Ferroalloy is one of the essential and important raw materials for steel industry and mechanical casting industry. With the continuous and rapid development of the iron and steel industry, the variety of steel has been continuously expanded and the quality has been improved, which has put forward higher requirements for ferroalloy products.
(1) Used as a deoxidizer. The bonding strength of various elements in molten steel to oxygen, that is, the deoxidation ability, is in the following order from weak to strong: chromium, manganese, carbon, silicon, vanadium, titanium, boron, aluminum, zirconium, and calcium. Generally, iron alloys composed of silicon, manganese, aluminum, and calcium are commonly used for deoxidation in steelmaking.
(2) Used as alloying agent. The elements or alloys used to adjust the chemical composition of steel to alloy steel are called alloying agents. Commonly used alloying elements are silicon, manganese, chromium, molybdenum, vanadium, titanium, tungsten, cobalt, boron, niobium, etc.
(3) Used as a casting nucleus inoculant. In order to change the solidification conditions, some iron alloys are usually added as nuclei before casting to form the center of the grains, so that the formed graphite becomes fine and dispersed, and the grains are refined, thereby improving the performance of the casting.
(4) Used as reducing agent. Ferrosilicon can be used as a reducing agent for the production of ferromolybdenum, ferrovanadium and other ferroalloys, and silicon-chromium alloy and silicon-manganese alloy can be used as a reducing agent for refining medium and low carbon ferrochromium and medium and low carbon ferromanganese respectively.
(5) Other uses. Ferroalloys are also increasingly used in the non-ferrous metallurgy and chemical industries.