标题：Influence of pores distribution on fracture toughness of FeSi/Si3N4composite
作者：Sun, Xiaolin ;Sun, Kangning ;Li, Aimin ;Cheng, Fuming ;Cheng, Yuan
作者机构：[Sun, Xiaolin ;Sun, Kangning ;Li, Aimin ;Cheng, Fuming ;Cheng, Yuan ] Key Laboratory for Liquid-Solid Structure Evolution and Processing of Materials, 更多
来源：International Journal of Refractory Metals and Hard Materials
摘要：FeSi/Si3N4ceramic composite was fabricated by hot pressing technique, using α-Si3N4and Fe3Al. The toughening effect of Fe3Al on the Si3N4matrix is explained on the basis of microstructural characterizations and schematic representations. Results indicate that the reaction between α-Si3N4and Fe3Al results in the formation of FeSi and sialon phases at the interface. Both phases effectively restrain coalescence and movement of the gaseous reaction product, N2, retaining it in situ to form small separated pores. The dominant toughening effect of these pores reduces the interface bonding strength, consumes the crack propagation energy, and decreases the stress-concentration at the crack tip, thereby improving the fracture toughness of the matrix. © 2013 Elsevier Ltd.