A kind of ocr17 continuous casting slab and production method thereof

Abstract

The invention discloses an OCr17 continuous casting blank and a production method thereof. The continuous casting blank comprises the following chemical components in percentage by mass: 0.04-0.06% of C, 0.25-0.45% of Si, 0.40-0.55% of Mn, 0.035% or less of P, 0.030% or less of S, 16.50-16.75% of Cr, 0.60% or less of Ni, and the balance of Fe and inevitable impurities. The production method comprises the steps of: control of a continuous casting machine crystallizer water flow, a secondary cold water flow and crystallizer electromagnetic stirring parameters, slow cooling of the continuous casting blank and casting blank angle finishing chamfering plane width control. The method enables the surface pass percent of the continuous casting blank of rolled steel to reach above 99%, and guarantees elimination of surface and subsurface cracks of the continuous casting blank; and through angle finishing, the angle rolling broadening deformation is reduced, the angle temperature drop is reduced, the OCr17 wire folding and cracks are eliminated, the wire rod primary inspection pass percent is above 99%, and the acid washing secondary inspection pass percent is above 95%.

Description

technical field [0001] The invention belongs to the technical field of metallurgy, and in particular relates to an 0Cr17 continuous casting slab and a production method thereof. Background technique [0002] 0Cr17 is widely used in household appliances, automobiles and other industries due to its good corrosion resistance and bright surface of processed parts. [0003] At present, there are many enterprises producing 0Cr17 stainless steel wire rods in China, and the casting slabs for wire rod rolling are continuous casting slabs. Due to the poor heat transfer performance of this steel grade, the temperature drop gradient during the solidification process is large, and the content of refined grain elements is low, which leads to its small size. The equiaxed crystal layer is thin and the columnar crystals are developed, so it is easy to generate cracks on the surface and subcutaneous of the slab and inherit it to the rolling process, causing cracks in the wire rod. During the ...

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Problems solved by technology

[0003] At present, there are many enterprises producing 0Cr17 stainless steel wire rods in China, and the casting slabs for wire rod rolling are continuous casting slabs. Due to the poor heat transfer performance of this steel grade, the temperature drop gradient during the solidification process is large, and the content of refined grain elements is low, which leads to its small size. The equiaxed crystal layer is thin and the columnar crystals are developed, so it is easy to generate cracks on the surface and subcutaneous of the slab and inherit it to the rolling process, causing cracks in the wire rod. During the cooling process of the slab, due to the coarse crystal grains, cracks may even occur due to thermal stress. Continuous casting slab fracture

[0004] Although there are rounded corners at the corners of the continuous casting slab, due to the limitation of the copper tube processing of the continuous casting machine mold and the cooling factors of the slab, the radius of the slab fillet is almost uncontrollable, which results in a large number of slabs having a small fillet radius. Due to the small fillet radius of the billet, the excessive deformation of the corner and the decrease in plasticity due to the large temperature drop during rolling cause the surface of the wire rod to appear folded and cracked to varying degrees, resulting in subsequent cold heading cracks

If the casting slab fillet radius is increased through the design of the copper tube of the mold, it will not only affect the amount of steel passing through the copper tube of the mold, but also easily lead to a steel breakout accident in the continuous casting machine

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