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95th anniversary of the Metal forming chair of the Ural federal university
Название Influence of properties anisotropy on stress-deformed state at rolling of stripes from electrical steel
Автор Yu. N. Loginov, M. P. Puzanov
Информация об авторе

Ural Federal University (Ekaterinburg, Russia):

Yu. N. Loginov, Dr. Eng., Prof, e-mail: j.n.loginov@urfu.ru
M. P. Puzanov, Post-graduate student

Реферат

The effect of the anisotropy of the properties on the stressstrain state during the rolling of a strip of electrical steel is investigated. Formulations of the defining relations for anisotropic materials were used, from which the need to measure the strength properties of the material in different directions followed. In the experimental part of the work, the electrical steel of industrial production of the following chemical composition was used to determine the anisotropy coefficients of the material, %: 0.03 C; 3.2 Si; 0.3 Mn; 0.01 Ni; 0.015 Al; 0.002 Cr; 0.55 Cu; 0.003 Ti; 0,01 N. The strip of the investigated steel was rolled in the cold state with an initial thickness of 2.50 mm to a final thickness of 0.70 mm in 4 passes with a total reduction of 72%. To calculate the coefficients of the Hill's plasticity equation, it is required to conduct the tests in the direction normal to the plane of the sheet, so the most suitable method for studying the mechanical properties of a thin sheet material is to measure the microhardness. From the cold-rolled sheet, flat samples measuring 0.70 × 10 × 20 mm with different orientations relative to the coordinate system of the rolling process were prepared. The tests were carried out on the Shimadzu HMV-G21DT unit by pressing a tetrahedral pyramid with a square base with the method of the reconstructed print. The value of the static load was 0.049 N. Based on the results of the statistical processing of the test results, the dependence of the average hardness of the cold-rolled electrical steel on the measurement direction was obtained. Using the known relationship between the conditional yield strength of the material and the hardness, the coefficients of the Hill's plasticity equation were established. In the theoretical part of the work, the finite element method was used to solve the boundary value problem of thin-film rolling for an isotropic and anisotropic medium with the assignment of the corresponding boundary conditions. The distribution of stresses and deformations in the rolled strip is given. Differences in the stress-strain state of the metal in the deformation zone are revealed. The longitudinal stresses for rolling an anisotropic strip were higher by 40%, and the stresses along the thickness of the rolled steel were lower by 13% than the corresponding parameters for rolling an isotropic strip.
The study was made with partial financial support of the Program 211 of the RF Government (agreement № 02.A03.21.0006).

Ключевые слова Thin-sheet rolling, anisotropy, electrical steel, stress, deformation, finite element method.
Библиографический список

1. Kazakov A. A., Kisilev D. V., Kazakova E. I., Kurochkina O. V., Khlusova E. I., Orlov V. V. Infl uence of structural anisotropy in ferrite-bainite tube strip steel after thermomechanical treatment on the level of their mechanical properties. Chernye Metally. 2010. No. 6. pp. 7–14.
2. Moy C. K. S. et al. Influence of heat treatment on the microstructure, texture and formability of 2024 aluminium alloy. Materials Science and Engineering: A. 2012. Vol. 552. pp. 48–60.
3. Elsner A., Kaspar R., Ponge D. Recrystallization texture of cold rolled and annealed IF steel produced from ferritic rolled hot strip. Materials Science Forum. 2004. Vol. 467–470, Iss. 1. pp. 257–262.
4. Chen Q, Pan Q., Wei L. Microstructures and properties of Al–Mg–Sc aluminum alloy sheet at diff erent orientations. Journal of Central South University (Science and Technology). 2013. Vol. 44, Iss. 3. pp. 921–929.
5. Shekhawat S. T. Magnetic properties in deformed grain oriented steel: on the role of strain hardening exponent and microstructural developments. ISIJ International. 2012. Vol. 52, Iss. 11. pp. 2100–2108.
6. Solovei V. D., Loginov Yu. N., Puzanov M. P. Evaluating the flow stress of electrical steel under cold rolling in terms of the strainrate hardening effect. AIP Conference Proceedings. 2016. Vol. 1785.
7. Kononov A. A., Zotov O. G., Shashurin A. I. Distribution of crystallographic orientations in an anisotropic electrical steel under rolling stages. Metal Science and Heat Treatment. 2014. Vol. 56, Iss. 7–8. pp. 49–53.
8. Candiotti M., di Schino G., Hartung H. G., Haentjes M., Püttgen W., Sasse S. Complex strip processing lines for grain-oriented electrical steel strip. Chernye Metally. 2011. No. 7-8. pp. 61–66.
9. Kustas A. B., Johnson D. R., Trumble K. P., Chandrasekar S. Enhancing workability in sheet production of high silicon content electrical steel through large shear deformation. Journal of Materials Processing Technology. 2018. Vol. 257. pp. 155–162.

10. Lobanov M. L., Redikultsev A. A., Kagan I. V., Pervushina O. V., Rusakov G. M. Effect of the grain orientation in the material used for the preparation of an ultrathin electrical steel on its texture and magnetic properties. The Physics of Metals and Metallography. 2011. Vol. 111, Iss. 5. pp. 479–486.
11. Loginov Y. N., Puzanov M. P. Finite element modeling of the upsetting of an anisotropic cylindrical workpiece. Proceedings of the 11th International Conference on Mechanics, Resource and Diagnostics of Materials and Structures. 2017. Vol. 1915. P. 040033.
12. Pisarenko G. S. Equations and boundary problems of the plasticity and creep theory. Reference book. Kiev: Naukova dumka, 1981. 496 p.
13. Bogatov А. А. Mechanical properties and models of metals destruction. Tutorial for higher education institutions. Yekaterinburg: GOU VPO UGTU-UPI, 2002. 329 p.
14. Finelli A., Labanti M. Analysis of the influence of the anisotropy induced by cold rolling on duplex and super-austenitic stainless steels. Frattura ed Integrità Strutturale. 2010. №. 13. pp. 24–30.
15. Tretyakov A. V., Zyuzin V. I. Mechanical properties of metals and alloys during forming: reference book. Moscow: Metallurgiya, 1973. 224 p.
16. Prates P. A., Oliveira M. C., Fernandes J. V. On the equivalence between sets of parameters of the yield criterion and the isotropic and kinematic hardening laws. Int. J. Mater. Form. 2015. Vol. 8, Iss. 4. pp. 505–515.
17. Eremin G. N., Molotilov B. V., Bakhtin S. V., Parakhin V. I. Current trends in the technology and technological methods for increasing quality of cold-rolled transformer steel. Proizvodstvo prokata. 2018. No. 2. pp. 7–14.

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