Manufacturing method of thin slab casting and rolling high-surface-quality medium-high carbon steel

Abstract

The invention discloses a manufacturing method of thin slab casting and rolling high-surface-quality medium-high carbon steel. The manufacturing method comprises the following steps that (1) smelting and continuous casting are carried out to obtain a blank, and the thickness of the casting blank ranges from 50 mm to 70 mm; (2) the continuous casting blank is heated in a heating furnace, the temperature of the casting blank fed in the furnace ranges from 812 DEG C to 1053 DEG C, the temperature of the casting blank discharged out of the furnace ranges from 1107 DEG C to 1182 DEG C, the time of the casting blank in the furnace ranges from 26 min to 41 min, the volume fraction of oxygen in a hearth is controlled to range from 1.1% to 4.8%, and high-pressure water descaling is carried out before the casting blank is fed in the heating furnace and after the casting blank is discharged out of the heating furnace; (3) at least six passes of finish rolling are carried out, in the finish rolling process, the rolling reduction rate of a first rack and the rolling reduction rate of a second rack are controlled to range from 50% to 60%, high-pressure water descaling is carried out between the finish rolling first rack and the finish rolling second rack and between the second rack and a third rack, and the finish rolling temperature of finish rolling ranges from 880 DEG C to 910 DEG C; and (4) cooling and rolling are carried out to obtain a finished steel roll. According to the thin slab casting and rolling high-surface-quality medium-high carbon steel produced through the method, the thickness of oxide scale is only 3.9 micrometers to 6.9 micrometers, the volume fraction of FeO in the oxide scale structure reaches 51%-72%, the acid pickling difficulty is greatly reduced, and the product surface quality is improved.

Description

technical field

[0001] The invention relates to a medium-high carbon steel with high surface quality, in particular to a method for manufacturing medium-high carbon steel with high surface quality by continuous casting and rolling of thin slabs. Background technique

[0002] Medium-high carbon steel has the characteristics of high strength, high hardness and high wear resistance. It is mainly used to make various cutting knives and special tools. It is widely used in papermaking, forestry, rubber, plastics, textiles, electrical appliances, light industrial machinery and other fields. .

[0003] At present, the production process of most medium and high carbon steel products is: steelmaking → continuous casting → heating → hot rolling → pickling → cold rolling. Before cold rolling of medium-high carbon steel, it is necessary to remove the scale on the surface of the hot-rolled strip, and then carry out the next step of deep processing. Generally, pickling is used as the remo...

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