Alkaline earth metal oxide composite molten steel refining agent and preparing method thereof

Abstract

The invention discloses an alkaline earth metal oxide composite molten steel refining agent and a preparing method thereof, and belongs to the technical field of molten steel furnace external refining. The composite refining agent is formed in the manner that alkaline earth metal oxide powder, alkaline earth metal carbonate powder and a self-reduction reducing agent serve as main raw materials, and after the alkaline earth metal oxide powder, the alkaline earth metal carbonate powder and the self-reduction reducing agent are mixed according to a certain proportion, a proper number of bonding agents are added, and the mixture is pressed into balls. After the composite molten steel refining agent is added into a steel ladle at an LF or RH or VD refining station, in the refining, vacuum and reducing atmosphere with the molten steel temperature larger than 1,500 DEG C, alkaline earth metal oxide in the refining agent is partly reduced through the self-reduction reducing agent, oxygen in top slag of the steel ladle can be effectively removed through Ca, Mg and Ba obtained through reduction, a dynamic condition is provided for following desulfuration, and the function of deep removing of [O] and [S] is achieved for the molten steel while Al does not need to be additionally added to carry out oxygen removing on the top slag of the steel ladle; and therefore the production technology is obviously simplified, operation is easy, and the production cost is greatly reduced.

Description

technical field [0001] The invention belongs to the technical field of molten steel refining outside the furnace, and more specifically relates to an alkaline earth metal oxide composite molten steel refining agent and a preparation method thereof. Background technique [0002] In recent years, with the continuous improvement of the production technology and equipment level of my country's iron and steel industry, some super-large iron and steel enterprises have reached the world's advanced level, which has led to the further optimization of the variety structure, the strip ratio has increased significantly, and the output of high-quality pure steel has also increased significantly . High-quality molten steel refining technology, high-efficiency continuous casting production technology, and full use of the physical metallurgical capabilities of rolling mills are key technologies adopted by advanced iron and steel enterprises in high-efficiency, high-quality, and low-cost prod...

AI Technical Summary

Problems solved by technology

[0008] The purpose of the present invention is to overcome that in the prior art, when pure steel is produced through the combined use of pre-melted refining slag and composite alloy, metal aluminum or aluminum-containing composite alloy must be used to carry out precipitation deoxidation and diffusion deoxidation on molten steel and ladle top slag , so that the production process is complicated, and the product Al after deoxidation 2 o 3 It has a great impact on steel quality, poor castability of molten steel, increased complexity of subsequent processing procedures and insufficient cost, and provides an alkaline earth metal oxide composite molten steel refining agent and its preparation method