Views: 0 Author: Site Editor Publish Time: 2022-12-12 Origin: Site
Ferroalloys are various ferrous alloys that contain high proportions of one or more other elements such as manganese (Mn),aluminum (Al),or silicon (Si).They are used in the production of steels and alloys.These alloys impart unique qualities to steel and cast iron or play an important role in the production process and are therefore closely associated with the steel industry,the major consumer of ferroalloys.The main producers of ferroalloys in 2014 were China,South Africa,India,Russia and Kazakhstan,accounting for 84% of world production.World ferroalloy production was estimated at 52.8 million tons in 2015.
The main ferroalloys are:
FeB-Iron Boron-12-20% boron,max.Up to 3% Silicon 2% Aluminum 1% Carbon.
FeMo-Iron Molybdenum-Minimal. 60% molybdenum 1% silicon 0.5% copper.
FeNi-ferronickel (and nickel pig iron).
FeSi-Ferrosilicon – 15–90% Si.
FeSiMg-Iron Magnesium (4% to 25% Magnesium),also known as nodularizer.
FeTi-Ferro Titanium-10..30–65..75% Ti,max.5–6.5% Aluminum 1-4% Silicon max.
Production,according to the process
Ferroalloys are generally produced by two methods:in blast furnaces or in electric arc furnaces.Blast furnace production continued to decline during the 20th century,while electric arc production continued to increase.Today,blast furnaces still efficiently produce ferromanganese,but even here electric arc furnaces are gaining in popularity.More commonly,ferroalloys are produced by carbothermal reactions,involving the reduction of oxides with carbon (such as coke) in the presence of iron. Some ferroalloys are produced by adding elements to molten iron.Somme ferroalloys can also be produced by the direct reduction process. For example,Japan uses the Krupp-Wren process to produce ferronickel.
Production and consumption of ferroalloys
The world's main chromite producers in 2014 were South Africa (12 tons),Kazakhstan (3.7 tons),India (3.5 tons) and Turkey (2.6 tons).Most chromite ore is smelted in electric arc furnaces to produce ferrochrome for the metallurgical industry.The world's major producers of ferrochrome in 2014 were China (4.5 metric tons),South Africa (3.6 metric tons),Kazakhstan (1.2 metric tons) and India (0.9 metric tons).Most of the 11.7 Mt of ferrochromium produced globally is used to make stainless steel,totaling 41.7 Mt in 2014.
Ferromanganese and silicomanganese,two ferromanganese alloys,are key raw materials for steelmaking.China is the world's leading producer of ferromanganese (2.7 metric tons),much more than the next three largest producers-Brazil (0.34 metric tons),South Africa (0.61 metric tons) and Ukraine (0.38 metric tons) combined).
The main producers of ferromolybdenum are (16,918 tons),China (40,000 tons) and the United States (in 2008, the United States accounted for 78% of the world's molybdenite production.Canada,Mexico and Peru accounted for the remainder.Molybdenum concentrates go through Roasting forms molybdenum oxide,which can be converted into ferromolybdenum,molybdenum chemicals,or molybdenum metal.Although the United States was the world's second largest producer of molybdenum in 2008,more than 70% of ferromolybdenum demand in 2008 was imported,mainly for the steel industry (83% of ferromolybdenum consumed).