silicon carbide metallurgy
When using in electric furnace, the size of silicon carbide metallurgy shall be 0.5-3mm, for easy to melt and absorb. When using in copula furnace, the size of SiC metallurgy shall be bigger to avoid efflation by blast air. In high temperature, silicon carbide metallurgy grade will decompose into carbon and silicon ions, they will react with oxygen, then into the liquid iron respectively, and form the core of graphite. As we all know, silicon and carbon have strong inoculation ability, it will help to make cast iron. The adding amount of SiC metallurgy is 0.5-5.0%. For years people are using silicon carbide metallurgy in production of casting, and had very effective result and experience.
According to current experience, the most commom grades are silicon carbide 88 and 90%, adding amount 2.5%. Because the melting point of silicon carbide is as high as 2700℃, so the melting process is longer, we need to add it before other alloys and additives, usually it is added at whole casting procedure’s one third time to half time, so as to let it have enough time for melting and reaction. In all, silicon carbide metallurgy can replace ferrosilicon and increase the number of graphite, and enhance mechanical properties of the casting.