The role of silicon carbide for casting

The more common silicon carbide in the market is mainly black silicon carbide and green silicon carbide. Ordinary silicon carbide is below 90%, more green and other colors. Silicon carbide for casting is more than 80%, in the electric furnace with materials, the particles are finer, 0.5-3 mm, so that it is easy to melt, absorb, used in the cupola, the block is larger, so as not to be washed out by strong air flow.
At high temperatures, silicon carbide decomposes into carbon and silicon ions, and their chemical characteristics are to first react with oxygen, so it has the oxidation of molten iron, and then enters molten iron respectively, first becoming the crystalline core of graphite. Both carbon and silicon have a strong gestational effect, so they are a good help for electric furnaces and low-carbon ferrosilicon smelting. The amount of silicon carbide added is generally about 0.5-5%. Silicon carbide, especially in smelting, can increase the graphite core and increase the number of graphite balls of ductile iron, which is very beneficial to improve the graphite morphology of gray iron.