A kind of smelting method of high phosphorus if steel with high cleanliness

Abstract

The invention discloses a smelting method for high-phosphorus IF steel with high cleanliness, and belongs to the technical field of high-phosphorus steel smelting. It includes the following steps: the oxygen supply in the converter reaches 200m 3 ‑500m 3 In the first stage, add the first batch of materials, wherein the first batch of materials includes lime and magnesium balls, and the lime in the first batch of materials is 70% of the total amount of lime added; the oxygen supply in the converter reaches 2500m 3 ‑2800m 3 In the second stage, add the second batch of materials, wherein the second batch of materials includes lime, and the lime in the second batch of materials is 20% of the total amount of lime added; the oxygen supply in the converter reaches 6000m 3 ‑6300m 3 In the third stage, the third batch of materials is added, wherein the third batch of materials includes lime and silicon carbide, and the lime in the third batch of materials is 10% of the total amount of lime added. In view of the existing technical problems, it is necessary to study a smelting method of high-phosphorus IF steel with high cleanliness, which can effectively ensure that high-phosphorus IF steel does not splash during the smelting process, and has low oxygen content at the end point and high cleanliness.

Description

technical field [0001] The invention belongs to the technical field of high-phosphorus steel smelting, and more particularly relates to a high-phosphorus IF steel smelting method with high cleanliness. Background technique [0002] Due to its high strength and ultra-deep drawability, high-phosphorus IF steel has developed rapidly in recent years. This type of steel can be used to manufacture complex automotive structural parts, such as car extension brackets, suspension mounting beams, and steering gear installations. Support beams, reinforcing plates, etc., and are gradually used in automotive panels, so the requirements for the cleanliness of molten steel are higher. [0003] High-phosphorus IF steel requires high tapping temperature and high phosphorus in molten steel during the smelting process, resulting in rapid temperature rise in the early stage of smelting and low basicity in the furnace, which is very likely to cause explosive splashing. Existing smelting methods ...

AI Technical Summary

Problems solved by technology

[0003] In the smelting process of high-phosphorus IF steel, due to the high tapping temperature and high phosphorus in molten steel, the temperature rises rapidly in the early stage of smelting, and the alkalinity in the furnace is low, which can easily cause explosive splashing

The existing smelting methods are as follows: ① Control the occurrence of explosive splashing by increasing the amount of lime added and increasing the alkalinity of slag. However, this method results in low phosphorus content in molten steel, and a large amount of ferrophosphorus needs to be added in the subsequent process, which costs more High; ②By increasing the amount of smelting scrap steel and reducing the heating rate in the early stage, the occurrence of explosive splashing can be effectively contained, but the lack of heat during the measurement of the sub-gun TSC can easily cause end-point overoxidation and high end-point oxygen, affecting high phosphorus Cleanliness of IF steel