Fine Silicon Nitride Ceramic Products

Silicon nitride (SN) ceramics po.s.sess similar properties to silicon carbide ceramics and can be utilized in the same application sectors. 

Reaction of Si02-C-mixtures at temperatures of up to 1500°C in a nitrogen atmosphere  

Reaction of SiClq with ammonia in the liquid phase (e.g. in an organic solvent)  

All these processes produce mixtures of a- and P-S13N4 in varying proportions. 

Of these processes direct nitriding and the reaction of SiCl4 with NH3 are currently industrially operated. 

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Metallurgical grade silicon is marketed in a coarsely crushed form or as a finely ground powder in different particle sizes. Powders with increased purity due to acid washing, particularly for the removal of metallic impurities, are specialty products. They are utilized, for example, in the manufacture of silicon nitride powder or reaction-bonded silicon nitride ceramic components and are therefore the starting materials for engineering ceramic specialties. 

Pattimore J, Nishio A, Dewitte C, Unno Y, Masuda M (1997) Optimisation of Grinding for Cylindrical Silicon Nitride Components for Mass Production. In Niihara K, Hirano S, Kanzaki S, Komeya K, Moriuaga K (eds) Ceramic Materials and Component for Engines. Japan Fine Ceramics Association, Tokyo, p 406... 

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