Plasma technology of inorganic compounds
Since the mid 1960s the Latvian Institute of Inorganic Chemistry of the Latvian Academy of Sciences has been carrying out an extensive research in the field of plasma chemistry and plasma technology. Research results gave an opportunity to work out a range of new technological methods for the production of different hard-to-melt compounds (nitride, carbide, boride, oxide, carbonitride and their compositions) in the form of ultra fine powders with the size of separate particles being smaller than 100 nm. Comprehensive investigation of nanosize powders produced in this way made it possible to create materials and coatings characterized by very high maintenance qualities (hardness, mechanical strength, chemical, thermal and wear resistance, specific electrophysical and optical qualities etc.)
The developed technology differs from the traditional ones by the fact that the compound synthesis proceeds from the molecular, atomar or ione state of the substance and the condensed phase forming in a very short while at a very high temperature. Thus particles of a very small size and specific properties are formed.
From 1971 to 1990 the Institute of Inorganic Chemistry was the leading organization in USSR co-ordinating research on the synthesis of hard-to-melt compounds in plasma.
The technology is used in:
Implementation of technological methods:
In 1976 the Institute of Inorganic Chemistry formed a Special Design Office of Inorganic Materials with several technological branches providing the production of 3-5 tons of powder a year. Several production enterprises utilizing the plasma technology were later formed also in Russia and Ukraine. In Latvia this technology now is used by "Plasma & Ceramic Technologies" Ltd. and "Neomat" Ltd. In the 80-ties the technology of plasma coating production was used in 14 plants and production departments under methodical guidance of the above-mentioned Special Design Office. Some of them still continue their work today. The biggest amount of work in this field is carried out by the individual enterprise "Terpa" that was formed on the basis of the correspondent department of the Design Office. Materials and products on the basis of ultra fine powders were produced by several organizations in Oblinsk, Leningrad, Noginsk, Kiev, Karsnojarsk, Jakutsk, Kaliningrad, Omsk, Moscow, Podolsk, Zaporozye etc. In Latvia this work is carried on by "Plasma & Ceramic Technology" Ltd. in co-operation with several institutes and companies in Germany, France etc.
About 90 authors' certificates of USSR and 3 foreign patents have been received.
V.Petrunicus, V.Mihailovs, J.Korolova, J.Grabis, T.Millers, G.Heidemane, J.Zalite, V.Troickis, S.Panfilovs, J.Cvetkovs, O.Grebcova, J.Kijanskis, L.Stafeckis, A.Uelskis. Plasmochemical method for the production of fine powders.
Patent of Germany DE Nr. 333940.
The invention is registered also in France (patent B1 Nr.8318307, 1987) and Hungary.