Method for rolling high-strength IF steel in ferrite area

Abstract

The invention relates to a method for rolling a high-strength IF steel in a ferrite area. The high-strength IF steel is formed by adding solid solution strengthening alloy elements such as Mn<=1.8 %, P<=0.1 %, Cr<=0.5 %, Mo<=0.5 % of and the like into common Nb +Ti-IF steel grades so as to improve strength of the IF steel; the high-strength IF steel is produced with a heating temperature<=1150 DEG C, heating time between 0.5 hour and 1 hour and a starting rolling temperature 1100 DEG C; rough rolling is acted in an austenitic area, and screw-down rate of the rough rolling is 80%, thereby austenitic crystal particles are refined after rolled roughly; finish rolling is performed in the ferrite area, finish rolling temperature is <=780 DEG C, and then the IF steel is coiled away after laminar flow cooling is performed. The method substantially decreases oxidized steel loss produced by using the method, improves quality of strip steels, and can produce wider and thinner hot rolled plates and strips by consuming less energy.

Description

technical field [0001] The present invention relates to the rolling technology of steel plates, in particular to the method of rolling high-strength IF steel with high strength and excellent deep drawability to finally form ferrite strip steel with required final thickness. Background technique [0002] With the development of industrial technology, energy and environmental issues have become major social issues, and the automobile industry is no exception. In recent years, my country's automobile industry is developing rapidly with an annual growth rate of 10% to 15%. The changing demand of the automobile market continues to put forward requirements for the output and quality of steel materials. In particular, the requirements for weight reduction, energy saving, safety and environmental protection of automobiles make the development and application of high-strength steel plates more and more important. [0003] The strength and plasticity of steel are generally contradict...

AI Technical Summary

Problems solved by technology

However, the strength of this kind of steel is often relatively low, while the traditional high-strength IF steel obtains relatively high strength by adding alloy elements such as P and Mn, but also greatly damages the deep drawability.

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