Ferroniobium can be used as alloy additives.
The main usage of ferrovanadium is to make alloy steel. Ferrovanadium is also used widely in make spring steel, bearing steel and cast iron.
Ferrotungsten is used as additive for tungsten element in steel-making. Tungsten in steel can combine with other element to complex carbonization. Then the rigidity in high temperature, abrasion resistance and intension for striking are improved.
Ferrotitanium is the deoxidizer in steel-making, and it is also the additive for eliminating the gas and alloy element.