What is the difference between silicon metal 441 and 553?

Silicon metal as an additive of non-iron based alloys has a very wide range of applications in steelmaking industry, so where is silicon metal specifically used? What is the difference between silicon metal 553 and 441? Let’s take a closer look.

Silicon metal is also known as crystalline silicon or industrial silicon, and its main use is as an additive to non-iron based alloys. Silicon metal is a product made of quartz and coke smelted in an electric heating furnace. The content of silicon element is about 98%, and the other impurities are iron, aluminum, calcium and so on.
In our country, silicon metal is usually classified according to the content of three main impurities: iron, aluminum and calcium. According to the percentage content of iron, aluminum and calcium in silicon metal, silicon metal can be divided into 553, 441, 411, 421, 3303, 3305, 2202, 2502, 1501, 1101 and other different grades. In each brand, the first and second code names are the percentage content of iron and aluminum, and the third and fourth two represent the content of calcium, so 553 represents the content of iron, aluminum and calcium in silicon metal is 0.5%, 0.5%, 0.3%; 441 represents that the content of Fe, Al and Ca in metal silicon is 0.4%, 0.4% and 0.1%
It can be seen that the difference between 441 and 553 is the difference in purity. The silicon content of 553 is ≥98.7%, while the silicon content of 441 is ≥99.1%. Specifically, the industrial silicon is obtained by the reaction of quartz and carbon at high temperature in the ore-thermal furnace: SIO2+C=SI+CO2. Quartz has poor quality and good quality, as a reducing agent carbon also has poor quality and good quality, the difference of these raw materials determines the purity of industrial silicon. From a cost perspective, it is clear that the higher the quality of the raw materials, the more expensive.