Ferroalloy known as steelmaking materials for it is used as additive in the casting or steelmaking process,actually,its a general term for alloys composed of iron and elements such as silicon,manganese,chromium,and titanium.
With the development of modern science and technology, the types of ferroalloys are constantly expanding. There are many varieties of ferroalloys and there are many classification methods. They are generally classified according to the following methods.
| Single iron alloy | Alloys containing only one alloying element are called monoferroalloys. Its main varieties include ferrosilicon, ferromanganese, ferrochrome, ferromolybdenum, ferrotitanium, ferrotungsten, industrial silicon, ferroboron, ferrovanadium, metallic manganese, etc. |
| Composite iron alloy | Those containing two or more alloying elements are called multi-component ferroalloys. The main varieties are silicon-calcium alloy, manganese-silicon alloy, silicon-chromium alloy, silicon-calcium aluminum alloy, manganese-silicon-aluminum alloy, silicon-calcium-barium alloy, silicon-aluminum-barium alloy, etc. |
| Classification according to the carbon content in ferroalloys | There are high carbon, medium carbon, low carbon, micro carbon, ultra-micro carbon and other varieties. |
| Classification according to production method | There are blast furnace ferroalloys, electric furnace ferroalloys, out-of-furnace ferroalloys (metal thermal process) ferroalloys, vacuum solid-state reduction ferroalloys, converter ferroalloys, electrolytic ferroalloys, etc. |
| Nitrided products | Nitrided products are produced by nitriding and other methods using ferromanganese or ferrochromium powder under high temperature conditions. Its main varieties include ferromanganese nitride, ferrochrome nitride, etc. |
| Oxide clumps | Oxide clumps that are easily reduced by iron can also be added directly to the molten steel as alloying agents. For example, molybdenum oxide clumps, etc. |
| Used as deoxidizer | The steelmaking process is a process in which molten iron is decarburized and removes harmful impurities such as phosphorus and sulfur by blowing oxygen or adding oxidants. As this process proceeds, although pig iron is made into steel, the [O] content in the molten steel increases. [O] generally exists in the form of [FeO] in molten steel. If the excess oxygen remaining in the steel is not removed, it will not be cast into a qualified steel billet, and steel with good mechanical properties will not be obtained. To this end, it is necessary to add some elements that have a stronger binding force with oxygen than iron, and whose oxides are easy to exclude from the molten steel and enter the slag, thereby removing [O] from the molten steel. This process is called deoxidation. The alloy used for deoxidation is called a deoxidizer. The binding strength of various elements in molten steel to oxygen, that is, the deoxidation ability, is in order from weak to strong as follows: chromium, manganese, carbon, silicon, vanadium, titanium, boron, aluminum, zirconium, and calcium. Therefore, iron alloys composed of silicon, manganese, aluminum, and calcium are commonly used for deoxidation in steelmaking. |
| Used as alloy agent | Alloy steel has different properties due to the different alloying elements it contains. The content of alloying elements in steel is adjusted by adding iron alloys. The iron alloy used to adjust the content of alloying elements in steel is called alloying agent. Commonly used alloying agents include iron alloys containing silicon, manganese, chromium, molybdenum, vanadium, tungsten, titanium, diamond, nickel, boron, niobium, zirconium and other elements. |
| Used as casting crystal nucleus inoculant | One of the measures to improve the properties of cast iron and steel is to change the solidification conditions of the casting. In order to change the solidification conditions, certain iron alloys are often added as crystal 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 castings. |
| Other uses | In the metallurgical and chemical industries, ferroalloys are increasingly used as media in mineral processing and as raw materials for the preparation of certain products and ultrapure substances (elements or compounds). |
