The basic requirements for maintenance slag in die-casting in steel making are low density, low melting point, and alkalinity (CaO / SiO2) ratio less than 1, proper melting rate and good spreadability. Wollastonite has high-temperature fluxing characteristics, fluctuating chemical composition, high purity, and alkalinity (CaO / SiO2) tends to be neutral. This excellent characteristic provides ideal raw materials for the maintenance casting materials of metallurgical steelmaking, especially wollastonite contains very little Al2O3. Therefore, the metallurgical maintenance slag produced has a strong ability to adsorb harmless Al2O3 in molten steel, so it is generally Used in the metallurgical industry. The raw materials for metallurgical additives require wollastonite ≥50%, calcite ≤50%, quartz ≤5%, S≤0.01%, P≤0.01%. In the world, 12% to 15% of wollastonite is consumed in this category every year.

 

Nowadays, from ordinary carbon steel, manganese steel to stainless steel continuous casting, and the slag form from small square billet, small gas billet, large slab to out-of-furnace refining, etc., maintenance slag based on wollastonite as the base material is commonly used, quickly replacing the price Expensive export maintenance slag has played a role in promoting the development of the metallurgical steelmaking industry.