Microstructure of silicon nitrides

Turan, S. and Knowles, K.M., (1995), A comparison of the microstructure of silicon nitride-silicon carbide composites made with and without deoxidized starting material , J. Microscopy, YU (3), 287-304. 

Fig. 17. Microstructure of silicon nitride ceramics sintered at 1900°C for 2 h under 10 atm of nitrogen (27).

T. Kusunose, T. Sekino, Y.H. Choa, and K. Niihara, Fabrication and Microstructure of Silicon Nitride/Boron Nitride Nanocomposites, J. Am. Ceram. Soc., 85, 2678-88(2002). 

These experimental data suggest that P-SijN4 nucleation has no influence on the microstructure of silicon nitride materials under common sintering conditions and using common powders. 

Figure 8.9 Microstructures of silicon nitrides, (a) a-powder with 2 wt% 3-seed crystals, tape-cast and gas-pressure-sintered at 1850°C for 6 h (b) a-powder without 3-seed crystals, hot-pressed at 1750°Cfor2 h (c) a-powderwithout...

Parr NL, Martin GF, May ERW (1960) Preparation, Microstructure and Mechanical Properties of Silicon Nitride. In Popper P (ed) Special Ceramics. Heywood, London, p 102... 

Becher PF, Hwang SL, Lin HT, Ticgs TN (1994) Microstructural contributions to the fracture resistance of silicon nitride ceramics. In Hoffmann MJ, Petzow G (eds) Tailoring of Mechanical Properties of Si3N4 Ceramics, NATO ASI Ser E Vol. 276, Kluwer Academic Publishers, Dordrecht, p 87... 

Becher PF, Lin HAT, Hwang SL, Hoffmann MJ, Chen IW (1993) The influence of microstructure on the mechanical behavior of silicon nitride ceramics. In Chen IW, Becher P, Mitomo M, Petzow G, Yen TS (eds) Silicon Nitride Ceramics-Scientific and Technological Advances. MRS Symposium Proc 287, MRS Pittsburgh, p 147... 

Emoto H, Hirotsuri H (1999) Microstructure Control of Silicon Nitride Ceramics Fabricated from a Powder Containing Fine /(-Nuclei. In Niihara K, Sekino T, Yasuda E, Sasa T (eds) The Science of Engineering Ceramics II Key Eng Mat 161-163. Trans Tech Publications, Switzerland, p 209... 

Nishimura N, Masuo E, Takita K (1991) Effect of Microstructural Oxidation on the Strength of Silicon Nitride after High Temperature Exposure. In Carlsson T, Johansson T, Kahlman T (eds) Proc 4th Int Symp Ceram Mater Components for Engines. Elsevier, London, p 1139... 

Wayne, S.F. and Buljan, S.T. Microstructure and wear resistance of silicon nitride composites , in Friction and Wear of Ceramics, ed. S. Jahanmir, pp. 261-285, Marcel Dekker, New York (1994). 

Shen, Z J., Zhan, Z., Peng, 11, el a ., Formation of tough interlocking microstructures in silicon nitride ceramics by dynamic ripening, Nature, 2002, 417 266. 

Kondo, N., Suzuki, Y., and Ohji, T., Superplastic sinter-forging of silicon nitride with anisotropic microstructure formation , J. Am. Ceram. Soc., 1999, 82, 1067-9. 

Skibska, M., Szulc, A., Mukasyan, A. S., and Rogachev, A. S., Microstructural peculiarities of silicon nitride formation under high nitrogen pressures. Part I Hje influence of initial Si particle size distribution on SiaN4 SHS morphology. Int. J. SHS, 2,39 (1993a). 

Fig. 15. Microstructural dependence of flexural strength and fracture toughness of silicon nitride ceramics. The composition of these specimens was 90 wt % Si3N4-10 wt % Y3A15Op (27).

Silicon nitride ceramics are one of the most promising materials for structural applications. The properties of the silicon nitride ceramics depend on the phases present and their microstructures. This paper describes how to approach microstructural design of these materials by using the phase equilibrium diagrams of silicon nitride-metal oxide systems. 

Fig. 31. Microstructural parameters and density of silicon nitride sintered at 1800°C for 2 h + 1850°C for 2 h as a function of (a) the additive concentration and (b) the amount of A1203 added to Si3N4 + 15 % Y203. After Wotting and Ziegler [ 139. Reproduced with permission of Elsevier Science Publishing Co., New York.

F. Monteverde and A. Bellosi, Effect of the Addition of Silicon Nitride on Sintering Behaviour and Microstructure of Zirconium Diboride, Scr. Mater., 46(3], 223-228 (2002). 

The adaptation of silicon nitride materials to various applications leads to an increase in the variety of microstructures (see Fig. 1). This was the impetus for... 

Silicon nitride-based ceramics are promising engineering materials for application under corrosive and wear conditions [135-142]. However, the use of silicon nitride materials in hot acids under hydrothermal conditions and in bases is often limited by degradation of the materials. This is the impetus for current efforts for better understanding of the influence of the microstructure on the corrosion behaviour of silicon nitride materials and to improve the materials behaviour on its basis. Up to now, only a small amount of data about the mechanisms of corrosion and pitting formation exists. 

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