Weather resisting steel produced by strip casting and production method thereof

Abstract

The invention discloses a weather resisting steel produced by strip casting and a production method thereof. The weather resisting steel comprises the following components in mass percentage: 0.06-0.12% of C, 0.20-0.50% of Si, 0.20-0.50% of Mn, 0.15-0.22% of P, less than or equal to 0.008% of S, 0.65-0.80% of Cu, 0.30-0.70% of Cr, 0.12-0.40% of Ni and the balance Fe and inevitable impurities; molten steel smelted according to the above components is poured into a furnace hearth formed by a water-cooled casting roll and a side seal device which rotate oppositely and forms a casting band by being cooled by the water-cooled casting roll; the casting band is sent into an on-line mill via a pinch roll to be rolled into a hot-rolled strip, and the thickness of the casting band is 1-5mm; the cooling speed of the molten steel at least reaches 300 DEG C / s when contacting with the surface of a two-roller caster casting roll; the casting band after leaving the casting roll is hot rolled on line and has the deformation degree of 30-45%.The steel band produced with the strip casting process of the invention has no possibility of macrosegregation of elements such as phosphorus, copper and the like, is convenient and economic to produce, saves energy and lowers consumption.

Description

technical field [0001] The invention relates to a method for producing atmospheric corrosion-resistant steel, in particular to a strip continuous casting method for producing atmospheric corrosion-resistant steel and a production method thereof. Background technique [0002] Thin strip continuous casting technology is a cutting-edge technology in the field of metallurgy today. It has been developed for more than 140 years since Henry Bessemer proposed this idea (US Patent49053) in 1865, but at that time due to manufacturing technology and control Technology and other related technologies are not mature enough, so that this technology is basically at a standstill. It was not realized in the continuous casting and rolling process of Al until the middle of the 20th century, which once again attracted people's attention in the field of steel manufacturing. [0003] Twin-roll strip continuous casting is to directly pour hot molten steel from the ladle through the tundish and sub...

AI Technical Summary

Problems solved by technology

[0008] (1) Long process flow, high energy consumption, multiple unit equipment, and high infrastructure costs lead to high production costs;

[0009] (2) There are many quality defects, the yield is low, and the atmospheric corrosion-resistant steel contains high content of phosphorus and copper and other elements that are easy to segregate. The traditional process is easy to cause local macro-segregation of phosphorus, copper and other elements due to slow solidification and cooling , resulting in the anisotropy of the slab and the appearance of macroscopic cracks, resulting in a low yield

[0010] (3) The weather resistance is not high. The weather resistance of atmospheric corrosion-resistant steel mainly depends on the joint action of phosphorus and copper in the steel. From the easy segregation characteristics of phosphorus and copper elements in the traditional process mentioned above, the composition of phosphorus and copper in the composition system The content usually takes the lower limit, and it cannot reach a higher content. The content of phosphorus is generally not higher than 0.12, and the content of copper is generally below 0.55. This result sacrifices the weather resistance of the steel to a certain extent.

However, in the traditional process, the rough rolling mill has to repeat several passes to thin the slab to the specifications required before finishing rolling.

Images