Interdepartmental laboratory of advanced technologies for creation of new materials has been working on getting composite ceramics on the basis of sialons by spark-plasma sintering and the research of their structure and characteristics.

Sialon is a promising material which can function in extreme conditions and is free-cutting by traditional instruments. Possessing high strength, chemical stability and thermal resistance, sialon-based materials are used at high-speed mechanical load, heat pulse, impact of aggressive chemical agents and abrasion particles. Depending on the additive sialon-based materials are widely used not only as high-temperature construction ceramics (cutting tools) but also as functional materials (phosphor in white light-emitting diodes).

For the production of solid composite sialon-based ceramics a wide range of powder material consolidation methods is used. Nowadays the quickest and the most effective method of thickening of ceramics and other solid materials is the method of spark-plasma sintering. This technology allows getting materials with density close to theoretical value and the size of grains close to the size of the starting powder.

The method is the combined action of average mechanical pressure and electric current. Heating of current-conducting mould up to sintering temperature is made through pulse advancing of direct current. Usage of large currents and short impulses of 10^-3 duration allows heating at high speed (up to 500°С/min) shortening the duration of sintering process and limiting the growth of powder particles.

Below: the developer of sialon ceramics, engineer of Interdepartmental laboratory of advanced technologies for creation of new materials Evgeniya Nefedova