The application prospect of high carbon silicon Si65C15: With the development of the national economy, the requirements for steel types and quality are increasing day by day, and the iron and steel smelting technology has been developed from the original one-step steelmaking to the two-step method.
One-step steelmaking, that is, two steps of primary smelting and refining. Control the temperature of molten steel and the content of main elements through one refining, and carry out deoxidation, impurity removal and alloying through refining to obtain steel grades of expected variety and quality. In steelmaking, before entering the refining furnace, the surface of molten steel is covered with insulating agent to prevent cooling of molten steel and surface oxidation. After entering the refining furnace, deoxidation and alloying are required to absorb deoxidation products and impurities in the steel. Harmful impurities achieve the purpose of purifying molten steel. Deoxidation of molten steel ultimately uses metallic aluminum. The melting point of the deoxidized product, alumina, is 2050°C and exists in the form of dendrites or needles in molten steel. When the molten steel condenses, it will cause dendritic or needle-like oxide inclusions in the steel, which will affect the quality of the steel.
Therefore, people have researched and developed deoxidizers for steelmaking. Before the use of high-carbon silicon Si65C15, the deoxidizers generally used in steelmaking mainly include silicon-calcium cored wire, aluminum wire, aluminum manganese ferromanganese, steel core aluminum, calcium carbide and silicon carbide, etc. of oxygen. Generate non-metallic compounds, form precipitates, float up to the slag layer, and remove to obtain pure molten steel. When aluminum is used as a deoxidizer to deoxidize molten steel by precipitation, the deoxidation speed is fast and the cost is low. However, during the dissolution process, aluminum tends to float to the surface of molten steel, and the deoxidation efficiency is low. In addition, the deoxidation product alumina has a high melting point and is brittle. After processing, it is easy to form sharp-edged inclusions, which will deteriorate the fatigue resistance of the steel and shorten the service life of the steel. At the same time, it will also affect the mechanical properties of the steel, reduce the high temperature strength of the steel; loss, resulting in a decrease in utilization. Therefore, it is necessary to develop a high-carbon silicon Si65C15 deoxidizer for steelmaking with high deoxidation efficiency.