Effects of Microwave Sintering Temperature and Holding Time on Mechanical Properties and Microstructure of Si3N4/n-SiC ceramics

Li Qiao; Zhenhua Wang; Taiyi Lu; Juntang Yuan

doi:10.3390/ma12233837

Effects of Microwave Sintering Temperature and Holding Time on Mechanical Properties and Microstructure of Si₃N₄/n-SiC ceramics

Materials (Basel). 2019 Nov 21;12(23):3837. doi: 10.3390/ma12233837.

Authors

Li Qiao¹, Zhenhua Wang^{1

2}, Taiyi Lu^{1

2}, Juntang Yuan^{1

2}

Affiliations

¹ School of Mechanical Engineering, Nanjing University of Science & Technology, Nanjing 210094, China.
² Collaborative Innovation Center of High-End Equipment Manufacturing Technology (Nanjing University of Science & Technology), Ministry of Industry and Information Technology, Nanjing 210094, China.

Abstract

The n-SiC (nanometer SiC) is added to be the additive in order to improve the mechanical performance of Si₃N₄ ceramics. A microwave sintered the ceramics at different temperature and holding times. The results shows that the Si₃N₄/n-SiC ceramics (85 wt% Si₃N₄ + 5 wt% n-SiC + 5 wt% Al₂O₃ + 5 wt% Y₂O₃) have the best mechanical properties at 1600 °C, which is beneficial to the densification and β-Si₃N₄ phase formation for 10 min: the density, hardness, and fracture toughness were 97.1%, 14.44 GPa, and 7.77 MPa·m^1/2, which increased by 2.8%, 7.0%, and 13.1%, respectively, when compared with the ceramics (90 wt% Si₃N₄ + 5 wt% Al₂O₃ + 5 wt% Y₂O₃).

Keywords: Si3N4 ceramics; mechanical properties; microstructure; microwave sintering; n-SiC.