Pure silicon is a crystalline material with a metallic luster and a steel gray color. It is hard and brittle, and belongs to the non-metallic category. Silicon has an atomic weight of 28.08, a density of 2300kg/m3, and a melting point of 1683K. Iron has a silver white metallic luster, good ductility, conductivity, and thermal conductivity, with a density of 7.86kg/cm3 and a melting point of 1435K.

Ferrosilicon is an iron alloy composed of iron and silicon. The melting point of ferrosilicon increases with the increase of silicon content, and the melting point of standard ferrosilicon is lower than 1634K. The alloy of silicon and iron is prone to segregation, and the difference in silicon content between the upper and lower parts of the alloy bond is more than 20%. The thicker the alloy key and the longer the cooling time, the more severe the segregation. Therefore, it is usually required that the washing and casting thickness of silicon iron ingots should not exceed 100mm