Saint-Petersburg State PolytechnicaL University, Chair of Metallurgical Technologies (Saint-Petersburg, Russia):

Konevskiy M. R., Dr. Eng., Prof.
Ryaboshuk S. V., Assistant

“Kramds-Kvartsit” company (Almaty, Kazakhstan):
Mukhambedyarov E. T., Dep. Production Director

E-mail (common): chemmet2008@yandex.ru

Increase of production volume and dimension range of phosphorus alloyed steels is accompanied with rise of quality requirements of phosphorous ferroalloys for alloying. At the same time, termination of the specialized production of phosphorous ferroalloys (ferro-phosphorus and ferro-manganophosphorus) in blast-furnaces led to necessity of their replacement by electrothermic ferro-phosphorus in steelmaking and foundry processes. This ferroalloy is a byproduct of phosphorus production process, where the main technological goal is obtaining of a chemical product, not alloying ferroalloy. The main reasons and ways to solve the problem of chemical instability of electrothermal ferrophosphorus are described in present paper. It is shown that unlike specialized production with permanent control and varying of metal chemical composition during thermal process, dimension range of accompanied products is forming via their separate grade-by-grade storage of the parts diff erent in their chemical composition. Such storage makes diffi culties for the production process. It is recommended to use FFE25-1 (ФФЭ25-1) grade during alloying of phosphorous steels, to lower the hazard of exceeding the preset phosphorous limits. It is also expedient to introduce the corresponding corrections and additions in the technological manuals for melting of phosphorous steels and in the technical specifi cation for eletrothermal ferrophosphorous.

1. Ershov V. A., Pimenov S. D. Elektrotermiya Fosfora (Electrochemistry of phosphorus). Moscow : Khimiya, 1996. 248 p.
2. Gasik M. I., Lyakishev N. P., Emlin B. I. Teoriya i tekhnologiya proizvodstva ferrosplavov (Theory and technology of ferroalloys manufacturing). Moscow : Metallurgiya, 1988. 783 p.
3. Zagyanskiy A. P. Doklady Akademii Nauk SSSR — Reports of USSR Academy of Sciences. 1953. Vol. ХС1, No. 6. pp. 1369–1372.
4. Molchanov V. I. Stal — Steel in Translation. 1947. No. 4. pp. 295.
5. Konevskiy M. R., Mukhambedyarov E. T., Ryaboshuk S. V. Issledovanie vzaimodeystviya komponentov v sisteme Me_xO_y–Ca₃P₂O₈–C. Aktualnye problemy rudnoy i khimicheskoy elektrotermii. Sbornik trudov Vserossiyskoy nauchno-tekhnicheskoy konferentsii (Research of interaction of components in the Me_xO_y–Ca₃P₂O₈–C system. Urgent problems of ore and chemical electrothermy. Collection of papers of All-Russian scientific and technical conference). Saint Petersburg, 2012. pp. 163–167.
6. Dragomir G. Properties of Liquids. Proceedings of the 2^nd International conference. Tokyo, 1972. London, 1973. pp. 502–512.
7. Konevskiy M. R. Izvestiya Akademii Nauk SSSR. Metally — Bulletin of USSR Academy of Sciences. Metals. Moscow, 1982. pp. 18–21.
8. Streltsov A. N., Ershov V. A. Sposob vyplavki fosforistykh spokoynykh staley (Method of smelting of phosphorous killed steels). Certificate of Authority No. 208742. Bulletin of Inventions No. 4, 1968.