Method for reducing color difference defects on IF steel surface

Abstract

The invention provides a method for reducing color difference defects on an IF steel surface, which is used for mitigating the color difference defects on the IF steel surface. The method comprises the steps of reducing the emulsion concentration and the emulsion jet flow of a fifth acid rolling rack so as to reduce the accumulation of an emulsion on the upper surface of a steel plate and betweenrollers; reducing the content of iron powder in the emulsion of the fifth acid rolling rack through a magnetic filter; reducing the contact angle of rolling oil in the emulsion so as to improve the spread uniformity of an oil film; and increasing the leveling elongation of the flat segment of a steel strip after continuous annealing. The method solves the technical problem of the color differencedefects on the IF steel surface in the prior art, therefore achieving the technical purpose of improving the quality of the IF steel surface.

Description

technical field [0001] The invention relates to the technical field of steel rolling, in particular to a method for reducing color difference defects on the surface of IF steel. Background technique [0002] IF steel is a kind of automotive steel plate with excellent deep drawing performance. It has the characteristics of good plasticity, high anisotropy value, high work hardening index and no aging. It is mainly used for stamping parts with complex shapes. However, due to the low strength of this series of steels, the flattening reduction rate after annealing is small, and the upper surface of the steel plate is prone to chromatic aberration defects. Chinese patent CN107893155 A discloses a method for eliminating color difference defects on the surface of phosphorus-containing high-strength IF steel. This method partially eliminates the color difference defects on the surface of IF steel through the control of rolling temperature, coiling temperature and reduction rate, and...

AI Technical Summary

Problems solved by technology

However, due to the low strength of this series of steels, the flattening reduction rate after annealing is small, and the upper surface of the steel plate is prone to color difference defects.

Chinese patent CN107893155 A discloses a method for eliminating color difference defects on the surface of phosphorus-containing high-strength IF steel. This method partially eliminates the color difference defects on the surface of IF steel through the control of rolling temperature, coiling temperature and reduction rate, and cannot be completely avoided. Chromatic defect

The solution of some steel enterprises to deal with the chromatic aberration defect of IF steel is to carry out a weak pickling process after the annealing process, which can partially reduce the chromatic aberration of the steel plate surface, but this solution increases production costs, reduces production efficiency, and produces certain environmental pollution.

In addition, the surface chromatic aberration defect cannot be eliminated in the subsequent processing, which will eventually affect the appearance of the finished product