Sialons are modern technical ceramics based on silicon nitride (Si3N4). Although they maintain the excellent toughness properties and thermodynamic stability of silicon nitride with their isostructural composition, they feature larger cell dimensions for the formation of high-density refractory components.
This exceptional molecular density allows excellent resistance to extreme mechanical degradation and corrosion, which are very usual in industrial manufacturing environments. Hence, Sialons are continuously employed for the fabrication of wear components and thermally stable barriers for heat-sensitive elements. Commonly, the materials of the sialon group are used for producing grinding media, cutting tools, and thermocouple protection sheaths.
Syalon 050 is distinct from other sialons due to its enhanced hardness and high temperature properties. Although all sialons exhibit excellent mechanical stability when common industrial corrosive elements such as alkalis and acids are present, Syalon 050 was particularly intended to withstand the most difficult wear conditions. It is stable in the presence of molten aluminium for prolonged periods of exposure and is completely non-reactive to most industrial acids and alkalis at boiling temperatures.
In this article, the capacities and applications of Syalon 050 are explored in more detail.
Specialized Corrosion-Resistant Sialons
Syalon 050 is an α/β-sialon composite. Its fully dense microstructure contains both interlocking needle-like β-SiAlON grains and a fine equiaxed α-SiAlON grains. The material’s hardness rating of 94 HRA comes from this structural matrix, forming a 0% porosity bulk material with a very low glassy-phase content that is intrinsically resistant to a range of industrial corrosives and refractory temperatures. It has the ability to maintain this mechanical stability at continuous operating temperatures up to 1450 °C (2552 °F), demonstrating total non-reactivity with molten aluminium, tin, and brass for metallurgical applications.
Sialons for Chemical Processing
Sialons are continuously used for enhancing transport processes and chemical handling in industrial chemical manufacturing and production facilities. Tubes produced from Syalon 050 do not react with common acids and alkalis such as hydrofluoric acid, potassium chloride, and acetic acid. These have been examined at 100% concentration and boiling temperatures for nearly 100 hours of continuous exposure.
Sialons for Metering Valves
A metering valve is an important component in the oil and gas sector and is used for controlling the flow rates of corrosive materials over transport components. Syalon 050 is the preferred sialon ceramic for fabricating exceptionally tough metering valves for marine and chemical applications, offering reliability and security, and surpassing traditional metering valve materials by factors of up to 14 to 1.
Sialons for Shot-Blast Nozzles
Shot-blast nozzles are the outlet component for industrial hot blasting surface preparation. They have the ability to withstand huge abrasive pressures and velocities throughout their service application in automotive manufacturing, construction, and wear industries. These sectors employ different abrasive methodologies, from wet abrasive blasting to hydro-blasting. Sandblasting is the most conventional technique, which involves projecting a continuous, pressurized stream of abrasive grit over a surface to modify its composition.
The challenging specifications of hot-blasting equipment need high-performance materials with the ability to resist sustained temperatures and pressures. It is common to use traditional metals with excellent hardness values for preparing tough shot-blast nozzle linings; however, they lack the ability to compete with the distinctive mechanical stability of advanced silicon nitride ceramics.
Syalon 050 was customized for wear applications, where components are required to continually withstand various abrasive and corrosive elements. Shot-blast nozzles are subject to normal abrasion from heavily pressurized and high-temperature media. Silicon nitride shot-blast nozzles were intended to surpass standard industry materials like tungsten carbide (WC) and alumina (Al2O3), by offering advanced temperature resistances of up to 1450 °C (2642 °F) at pressures of up to 100 psi for tough continuous operating hours.
This information has been sourced, reviewed and adapted from materials provided by International Syalons.
For more information on this source, please visit International Syalons.