INFLUENCE OF HIGH-CARBON STEEL BILLET MOVEMENT SPEED IN PATENTENING UNIT ON STRUCTURE AND MECHANICAL PROPERTIES FORMATION

At present, intensive reinforced concrete constructions of various purposes have got considerable distribution, in which, as a rule, compressive stresses in concrete and stretching in the reinforcement are created. At the same time, the prestressed reinforcement better perceives the loads exerted on it by external forces during the whole lifetime of the construction, which allows increasing the load on the structure in comparison with the construction with non-tensioning reinforcement or at the same load value to reduce the dimensions of the construction and achieve savings in concrete and steel. One of the urgent problems of modern hardware production is considered to be development of the technology of nanostructured reinforcing ropes manufacturing, which are the main element of stressed reinforced concrete constructions for responsible use. The most important technological operation is patenting in which steel acquires the structure of a fine ferrite-carbide mixture (FCM), which has high strength and, at the same time, the deformation ability with large degrees of compression. The authors have investigated the effect of increasing speed of rod movement in the patenting unit on the structure and mechanical properties formation in steel of grades 80, 70 and 50 with the aim of determining the possibility to increase the productivity of the patenting unit without reducing the strength and plastic characteristics of steel in the production of nanostructured reinforcing ropes billets for reinforced concrete stressed constructions for responsible use. To determine temperature-time parameters of heat treatment, the isothermal diagram decomposition of the undercooled austenite was constructed using Gleeble 3500 research complex. A qualitative and quantitative analysis of the microstructure with the determination of the FCM interlamellar spacing was carried out at different speeds of the rod movement in the patenting unit. The mechanical properties under tension were tested. It was established that at all processing speeds, the values of the FCM interlamellar spacing in the range 0.1  –  0.2  μm are practically identical and optimal for the subsequent drawing. Due to the formation in the patenting of the disperse structure of FCM, an increase in the strength of the billet is achieved, which, with subsequent drawing, can withstand large crimps without breakage. It is shown that in the production of patented nanostructured billets for reinforcing ropes, one can increase the speed in patenting unit to 5 m/min without reduction of strength and plastic characteristics of the billet.

1. Mikhailov  K.V.,  Volkov  Yu.S.  Rope  reinforcement  for  complex  structures made of prestressed concrete. Beton i zhelezobeton. 2009,  no. 2, pp. 25–28. (In Russ.). 

2. Kim K.W., Won J.H., Jung S.D., Park J.W., Kim M.K. Full-scaled  experiment  for  behavior  investigation  of  reinforced  concrete  columns with high-strength wire ropes as lateral spiral reinforcement.  In:  IT Convergence and Security.  Kuinam  J.  Kim,  Kyung-Yong  Chung eds. New York, London: Springer, 2012, pp. 1139–1146.

3. Vaghei R., Hejazi F., Taheri H., Jaafar M.S., Aziz F.N.A.A. Development of a new connection for precast concrete walls subjected to  cyclic loading. Earthquake Engineering and Engineering Vibration.  2017, vol. 16, no. 1, pp. 97–117. 

4. Proizvodstvo vysokoprochnoi stal’noi armatury dlya zhelezobetonnykh shpal novogo pokoleniya [Manufacturing of high-strength steel reinforcement for reinforced concrete sleepers of a new generation].  Chukin  M.V.  ed.  Moscow:  Metallurgizdat,  2014,  276  p.  (In Russ.). 

5. Bargujer S.S., Suri N.M., Belokar R.M. Pearlitic steel wire: High  carbon steel based natural nanomaterial by lead patenting process.  Materials Today: Prceedings. 2016, vol. 3, no. 6, pp. 1553–1562.

6. Сhukin M.V., Korchunov A.G., Gun G.S., Polyakova M.A., Koptseva N.V. Nanodimentional structural part formation in high carbon  steel by thermal and deformation process. Vestnik of Nosov Mag-nitogorsk State Technical University. 2013, no. 5 (45), pp. 33–36.

7. Potemkin  K.D.  Termicheskaya obrabotka i volochenie vysokoprochnoi provoloki  [Heat  treatment  and  drawing  of  high-strength  wire]. Moscow: Metallurgizdat, 1963, 120 p. (In Russ.).

8. Wiewiórowska S., Muskalski Z. The assessment of the structure and  properties of high-carbon steel wires after the process of patenting  with induction heating. Archives of metallurgy and materials. 2015,  vol. 60, no. 2, pp. 2015–2018.

9. Yukhvets  I.A.  Proizvodstvo vysokoprochnoi armatury [Manufacture of high-strength reinforcement]. Moscow: Metallurgiya, 1973,  264  p. (In Russ.).

10. Koptseva N.V., Chukin M.V., Efimova Yu.Yu., Trubitsyn G.V., Lit-vinova N.V. Features of high-carbon steels structure formation during patenting. Stal’. 2013, no. 2, pp. 42–45. (In Russ.).

11. Schastlivtsev V.M., Mirzaev D.A., Yakovleva I.L., Okishev K.Yu.,  Tabatchikova T.I., Khlebnikova Yu.V. Perlit v uglerodistykh stalyakh [Perlite in carbon steels]. Ekaterinburg: UrO RAN, 2006, 311 p. (In  Russ.).

12. Schastlivtsev V.M., Yakovleva I.L. Fine-lamellar pearlite: The first  bulk nanomaterial in carbon steel. Bulletin of the Russian Academy of Sciences: Physics. 2015, vol. 79, no. 9, pp. 1077–1080. 

13. Zhang X., Godfrey A., Huang X., Hansen N., Liu Q. Microstructure  and  strengthening  mechanisms  in  cold-drawn  pearlitic  steel  wire.  Acta Materialia. 2011, no. 59 (9), pp. 3422–3430.

14. Taleff E.M., Lewandowski J.J., Pourladian B. Microstructure-property relationships in pearlitic eutectoid and hypereutectoid carbon  steels. Journal of Materials. 2002, vol. 54 (7), pp. 25–30.

15. Lebedev V.N., Noskov S.E., Pudov E.A., Litvinova N.V., Gun G.S.,  Chukin V.V.  Unit  for  patenting  of  bars  used  for  reinforcement of  reinforced concrete sleepers of new-generation. Kuznechno-shtampovochnoe proizvodstvo. Obrabotka materialov davleniem.  2011,  no. 5, pp. 21–24. (In Russ.).

16. Lebedev V.N.,  Korchunov A.G.,  Chukin  M.V.  Production  of  stabilized  high-strength  reinforcement  steel  for  the  new  generation  of ferroconcrete railroad ties. Metallurgist. 2011, vol. 55, no. 1-2,  pp.  54-58.

17. Chukin M.V., Gun G.S., Korchunov A.G., Polyakova M.A. Prospects for production of high-strength steel reinforcement made of  high-carbon steel grades. Chernye metally. 2012, no. 12, pp. 8–16.  (In Russ.).

18. Lambert-Perlade A., Gourgues A.F., Pineau A. Austenite to bainite  phase transformation in the heat-affected zone of high strength low  alloy steel. Acta Mater. 2004, no. 8 (52), pp. 2337–2348.

19. Schastlivtsev  V.M.,  Yakovleva  I.L.,  Koptseva  N.V.,  Efimova  Yu.Yu., Nikitenko O.A. Patterns of structure formation under thermal deformations in the processes of production of high-strength  reinforcement. Vestnik Magnitogorskogo gosudarstvennogo tekhnicheskogo universiteta im. G.I. Nosova.  2014,  no.  1  (45),  pp.  32–37. (In Russ.).

20. Elwazri A.M., Wanjara P., Yue S. The effect of microstructural characteristics of pearlite on the mechanical properties of hypereutectoid. Materials Science and Engineering. 2005, A 404, pp. 91–98.

21. Borisenko A.Yu., Lutsenko V.A., Lutsenko O.V., Kurenkova T.P.,  Seregina E.S., Demidov A.V. Structure and properties of patented  high-carbon wire. Chernye metally. 2012, no. 10 (74), pp. 31–36.  (In Russ.).

22. Chukin D.M., Ishimov A.S., Zherebtsov M.S., Meshkova A.I. Using the Gleeble 3500 system to conduct dilatometric study of 80R  microalloyed  steel.  Obrabotka sploshnykh i sloistykh materialov.  2012, no. 38, pp. 148–155. (In Russ.).

23. Koptseva N.V., Chukin M.V., Nikitenko O.A. Use of the Thixomet  PRO software for quantitative analysis of the ultrafine-grain structure of low-and medium-carbon steels subjected to equal channel  angular pressing. Metal Science and Heat Treatment. 2012, vol. 54,  no. 7-8, pp. 387–392.