PHYSICOCHEMICAL CHARACTERISTICS, PRODUCTION AND APPLICATION OF BORON-BEARING COMPLEX FERROALLOYS

The data on the feasibility of production and application of  complex ferroalloys from the standpoint of manufacturing technology, the used raw materials and the interaction with the steel are  provided. The production need of complex ferroalloys has been validated; the main principles of determination of ferroalloys chemical  composition are shown. The rational composition of complex fer-roalloys (ferro silicon manganese with boron, ferrosilicon with boron,  ferrosilicon manganese with boron and chrome) has been determined  based on the research of their physicochemical properties and their  specific interaction with basic melt. The comparison of characteristics of complex boron-bearing ferroalloys (melting temperatures,  density, melting time of ferroalloys in melt, etc.) was made against  the most used ferroboron and their advantages were shown. It was  noted that the complex boron-bearing ferroalloys must have active  element (Si, Al, Ti), because they promote binding oxygen and nitrogen from steel melt in firm compounds, and the compounds prevent  interaction of active element with boron. The boron concentration  in ferroalloy must be 0.7–2.0  %, because it increases the volume of  complex boron-bearing ferroalloy as consequence increase of reliability and stability of boron absorption. The study of oxidation of  boron-bearing ferroalloy has shown that ferrosilicon with boron are  far less oxidative (4–7 times) at higher temperatures (1430–1570  °С)  than ferroboron. The results have been given for manufacturing and  application of boron ferrosilicon in steel production. The recovery  rate of boron has been studied. The usage of ferrosilicon with boron  provided high recovery rate of boron in range of 77.8–96.3  % (average 86.6  %), without changes in present techno logy of steel deoxidation with ferrosilicon. The concentration of boron in metal at ladle  treatment is 0.0021–0.0027  % and the concentration of boron is not  less than 0.0020  % at casting. It was found that the entering of boron  with the help of ferrosilicon manganese with boron provides increase  of recovery rate of boron in 1,6 times (in average from 48 to 77  %)  relative to ferroboron usage.

1. Zhuchkov  V.I.,  Mal’tsev  Yu.B.  Physicochemical  characteristics  of new complex ferroalloys. In: Sb. trudov: Fizicheskaya khimiya i tekhnologiya v metallurgii  [Physical  chemistry  and  technology  in  metallurgy].  Ekaterinburg:  UrO  RAN,  1996,  pp.  131–144.  (In  Russ.).

2. Zhuchkov  V.I.,  Selivanov  E.N.,  Sychev A.V.,  Zayakin  O.V.,  Babenko A.A. Complex ferroalloys with boron for steel microalloying.  In: Sb. trudov mezhdunar. konf. “Fiziko¬khimicheskie osnovy met-allurgicheskikh protsessov”  [Proceedings  of  International  Conference “Physicochemical base of metallurgical processes”]. Moscow:  IMET RAN, 2012, p. 62. (In Russ.).

3. Parfenov A.A., Topil’skii A.V., Druinskii M.I. Suspension casting  of  FeSi-45.  In:  Sb:  Tekhnicheskii progress elektrometallurgii ferrosplavov[Technological development of ferroalloys electrometallurgy]. Dnepropetrovsk: TsBTI MChM USSR, 1975, pp. 179–181.  (In Russ.).

4. Manashev  I.R.,  Shatokhin  I.N.,  Ziatdinov  M.Kh.,  Bigeev  V.A.  Micro alloying  of  steel  with  boron  and  the  development  of  ferrotitanium  boride.  Steel in Translation.  2009,  vol.  39,  no.  10,   pp. 896–900.

5. Heckmann C. J., Ormston D., Grimpe F. Development of low carbon  Nb-Ti-B  microalloyed  steels  for  high  strength  large  diameter  linepipe.  Ironmaking and Steel¬making.  2005,  vol.  32,  no.  4,  pp.  337–371.

6. Upadhyaya N., Pujara M.G., Sakthivelb T., Mallikaa C., Lahab K.,  Kamachi Mudalia U. Effect of addition of boron and nitrogen on the  corrosion  resistance  of  modified  9Cr-1Mo  ferritic  steel.  Procedia Engineering. 2014, no. 86, pp. 606–614. 

7. Zhang Ya-long, Zhang Ying-yi1, Yang Fei-hua, Zhang Zuo-tai. Effect of alloying elements (Sb, B) on recrystallization and oxidation  of Mn-containing IF steel. Journal of iron and steel research, international. 2013, no. 3, vol. 20, pp. 39–44.

8. Kyung Chul Choa, Dong Jun Munb, Yang Mo Koob, Jae Sang Leeb.  Effect of niobium and titanium addition on the hot ductility of boron containing steel. Materials Science and Engineering A. 2011,  vol.  528, pp. 3556–3561.

9. Loґpez-Chipresa E., Mejıґa I., Maldonado C., Bedolla-Jacuinde A.,  El-Wahabi M., Cabrera J.M. Hot flow behavior of boron microalloyed steels. Materials Science and Engineering A. 2008, vol. 480,  pp. 49–55.

10. Stumpf W., Banks K. The hot working characteristics of boron bearing and conventional low carbon steel. Materials Science and Engineering A. 2006, vol. 418. pp. 86–94.

11. Fujishizo T., Haza T., Tezada E. etc. Application of B¬added low carbon bainite steels to wall x80 line pipe ultralow temperature use.  Dzaizo to Prosesu: CAMP JSJJ. 2009, 22, p. 640.

12. Ovchinnikov  D.V.,  Sofrygina  O.A.,  Zhukova  S.Yu.,  Pyshmintsev  I. Yu., Bityukov S.M. Influence of microalloying with boron on the structure and properties of high-strength oil pipe. Steel in Translation. 2011, vol. 41, no. 4, pp. 356–360.

13. Bigeev A.M.,  Bigeev  V.A.  Metallurgiya stali [Steel  metallurgy].  Magnitogorsk: MGTU, 2000, 544 p. (In Russ.).

14. Golubtsov V.A.  Teoriya i praktika vvedeniya dobavok v stal’ vne pechi[Theory and practice of addition in steel out of furnace]. Chelyabinsk: 2006, 421 p. (In Russ.).

15. Pilyushchenko V.L., Vikhlevchuk V.A., Pozhivanov M.A., Leporskii  S.V.  Nauchnye i tekhnologicheskie osnovy mikrolegirovaniya stali [Science and technology basis on microalloying steel]. Mos-cow: Metallurgiya, 1994, 384 p. (In Russ.).

16. Lukin S.V, Zhuchkov V.I., Vatolin N.A. The surface tension, density  and oxidation kinetic of Fe-Si-B alloys. Journal of the Less¬Common Metals. 1979, vol. 67, pp. 399–405.

17. Kim A.S, Zayakin O.V., Akberdin A.A., Kontsevoi Yu.V. Production and usage of new complex boron-bearing ferroalloys. Elektrometallurgiya, 2009, no. 12, pp. 21–24. (In Russ.).

18. Zhuchkov V.I., Andreev N.A. Development of new ferroalloys with  chromium. Proceeding of the XIV INFACON. Ukraine, Kiev, May 31 – June 4, 2015. Vol. II. pp. 407–413.

19. Potapov A.I., Semin A.E. Technological features of steel alloying  with  boron.  Izvestiya VUZov. Chernaya metallurgiya = Izvestiya. Ferrous Metallurgy. 2012, no. 9, pp. 68-69. (In Russ.).

20. Sirotin D.V. Effektivnost’ povysheniya kachestva stali za schet mikrolegirovaniya[Efficiency of quality improvement due to microalloyng]. Ekaterinburg: Institut ekonomiki UrO RAN, 2013, 50 p. (In  Russ.).