Sintered Calcium Aluminate

Sintered refining slag (calcium aluminate) is made by sintering high-quality materials, and it has the functions of rapid slag formation, arc burial, slag making, absorption of steel liquid inclusions, desulfurization, etc. It has a strong deoxidation and desulfurization effect, can reduce gases in steel, and reduce inclusions in steel. This product is made by sintering or melting various selected raw materials to produce minerals mainly composed of 12CaO·7Al2O3, with a content of more than 85%. The large amount of calcium components can react with oxygen and sulfur in the molten steel to generate low-melting-point products that easily float, achieving the purpose of purifying the molten steel. In ladle refining, it can effectively shorten the steelmaking time and has a strong ability to absorb non-metallic inclusions in steel, significantly improving the purification of molten steel.

Features:

Metallurgical Effect Analysis

Desulfurization

The desulfurization of the refining agent during the refining process mainly utilizes the ratio between the slag and molten steel to control the sulfur content in the steel. Since sulfur is one of the common harmful elements in steel, it has many adverse effects on the properties of steel. Therefore, the greater the desulfurization capacity of the refining agent, the lower the sulfur content in the molten steel.

Deoxidation

There are two types of oxygen in molten steel: dissolved oxygen and combined oxygen. Combined oxygen can be removed as inclusions by the slag. During the refining process, a certain amount of deoxidizer is added to convert the dissolved oxygen in the steel into oxides to the greatest extent possible. The oxides then float due to their buoyancy and appropriate low-argon blowing agitation, eventually entering the slag layer and being absorbed. In addition, oxygen obeys the distribution law in the slag and molten steel. When a reducing refining agent comes into contact with the molten steel, the dissolved oxygen in the steel can enter the slag through diffusion, thereby deoxidizing the molten steel.

Inclusion Adsorption

During the refining process, due to the strong stirring action of low-argon blowing, the emulsified slag and molten steel come into extensive contact, greatly increasing the contact opportunities between the slag and impurities in the steel (especially large particles). Since the refining slag is an ionic melt formed by oxides in a molten state, and the impurities in the steel are also mostly oxide melts, according to the principle of like dissolves like, the impurities in the steel easily combine with the slag droplets, dissolving and combining to form larger slag droplets, which then capture other impurity droplets. Larger droplets, due to their greater buoyancy, quickly float and merge into the slag layer on the surface of the molten steel. The emulsified slag droplets can become nucleation crystals for deoxidation products, allowing deoxidation products to quickly form stable compounds, reducing the chemical potential of deoxidation products in the molten steel, making the reaction proceed in a direction favorable for deoxidation, and accelerating the deoxidation reaction. Due to the high Al2O3 content in the refining agent, the slag composition becomes very stable and does not change its properties with the introduction of deoxidation products (Al2O3). Therefore, the refining agent always maintains a very stable ability to deoxidize, desulfurize, and remove impurities.

Protective Effect on the Furnace Lining

Due to the presence of approximately 8%-10% MgO in the refining agent, the MgO in the slag basically reaches saturation. Therefore, only a small amount of MgO in the lining near the slag line can dissolve into the slag, reducing the erosion of the lining. Secondly, the refining agent has a good foaming and arc-burying effect, reducing the erosion of the lining by the electric arc, thereby extending the service life of the ladle.

The materials can be blended and the specifications adjusted to meet the needs of refining steel according to the composition of the user's molten steel.

Packaging and Delivery

Process Flow Chart