Production method of ultra-low-carbon steel for sedan car cortical plate

Abstract

The invention provides a producing method for ultra low steel carbon used in car outer plate, characterized in that liquid steel is cast into plate slab in the pulling speed of 1.5-4m / min; the thickness of plate slab is 100-170mm; casting machine adopts dynamic light pressure and crystallizer electromagnetic braking technology and tundish superheat is 20-45deg.C; the plate slab is installed in heat directly and the charging temperature is more than 800deg.C; the plate slab is heated to 1150-1250deg.C in heating furnace; after the temperature is maintained for 30-90min rough rolling cogging iscarried out. By adopting continuous rolling and casting short-flow process of medium-thin plate slab and collocating casting machine and heating furnace compactly quick charging is realized; chargingmaterial temperature is improved; problems of large investment and high energy consumption in conventional process are solved; inner limitation generated in continuous casting process of thin plate iseliminated; it is guaranteed that product is provided with good surface quality and stable mechanical property.

Description

technical field [0001] The invention relates to a method for manufacturing steel for automobiles, in particular to a method for producing ultra-low carbon steel for car outer panels by using a medium-thin slab continuous casting and rolling production line, and belongs to the technical field of metallurgical metal pressure processing. Background technique [0002] At present, the traditional production process is used to produce ultra-low carbon steel for automobiles, through converter steelmaking, slab continuous casting, heating in the heating furnace, rough rolling mill rolling, finishing rolling mill rolling, laminar cooling, coiling, pickling, Cold rolling, bell annealing or continuous annealing. The production process is mature and the product quality is good. Continuous casting at low casting speed on traditional continuous casting machine, slab thickness ≥ 200mm, casting speed at 0.8-1.3m / min. Using the traditional hot-rolling process to produce steel for automobil...

AI Technical Summary

Problems solved by technology

However, when this process is used, the production capacity is low, and the quality of the slab cannot be guaranteed (for example, when the thin slab is used to produce automobile steel, the strength is very high and cannot meet the requirements; in addition, due to the high casting speed, the slab is mixed with Many), unable to produce varieties with high surface grade requirements, such as car outer panels, etc.