The different Syalon forms

Syalons/Sialons are alloys, based on silicon nitride as the solvent. Because beta-Syalon has the same atomical arrangement, its mechanical and physical properties are almost similar to those of silicon nitride. Chemically, it has some of the features of alumina, Al2O3.

Our standard product range is based on beta silicon nitride. Clearly Syalons can also be made that are based on alpha silicon nitride and on oxynitride each of which has a different crystallographic structure. These different forms have traditionally been denoted by the notations alpha-prime, beta-prime or O-prime, also known as alpha-Sialon, beta-Syalon or O-Sialon.

O-Sialon is based on silicon oxynitride; it is not as strong or as hard as beta-Syalon. It is not cheaper than other SiN/Syalon/Sialon types unless it is produced by some novel processing techniques which are more and more common for the production of O-Sialon. Such techniques involve carbothermal reduction in which cheap raw materials such as coke and sand are converted to a Sialon by heating in nitrogen.

Usually our material is described as Syalon. Our material is a hundred percent beta-quality (no other, probably cheaper components are added). We fire our beta-Syalon at 2000° C (!) meanwhile most O-types are fired at 1200 – 1300° C. The higher temperature results into a material which is absolutely gastight with zero porosity.


SRS Amsterdam BV gibes a guarantee on Syalon protection tubes against manufacturing faults and chemical corrosion for 1 year in molten metal (aluminium) and 3 months when used in molten brass. For further details please download the PDF-file here under.



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