ZHANG Yuning¹, YAN Fengyun^{1, 2}, WU Laner³

(1.State Key Laboratory of Gansu Advanced Non- ferrous Metal Materials , Lanzhou University of Technology, 730050)

(2. Key Laboratory of Non- ferrous Metal Alloys and Proces s ing of the Minis try of Education, Lanzhou University of Technology, 730050)

(3.The Northwes t Second University for Nationalities , Yinchuan, 750021)

Abstract: In this paper, the hardness and fracture toughness of SiC- Si₃N₄ composite materials with different SiC content were investigated. The results show that the properties of SiC- Si₃N₄ composite with 15wt% SiC content were significantly superio compared with others . It is also indicated that the properties of the composite materials made from mixture powder were slightly better than those made from SHS powder. Also, the relation between microstructure and the toughening mechanism was discussed according to the SEM-analys is of SiC- Si₃N₄ composite.

Key words: SiC- Si₃N₄ composite materials , hardness , fracture toughness , microsructure