Niobium, also known as columbium has a melting point of 2468°C and density of 8.57 gm/cc. It has many properties that make it an excellent candidate for fabricated parts that must be made of a refractory metal. Its high melting point warrants its use at temperatures above the maximum service temperatures of the iron base, nickel base, and cobalt base metals. It has excellent ductility and fabricability. Pure niobium has a recrystallization temperature range of 982° to 1093°C.

Niobium was used as an alloy for many years. Nb/1%Zr was, and still is, used in nuclear reactors as the tubing for the fuel pellets. As C-103 alloy, it has been used for rocket nozzles and exhaust nozzles for jet engines and rockets. Niobium mill products are used in the fabrication of corrosion resistant process equipment including reaction vessels, columns, bayonet heaters, shell and tube heat exchangers, U-tubes, thermowells, spargers, rupture diaphragms, and orifices.

Niobium metal powders have found electrolytic capacitor applications recently as an alternative to Tantalum. Capacitor grade niobium powder has been prepared by hydrogen reduction followed by magnesiothermic reduction of the niobium pentoxide.

Key features
• Process technology developed using indigenous raw materials
• Economically viable process
• Good quality products

Current Status
Process technology is being developed at C-MET, Hyderabad for preparation of high purity Niobium metal starting from Tantalite-Columbite ore under a project sponsored by VSSC (ISRO, Govt.of India), Trivandrum. Already high purity Nb2O5 has been developed and converted to Nb metal.

Specifications
Chemical Analysis of Niobium Metal (BEFORE EB MELTING)

Specifications

Sl. No	Elements in Cd matrix	Concentration in ppm
1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.	Al Fe Cr Ni Si Mn W Zr Ti Ta O	11600 800 140 120 < 10 < 10 < 10 < 10 < 10 50 3100

EB Refined Niobium Ingot