Preparation technology for fine-grained steel 510L

Abstract

A preparation technology for fine-grained steel 510L belongs to the field of steelmaking industry, can reduce the cost, improve the grain size grade of a product and the cold working performance of steel material, and has the following technological processes: a pre-processing process, that is, removing sulphur from molten iron by blowing passivated magnesium to the molten iron, and controlling the passivated magnesium blowing quantity, the blowing pressure and the blowing flow rate, so as to prolong the contact time between magnesium and the molten iron; and making steel with a revolving furnace, that is, a sublance steel making technology is adopted, mid-carbon fe-mn, ferrosilicon and ferro-aluminum are added into output steel for deoxygenation and alloying, the content of oxygen in the molten steel is controlled after deoxygenation and alloying, finally Nb iron is added into output steel for micro-alloying of Nb in the steel liquid, a steel ladle is stirred through bottom argon blowing during steel outputting, refining is carried out after micro-alloying of steel output by the revolving furnace, the ingredients and the temperature of the molten steel are trimmed by adding alloy or feeding aluminum wire by a wire feeding machine; moreover, an LF Furnace adopts the soft argon blowing process so as to remove foreign materials in the molten steel maximally, which improves the cleanliness of the molten steel; and the steel rolling process adopts a method capable of controlling rolling and cold. The invention has the advantages that the product quality is improved considerably; the cost is reduced; the grain size grade of the product is improved; and the cold working performance of the steel material is improved.

Description

technical field [0001] The invention belongs to the field of steelmaking industry. Background technique [0002] The production process of 510L in the past: blast furnace molten iron→pre-desulfurization of molten iron→converter smelting→refining (argon blowing or LF refining)→continuous casting→slab heating→rough rolling→finish rolling→layer cooling→coiling→storage. The 510L produced by the existing process route has high sulfide content, and the rolling steel lacks a strict controlled rolling and controlled cooling system, and its grain size grade is difficult to reach above 10 grades. Contents of the invention [0003] The purpose of the present invention is to provide a preparation process of fine-grained steel 510L that can reduce costs, increase the grain size level of products, and improve the cold working performance of steel products. [0004] Process flow of the present invention is: [0005] a. Pretreatment process, using the method of spraying passivated magne...

AI Technical Summary

Problems solved by technology

The 510L produced by the existing process route has high sulfide content, and the rolling steel lacks a strict controlled rolling and controlled cooling system, and its grain size level is difficult to reach above 10

Images