Ferroniobium
Encyclopedia
Ferroniobium 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 ferroniobium can be purified by electron beam melting
or used as it is. For alloying with steel the ferroniobium is added to molten steel before casting. The largest producers of ferroniobium are the same as for niobium and are located in Brazil
and Canada
.
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
niobium
Niobium
Niobium or columbium , is a chemical element with the symbol Nb and atomic number 41. It's a soft, grey, ductile transition metal, which is often found in the pyrochlore mineral, the main commercial source for niobium, and columbite...
alloy, with a niobium content of 60-70%. It is the main source for niobium alloying of HSLA steel
HSLA steel
High-strength low-alloy steel is a type of alloy steel that provides better mechanical properties or greater resistance to corrosion than carbon steel. HSLA steels vary from other steels in that they are not made to meet a specific chemical composition but rather to specific mechanical properties...
and covers more than 80% of the world wide niobium production. The niobium is mined from pyrochlore
Pyrochlore
Pyrochlore 2Nb2O6 is a solid solution between the niobium end member , and the tantalum end member .-Occurrence:...
deposits and is subsequently transformed into the niobium pentoxide Nb2O5. This oxide is mixed with iron oxide
Iron oxide
Iron oxides are chemical compounds composed of iron and oxygen. All together, there are sixteen known iron oxides and oxyhydroxides.Iron oxides and oxide-hydroxides are widespread in nature, play an important role in many geological and biological processes, and are widely utilized by humans, e.g.,...
and aluminium
Aluminium
Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....
and is reduced
Redox
Redox reactions describe all chemical reactions in which atoms have their oxidation state changed....
in an aluminothermic reaction
Aluminothermic reaction
Aluminothermic reactions are exothermic chemical reactions using aluminium as the reducing agent at high temperature. The most prominent example is the thermite reaction between aluminium and iron oxides:-History:...
to niobium and iron. The ferroniobium can be purified by electron beam melting
Electron Beam Melting
Electron beam melting is a type of additive manufacturing for metal parts. It is often classified as a rapid manufacturing method. The technology manufactures parts by melting metal powder layer per layer with an electron beam in a high vacuum...
or used as it is. For alloying with steel the ferroniobium is added to molten steel before casting. The largest producers of ferroniobium are the same as for niobium and are located in Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
and Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
.