Silicon nitride ceramics fracture toughness

Silicon nitride ceramics should have high flexural strength and fracture toughness at room temperature and good creep resistance at elevated temperatures. Because these properties are determined by the microstructure of these ceramics, further improvement of these ceramics is possible through alloy design. The following sections will be devoted to micro-... 

Lai and Tien [26] (Fig. 15) have shown that the flexure strength and fracture toughness of silicon nitride ceramics depends on the aspect ratio... 

E. H. Lutz and M. V. Swain, Fracture Toughness and Thermal Shock Behavior of Silicon Nitride Ceramics, J. Am. Ceram. Soc., 75, 67-70 (1992). 

T. Kawashima, H. Okamoto, H. Yamamoto, A. Kitamura, Grain size dependence of the fracture toughness of silicon nitride ceramics, /. Ceram. Soc. Jpn.Int. Ed., 99 310-13 (1991)... 

The research efforts made to tailor ceramic microstructure so as to improve properties are described in this chapter. Although many material properties are affected by the microstructure, the emphasis here is placed on the mechanical properties, especially strength and fracture toughness. In particular, attention is focused on silicon nitride ceramics, the mechanical properties of vhich have been improved substantially through microstructure tailoring during the past tv o decades. 

Excellent high temperature properties [1] Strength, creep, fracture toughness, hardness, corrosion/erosion resistance, good thermal schock resistance make silicon nitride ceramics ideal materials for highly stressed structural applications at high temperatures such as internal combustion engines and gas turbines [2,3]. 

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