Microstructure and texture evolution of nonoriented silicon steel during the punching process

Abstract

The iron core of a motor is mainly manufactured from rolled nonoriented silicon steel using a punching process that leads to deformation and texture evolution at the cutting edge. According to this process, circular samples of nonoriented silicon steel were prepared by punching using blunt punch tools. In this work, two positions along the rolling and transverse directions at the cutting edge were analyzed. The main mechanisms of deformation for both positions are dislocation slip and formation of shear bands. These two mechanisms lead to similar texture evolutions for both positions. The dislocation slip leads to the formation of the {221} 〈uvw〉 component in the unbending area (200 µm away from the cutting edge) and intermediate continuum-bent area. Additionally, the evolution of the texture from the {111} γ fiber to the {110} fiber was observed at the extremity of the cutting edge with the formation of shear bands.

Keywords

microstructure / texture / nonoriented silicon steel / punching

References

[1] Honda K, Kaya S. On magnetization of single crystals of iron. Sci. Rep. Tohoku Imp. Univ., 1926, 15, 721

[2] Liu HT, Liu ZY, Li CG, Cao GM, Wang GD. Solidification structure and crystallographic texture of strip casting 3 wt.% Si non-oriented silicon steel. Mater. Charact., 2011, 62(5): 463.

[3] Xu YB, Zhang YX, Wang Y, et al. Evolution of cube texture in strip-cast non-oriented silicon steels. Scripta Mater., 2014, 87, 17.

[4] Mehdi M, He YL, Hilinski EJ, Edrisy A. Effect of skin pass rolling reduction rate on the texture evolution of a non-oriented electrical steel after inclined cold rolling. J. Magn. Magn. Mater., 2017, 429, 148.

[5] Sanjari M, He YL, Hilinski EJ, Yue S, Kestens LAI. Texture evolution during skew cold rolling and annealing of a non-oriented electrical steel containing 0.9wt% silicon. J. Mater. Sci., 2017, 52(6): 3281.

[6] Mehdi M, He YL, Hilinski EJ, Kestens LAI, Edrisy A. The evolution of cube ({001}<100>) texture in non-oriented electrical steel. Acta Mater., 2020, 185, 540.

[7] Jiao HT, Xu YB, Xu HJ, et al. Influence of hot deformation on texture and magnetic properties of strip cast non-oriented electrical steel. J. Magn. Magn. Mater., 2018, 462, 205.

[8] Li HZ, Liu HT, Liu ZY, Lu HH, Song HY, Wang GD. Characterization of microstructure, texture and magnetic properties in twin-roll casting high silicon non-oriented electrical steel. Mater. Charact., 2014, 88, 1.

[9] Liu HT, Liu ZY, Sun Y, et al. Formation of {001}<510> re-crystallization texture and magnetic property in strip casting non-oriented electrical steel. Mater. Lett., 2012, 81, 65.

[10] Sha YH, Sun C, Zhang F, et al. Strong cube recrystallization texture in silicon steel by twin-roll casting process. Acta Mater., 2014, 76, 106.

[11] Zhang N, Yang P, Mao WM. Through process texture evolution of new thin-gauge non-oriented electrical steels with high permeability. J. Magn. Magn. Mater., 2016, 397, 125.

[12] Sahoo G, Singh CD, Deepa M, Dhua SK, Saxena A. Recrystallization behaviour and texture of non-oriented electrical steels. Mater. Sci. Eng. A, 2018, 734, 229.

[13] F. Ossart, E. Hug, O. Hubert, C. Buvat and R. Billardon, Effect of punching on electrical steels: Experimental and numerical magneto-mechanical analyses, [in] the 2000 IEEE International Magnetics Conference (INTERMAG), Toronto, ON, 2000.

[14] Weiss HA, Leuning N, Steentjes S, et al. Influence of shear cutting parameters on the electromagnetic properties of non-oriented electrical steel sheets. J. Magn. Magn. Mater., 2017, 421, 250.

[15] Saleem A, Goldbaum D, Brodusch N, Gauvin R, Chromik RR. Microstructure and mechanical property connections for a punched non-oriented electrical steel lamination. Mater. Sci. Eng. A, 2018, 725, 456.

[16] Baudin T, Penelle R. Determination of the total texture function from individual orientation measurements by electron backscattering pattern. Metall. Mater. Trans. A, 1993, 24(10): 2299.

[17] Field DP, Bradford LT, Nowell MM, Lillo TM. The role of annealing twins during recrystallization of Cu. Acta Mater., 2007, 55(12): 4233.

[18] Mackenzie JK. Second paper on statistics associated with the random disorientation of cubes. Biometrika, 1958, 45(1–2): 229.

[19] Mason JK, Schuh CA. The generalized Mackenzie distribution: Disorientation angle distributions for arbitrary textures. Acta Mater., 2009, 57(14): 4186.

[20] Jin X, Fu BQ, Zhang CL, Liu W. Evolution of the texture and mechanical properties of 2060 alloy during bending. Int. J. Miner. Metall. Mater., 2015, 22(9): 966.

[21] T. Nguyen-Minh, J.J. Sidor, R.H. Petrov, and L.A.I. Kestens, Shear banding and its contribution to texture evolution in rotated Goss orientations of BCC structured materials, IOP Conf. Ser.: Mater. Sci. Eng., 82(2015), art. No. 012023.

[22] Dorner D, Zaefferer S. Microstructure and texture of shear bands in cold rolled silicon steel single crystals of Goss orientation. Solid State Phenom., 2005, 105, 239.