in situ reactive spark plasma sintering using B4 C and TiSi2 as raw materials. The densification, microstructure, mechanical properties, reaction, and toughening mechanisms were explored. TiSi2 was confirmed as a reactive sintering additive to promote densification via transient liquid-phase sintering. Specifically, Si formed via the reaction between B4 C and TiSi2 that served as a transient component contributed to densification when it melted and then reacted with C to yield more SiC. Toughening mechanisms, including crack deflection, branching and bridging, could be observed due to the residual stresses induced by the thermoelastic mismatches. Particularly, the introduced SiC–TiB2 agglomerates composed of interlocked SiC and TiB2 played a critical role in improving toughness. Accordingly, the B4 C–SiC–TiB2 composite created with B4 C-16 wt% TiSi2 achieved excellent mechanical performance, containing a Vickers hardness of 33.5 GPa, a flexural strength of 608.7 MPa and a fracture toughness of 6.43 MPa m 1/2 .