Silicon nitride ceramic effect

All silicon nitride ceramics are derived from synthetic materials, exclusively. The first report on the synthesis of Si3N4 was in 1859 by Sainte-Claire Deville and Wohler [3]. Among the problems of greatest concern to chemists in those days was the utilisation of atmospheric nitrogen for agricultural and industrial purposes. In particular, there was a need for a highly effective... 

Silicon nitride ceramics are not merely only one material but several classes of materials. All of them are multiphased, i.e., they exhibit a heterogeneous microstructure which has formed during sintering (Sect. 6). Therefore in all classes a large variety of properties is predominant and as a consequence also a large variety of potential applications (Sect. 10). Often little variations in the powders and the processing parameters cause remarkable changes in the microstructure which have a pronounced effect on properties (Sects. 6 and 7). 

Omotowa BA, Phillips BS, Zabinski JS et al (2004) Phosphazene-based ionic liquids synthesis, temperature-dependent viscosity, and effect as additives in water lubrication of silicon nitride ceramics. Inorg Chem 43 5466-5471... 

OXYNITRIDE GLASSES EFFECTS OF COMPOSITION ON GLASS FORMATION AND PROPERTIES WITH IMPLICATIONS FOR HIGH TEMPERATURE BEHAVIOUR OF SILICON NITRIDE CERAMICS... 

H. Miyazaki, Y. Yoshizawa, K. Hirao. Effect of Crystallization of Intergranular Glassy Phases on the Dielectric Properties of Silicon Nitride Ceramics. Mater. Sci. Eng., 148.257-60 (2008). 

Bergs T (2002) Analyse der Wirkmechanismen beim laserunterstiitzten Drehen von Siliziumnitridkeramik [Analysis of the technical effect of laser-assisted turning of silicon-nitride ceramics]. Shaker, Aachen, in German... 

Effective machining of spheroidal irons with mixed microstructures can be performed using coated silicon nitride ceramic and CBN tools. This is due to the fact that these cutting tool materials guarantee acceptable tool life at reasonably high cutting speeds up to 400 m/min. 

Figure 12.9 Strength test results of a silicon nitride ceramic. Shown are data from uniaxial and biaxial strength tests. To determine the equivalent stress, the PIA criterion was used. Plotted in log-log scale is the characteristic strength of sets of specimens versus their effective volume. The solid line indicates the...

PSZs without pendent carbon bearing groups, which are precursors to silicon nitride ceramics, can be obtained by ammonolysis of dichlorosilane, H2SiCl2, or a stable complex, with a tertiary amine [18]. A stable H2SiCl2/2-pyridine complex has been used to produce Si-N fibers (Equations 5a, 5b). Pyridine acts as a catalyst in the condensation/crosslinking reaction, whereas other solvents, such as xylene, have the reverse effect [4-5]. The end product Is a clear solution of perhydropolysilazane (PHPSZ). 

Q. Wei, et al., "Microstructural Changes Due to Heat-Treatment of Annealing and Their Effect on the Creep Behavior of Self-Reinforced Silicon Nitride Ceramics", A/a/. Sci. and Eng., A299,141-151 poi)... 

Because Si,N ceramics are partially translucent to light and the strength limiting flaws are normally within a shallow depth under fte sur ce, optical methods are effective to detect and characterize these types of subsurface flaws. Argonne National Laboratory (ANL) has developed and utilized several optical methods for nondestructive evaluation (NDE) of subsurface flaws in silicon nitride ceramics. In this study, three optical methods are presented and evaluated (1) laser backscatter, (2) optical coherence tomography (OCT) and, (3) confocal microscopy. The la.ser backscatter is a two-dimensional method while both (XT and confocal are three-dimensional methods. It is demonstrated in the following that subsurface flaws of various types, sizes, and depths can be identified and imaged by these NDE methods. 

W. Zdaniewski, D. P. H. Hasselman, H. Knoch, and J. Heinrich. "Effect of oxidation on the thermal diffusivity of reaction-sintered silicon nitride," Ceramic Bulletin, 58(5), 539-540, 1979. 

D. R. Clarke, A Large Scale Processing Inhomogeneity in Silicon Nitride Ceramics and Its Effect on Oxidation, Materials Science Forum, 47 (Trans Tech. Publ., Switzerland, 1989), pp. 110 118. 

To examine the effects that might be achieved in the ceramic by simply altering the viscosity of the IGF, a brick wall type model can be used to characterize the effective viscosity of the silicon nitride ceramic composed of rigid, non-deforming grains surrounded by a viscous media. For the simple case of an array of cubic rigid grains with a size of G with an amorphous film of a thickness (t) and a viscosity (t o), the effective viscosity (rjeff) of the silicon nitride ceramic is ... 

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... 

Russell, L.M., Donaldson, K.Y., Hasselman, D.P.H., Corbin, N.D. Petrovic, J.J. and Rhodes, J.F. Effect of vapor-liquid-solid and vapor-solid silicon carbide whiskers on the effective thermal diffusivity/conductivity of silicon nitride matrix composites , J. Am. Ceram. Soc., 74[4] (1991) 874-877. 

Yaroshenko, V., Gogotsi, Y., Osipova, I., Effect of TiN addition on properties of silicon nitride based ceramics, in Ceramic Today - Tomorrow s Ceramics, ed. P. Vincenzini, Elsevier, Amsterdam, 2821-2830, 1991. 

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