Scientists from TSC SB RAS have proposed a cost-effective method to produce sialon


A team of scientists from the Laboratory of New Metallurgical Processes (Tomsk Scientific Center of the SB RAS) led by Konstantin Bolgaru developed a cost-effective method to produce expensive sialon. This resistant and refractory industrial material has been proposed to be produced from cheap raw materials, such as ferroalloy production wastes. These results are reported in the highly ranked journal Ceramics International .



On average, the price of one kilogram of sialon is now several tens of thousands of rubles. The high cost of this material is due to the high cost of raw materials and complex production technology. But even this fact does not affect its demand in the world. Researchers from the TSC SB RAS propose a new approach that allows the cost of sialon to be reduced by several times. This can be achieved through the use of cheap raw materials and an energy-efficient production method. Briefly, the technology can be described as follows: first, nitriding in combustion mode, then removing unnecessary components.


First, cheap ferroalloy production wastes that contain iron and nitride-forming elements necessary to produce sialon are used as raw materials, says junior researcher Anton Reger. Then the reaction of self-propagating high-temperature synthesis (SHS) takes place, which is one of the most energy-efficient and cost-effective ways to produce various materials. Many works were done for this purpose, including careful preparation of raw materials and selection of optimal synthesis conditions.


It took hundreds of experiments to find the conditions to produce sialon. To initiate such a reaction, it is necessary to consider many parameters, such as pressure, temperature, diameter, structure of the raw material, and much more.


Another difficulty was that the SHS process cannot be controlled due to its fast velocity: the duration of such a chemical combustion reaction is only a few seconds, explains Konstantin Bolgaru, head of the Laboratory of New Metallurgical Processes (TSC SB RAS). After SHS synthesis is completed, it is necessary to purify (wash) the synthesized material from iron impurities. The result is a valuable, expensive product pure nanopowder.


Scientists plan to develop the promising topic in two directions: to improve the technology and increase the volume of the synthesized material for use in industry, as well as to conduct basic research on adding various additives, including rare-earth elements, to the structure of sialon in order to obtain materials with new properties.