ferro tungsten, a specialized alloy of iron and tungsten, is commonly used as an additive in steel melts. Its high melting point, low vapor pressure and superior tensile strength make it useful for aerospace functions and welding. It is also a good conductor of electricity, and thus, has found use in electron microscopes, IC chips and other electrical applications.
Introduction: Tungsten is a heavy metal, with a very high melting point (3422°C/6192°F), low vapor pressure and very high thermal creep resistance. It is also a very tough metal, highly resistant to corrosion and can be attacked only by mineral acids.
Tungsten is widely available in the earth and can be extracted from a variety of minerals, including wolframite, scheelite, ferberite and hubnerite. The tungsten trioxide in these compounds can be reduced either carbothermically by electric arc furnaces, or metallothermically by silicon and/or aluminum.
Methods for Smelting Tungsten
The smelting of ferro tungsten is carried out by a special-purpose three-phase electric arc furnace. The smelting process consists of the following steps: preheating, adding calcioschellite preparation concentrate, refining, digging, adding pitch coke, leaning slag, deslagging and cooling the product and packaging, etc.
Formulation of Furnace Burden:
The furnace burden is made up of 70 to 80 percent of white tungsten concentrate, 4% to 9% of FeO, 3% to 7% of SiO2, 4% to 9% of FeSi and 1% to 5% of Fe. The components are fully and uniformly mixed.