TECHNOLOGICAL PRINCIPLES OF THE PRODUCTION OF CLEAN COLD-RESISTANT STEELS FROM PIG IRON WITH LOW CONTENTS OF MANGANESE AND SILICON

摘要

The wide use of quality steels is significantly tightening the requirements on the cleanliness of steel with respect to its content of harmful impurities and inclusions. One of the most important problems in this connection is the creation of an efficient and economical method for desulfurizing pig iron and steel. Solving this problem is particularly important for Russian metallurgy, since Russia is the largest nation in the Northern Hemisphere and thus needs to expand its production of cold-resistant steels. One key characteristic of this type of steel is an ultralow (0.001-0.005 percent) sulfur content. Sulfur is removed from an iron-carbon melt in accordance with reaction: [S] + Me = (MeS). The elements Ce, Ca, Mg, and Na may participate as the metal in this reaction in the form of a liquid, solid (powder), or vapor. The desulfurizing ability of these elements decreases from Ce to Na, in accordance with the change in the thermodynamic stability of the oxides and sulfides that they form.