AUTHOR=Cao Ting , Li Xiaoqiang , Li Jingmao , Huang Yang , Qu Shengguan , Yang Chao , Liang Liang , Song Tao 

TITLE=Mechanical Properties of WC-Si3N4 Composites With Ultrafine Porous Boron Nitride Nanofiber Additive

JOURNAL=Frontiers in Materials

VOLUME=8

YEAR=2021

URL=https://www.frontiersin.org/journals/materials/articles/10.3389/fmats.2021.534407

DOI=10.3389/fmats.2021.534407

ISSN=2296-8016

ABSTRACT=<p>WC-10 wt.% Si<sub>3</sub>N<sub>4</sub> composites toughened with ultrafine porous boron nitride nanofiber (0, 0.01, 0.05, 0.1, and 0.15 wt.%) were prepared for the first time by spark plasma sintering. Compared with the WC-Si<sub>3</sub>N<sub>4</sub> composite sintered in the same condition, the obtained WC-10 wt.% Si<sub>3</sub>N<sub>4</sub> composites with ultrafine porous boron nitride were found to possess better hardness and fracture toughness. In addition, the Si<sub>3</sub>N<sub>4</sub> phase in the UPBNNF toughened composites did not exhibit traditional catastrophic fracture as indicated in most investigations. In this study, the phenomena are discussed, and a probable mechanism is elucidated. It is deduced that the approach could be extended to materials with a feature of internal liquid phase during the sintering process and could improve hardness and fracture toughness.</p>