Method for preparing tropism silicon steel

Abstract

The invention discloses a manufacture method of an oriented silicon steel, which adopts smelting, continuous casting, heating, rough rolling, finish rolling, normalizing, cold rolling and heat treatment processes. The method is characterized in that continuous bending, continuous straightening, low-head vertical-bending medium-thin slab caster is adopted, the tundish superheat is 15 to 45 DEG C, the drawing speed is 2 to 4 m/min, the temperature gradient of a cast strand is 80 to 200 DEG C/mm, the surface temperature is 850 to 1,150 DEG C, the slab thickness is 100 to 170 mm, the surface charging temperature of a section cast strand and a continuous cast strand is not less than 800 DEG C, and the heating speed is larger than 5 DEG C/min; and a hot coil box is adopted after rough rolling, the cold rolling is achieved by single-frame rolling or multi-frame once or twice cold rolling, the temperature of a steel strip entering a finishing mill is 1,100 to 1,250 DEG C, the output temperature of the finishing mill is larger than 800 DEG C, and laminar cooling is adopted after rolling to reach a final cooling temperature of 400 to 800 DEG C. By controlling the state of a depressant in continuous casting and by adopting high-temperature, short-time and rapid hot rolling process, etc, the invention can achieve uniform product performance, high quality, reduced energy consumption as well as high efficiency.

Description

technical field [0001] The invention belongs to the technical field of metallurgy, and relates to a method for producing silicon steel by continuous hot rolling, in particular to a method for producing an oriented silicon steel plate. Background technique [0002] The production of oriented silicon steel generally adopts a straight arc continuous casting machine, and the thickness of the casting slab is more than 200mm. Due to the thicker casting slab, the cooling time is longer, the surface temperature of the casting slab is lower, and the precipitation of inhibitors in the steel is larger. , the production feature of this kind of slab is to use higher temperature and longer heating time to make the inhibitor into solid solution, so as to achieve the purpose of producing grain-oriented silicon steel. [0003] The other is to use thinner CSP production, but this production line uses tunnel furnace heating, the heating time and temperature cannot be guaranteed, and the inhibi...

AI Technical Summary

Problems solved by technology

[0005] 1 There is no mature production process. Since the production of oriented silicon steel in medium and thin slabs has problems such as thicker inhibitors in thick slabs and difficult floating of inclusions in thin slabs, although it has been weakened, it still needs to adopt reasonable technological measures. Solved, it cannot be realized by using thick slab production method

[0006] 2 Unreasonable selection of supercooling degree causes serious segregation of billet composition, which affects product performance stability

[0007] 3 Since the slab is thinner than the thick slab, the reduction rate is small, which is not conducive to the crushing of inclusions and affects the performance of the finished product

[0008] 4 At present, there is no heat preservation measure for the slab after conventional slab continuous casting, and the temperature drop of the slab is relatively fast, resulting in a large amount of precipitation and growth of inhibitors

[0009] 5 Rough rolling is generally exposed on the roller table when it is waiting for temperature, the cooling is uneven, the temperature difference of the coil is large, and the precipitates are uneven everywhere, resulting in large fluctuations in performance