Ferro niobium is an important iron niobium alloy, with a niobium content of 60-70%. It is the main source for niobium alloying of HSLA steel and covers more than 80% of the world wide niobium production. The niobium is mined from pyrochlore deposits and is subsequently transformed into the niobium pentoxide Nb2O5. This oxide is mixed with iron oxide and aluminium and is reduced in an aluminothermic reaction to niobium and iron. The ferro niobium can be purified by electron beam melting or used as it is. For alloying with steel the ferro niobium is added to molten steel before casting.The largest producers of ferro niobium are the same as for niobium and are located in Brazil and Canada.
Ferro Niobium imparts a doubling of strength and toughness as well as weight reduction due to its grain refining attributes in carbon and HSLA steels. The main first use industries for Ferro Niobium are in carbon pipelines, construction and automobiles. It is also added to stainless steel to stop embrittlement after welding.
from:Rare Metals
No comments:
Post a Comment