A ferro alloy composed of silicon and iron is Ferro Silicon. The silicon content in this ferro alloy is between 15% and 90%. There is high proportion of iron silicide in it. Other elements present in Ferro Silicon are calcium and aluminium. This corrosion and abrasion resistant ferro alloys is silvery grey to dark grey in color. Its particles are available in different forms, like milled, crushed and lumps. It might react with water for hydrogen production. Some of the largest producers of this odorless Ferro Silicon are India, USA and China, responsible for global supply.
Production
Ferro Silicon production process starts with the blend of coke and silica (or sand), which is then subjected to reduction process in the presence of any iron source. Some of the most common iron sources are mill scale and scrap iron. If the silicon content is up to 15%, ferro silicon is made in blast furnaces lined with acid fire bricks. If the silicon content is larger than aforementioned, then electric arc furnace is used. The most common ferro silicon formulations include silicon content of 15%, 45%, 75%, and 90%. The rest content used is iron, along with about 2% of calcium and aluminium. Larger silica content prevents silicon carbide formation.
Applications