Warm/cold rolling processes for producing Fe-6.5wt% Si electrical steel with columnar grains

Abstract

A new technical prototype for producing Fe-6.5wt% Si electrical steel sheets by directional solidification, heat treatment before rolling, warm rolling, and cold rolling was proposed in the present study. The formability of Fe-6.5wt% Si electrical steel before rolling and the reasonable process parameters of this technical prototype were obtained. Experimental results reveal that the formability of Fe-6.5wt% Si electrical steel is improved significantly under the combination of directional solidification and heat treatment before rolling. Fe-6.5wt% Si electrical steel sheets with the thickness of 0.15 mm, bright surface, few edge cracks, and high rolling yield can be successfully fabricated using this technology without any intermediate annealing during the whole rolling. The combination of directional solidification, heat treatment before rolling, warm rolling, and cold rolling can work as a new process for highly efficient and compact fabrication of Fe-6.5wt% Si electrical steel sheets.

Keywords

silicon steel / deformation / rolling / mechanical properties / plasticity

References

[1] Tanaka Y, Takada Y, Abe M, Masuda S. Magnetic properties of 6.5% Si-Fe sheet and its applications. J. Magn. Magn. Mater., 1990, 83, 375.

[2] Komatsubara M, Sadahiro K, Kondo O, Takamiya T, Honda A. Newly developed electrical steel for highfrequency use. J. Magn. Magn. Mater., 2002, 242–245, 212.

[3] He ZZ. Electrical Steels, 1997, Beijing, Metallurgical Industry Press, 29.

[4] Zbroszczyk J, Ciurzyńska WH, Tanaka Y, Enokizono M, Olszewski J, Hasiak M. Microstructure and some magnetic properties of high-silicon Fe-Si sheets. J. Magn. Magn. Mater., 1996, 160, 141.

[5] Phway TPP, Moses AJ. Magnetostriction trend of non-oriented 6.5% Si-Fe. J. Magn. Magn. Mater., 2008, 320, e611.

[6] Bolfarini C, Silva MCA, Jorge AM Jr Kiminami CS, Botta WJ. Magnetic properties of spray-formed Fe-6.5%Si and Fe-6.5%Si-1.0%Al after rolling and heat treatment. J. Magn. Magn. Mater., 2008, 320, e653.

[7] Tian GK, Bi XF. Study on the Si penetration into Fe sheets using PVD method and its application in the fabrication of Fe-6.5wt.% Si alloys. Surf. Coat. Technol., 2010, 204, 1295.

[8] Varga LK, Mazaleyrat F, Kovac J, Kákay A. Magnetic properties of rapidly quenched Fe_100−xSi_x (15< x <34) alloys. Mater. Sci. Eng. A, 2001, 304–306, 946.

[9] Yuan WJ, Li JG, Shen Q, Zhang LM. A study on magnetic properties of high Si steel obtained through powder rolling processing. J. Magn. Magn. Mater., 2008, 320, 76.

[10] Okada K, Yamaji T, Kasai K. Basic investigation of CVD method for manufacturing 6.5%Si steel sheet. ISIJ Int., 1996, 36, 706.

[11] Yamaji T, Abe M, Takada Y, Okada K, Hiratani T. Magnetic properties and workability of 6.5% silicon steel sheet manufactured in continuous CVD siliconizing line. J. Magn. Magn. Mater., 1994, 133, 187.

[12] Liang YF, Ye F, Lin JP, Wang YL, Chen GL. Effect of annealing temperature on magnetic properties of cold rolled high silicon steel thin sheet. J. Alloys Compd., 2010, 491, 268.

[13] Liang YF, Lin JP, Ye F, Li YJ, Wang YL, Chen GL. Microstructure and mechanical properties of rapidly quenched Fe-6.5wt.% Si alloy. J. Alloys Compd., 2010, 504(Suppl.1): S476.

[14] Fang XS, Liang YF, Ye F, Lin JP. Cold rolled Fe-6.5wt.% Si alloy foils with high magnetic induction. J. Appl. Phys., 2012, 111, art. No. 094913.

[15] Xie JX, Fu HD, Zhang ZH, Jiang YB. Deformation twinning feature and its effects on significant enhancement of tensile ductility in columnar-grained Fe-6.5wt.%Si alloy at intermediate temperatures. Intermetallics, 2012, 23, 20.

[16] Fu HD, Yang Q, Zhang ZH, Xie JX. Effects of precipitated phase and order degree on bending properties of an Fe-6.5wt%Si alloy with columnar grains. J. Mater. Res., 2011, 26, 1711.

[17] Zhang ZH, Wang WP, Fu HD, Xie JX. Effect of quench cooling rate on residual stress, microstructure and mechanical property of an Fe-6.5Si alloy. Mater. Sci. Eng. A, 2011, 530, 519.

[18] Fu HD, Zhang ZH, Yang Q, Xie JX. Strainsoftening behavior of an Fe-6.5wt%Si alloy during warm deformation and its applications. Mater. Sci. Eng. A, 2011, 528, 1391.

[19] Shin JS, Bae JS, Kim HJ, Lee HM, Lee TD, Lavernia EJ, Lee ZH. Ordering-disordering phenomena and micro-hardness characteristics of B2 phase in Fe-(5-6.5%)Si alloys. Mater. Sci. Eng. A, 2005, 407, 282.