Niobium (Columbium) Refractory Metals

Niobium is a chemical element with the symbol Nb and atomic number 41. Niobium is a light grey, crystalline with a melting point of 2468°C which characterizes it as a refractory metal. With its myriad of properties, Niobium is an excellent contender for fabricated parts.


Due to its low capture cross section for thermal neutrons, Niobium has application in the nuclear industry. Niobium can be electrically heated and anodized to a wide variety of colors and may be used as a hypoallergenic alternative to Nickel making it a very attractive material for use in the jewelry industry. Niobium is added to Iron or Nickel to produce alloys found in the aerospace, medical and electronics industries.


Niobium becomes a superconductor at cryogenic temperatures and has the greatest magnetic penetration depth of any element. Niobium has the lowest melting point of all the traditional refractory metals. Its chemical properties are very similar to those of Tantalum which appear directly below Niobium in the Periodic Table, however, the corrosion resistance of Niobium is not as robust as Tantalum.


Niobium was called Columbium (symbol Cb) in the United States for approximately one hundred years, although in Europe it was referenced as Niobium. In 1949, the International Union of Pure and Applied Chemistry officially adopted Niobium as the element’s name worldwide. Today, one can still find metallurgists and metal societies that still refer to Niobium as Columbium.


When compared with other refractory metals, Niobium possesses the:

  • Highest Thermal Expansion
  • Lowest Melting Point
  • Lowest Modulus of Elasticity
  • Lowest Thermal Conductivity


  • Symbol: Nb
  • Category: Reactive Transition Metal, Group 5
  • Atomic Number: 41
  • Crystal Structure: Body-centered Cubic
  • Density: 8.60 g/cm3
  • Discovered: 1801

Niobium Forms and Sizes

EFINEA is a leading supplier of refractory metals and alloys. We have supplied specialty metals and alloys to high technology industries since 1965.  We have a large inventory of refractory metals and alloys, and distribute Niobium products sourced from manufacturers and leading mills who produce them.

niobium forms

Niobium Coil, Plate, Round Bar, Rod, Sheet, Strip & Wire

We are a distributor of Niobium from leading mills. We supply Niobium coil, plate, round bar, rod, sheet, strip and wire in a variety of sizes.

Niobium Characteristics and Properties

The chemical properties of Niobium are very similar to those of Tantalum. View the specifications and the typical  mechanical, physical, and chemical properties this metal exhibits.

niobium mechanical physical properties specifications chemistry
  • Good Corrosion Resistance
  • Greatest Magnetic Penetration Depth of Any Element
  • Highly Ductile and Comparatively Soft
  • Physiologically Inert and Hypoallergenic
  • Superconductivity at Cryogenic Temperatures

Machining Niobium

Machining Guide for Niobium Refractory MetalNiobium is to some extent difficult to machine and has a tendency to gall, tear and weld to the cutting tool.  Light machine oils and lubricants with additives designed to prevent cold welding and sticking are suitable machining lubricants. Bronze is a good tooling material to use to avoid the cold-welding problems this metal exhibits but high-speed steel and carbide tools may also be employed, however there is a tendency to gall with carbide tools. Since Niobium has high ductility, it can be processed by bending, deep drawing, pressing, stamping, etc.

Niobium Applications

Niobium Refractory Metal Applications

Niobium’s (Columbium) combination of strength, melting point, resistance to chemical attack makes this metal applicable for numerous applications in a variety of industries.  Listed below are examples.

  • Capacitors
  • Nuclear Reactors
  • Optics
  • Shell and Tube Heat Exchangers
  • Steel Additive
  • Superconducting Magnets
  • Thermowells

For more information on technology, engineering and advanced materials applications, you can visit the IEEE  website, one of the largest technical professional organizations worldwide.

EFINEA is the leading worldwide supplier of specialty metals and alloys for customers who require materials certified to ASTM standards, cost efficient pricing and an unmatched selection of inventory that is ready to ship.  Select from our high-quality refractory, controlled expansion, soft magnetic alloys or electronic nickels in various forms, tempers and conditions.