Niobium combines many useful physical, mechanical and technological properties that determine its application in different industries - from metallurgy to nuclear physics. This page deals with the description of this metal: physical and chemical properties, applications, grades and types of products.
General information
Niobium - atomic number - 41, atomic weight - 92.90. It is a glossy silvery-gray refractory metal. Its density is 8.57 g/cm3, melting temperature tmelt. = 2468 °С, boiling temperature tboil. = 4742 °С. This metal has a good durability, hardness and plasticity.
The described chemical element belongs to rare refractory metals. It is always present in ores together with tantalum. The main minerals are columbite-tantalite, loparite and pyrochlore.
Discovery
Niobium was discovered by English scientist Charles Hatchett in 1801. Firstly this metal was named “columbium”. By 1844 it was considered that Ta and Nb is the same element. Pure Nb was obtained at the end of the 19th century by French chemist Henri Moissan by reducing niobium oxide with carbon in an electric furnace.
Both pure niobium without any alloying elements and alloys on its basis are used in industry.
Nb1 - high-purity niobium with Nb content 99.84%; supplied in form of ingots.
NbSh00, NbSh0, NbSh1 - pure niobium in form of billets, Nb content is 99.77%, 99.56% and 99.37% correspondingly.
NbP, NbP-а, NbP-b - pure niobium in form of powder.
VN1, VN2, VN2AE - niobium-molybdenum or molybdenum-zirconium alloys. The first grade contains 3.8-52% of Mo, the second one - 3.5-4.7% of Mo and 0.5-0.9% of Zr.
NbTs, NbTsC, Nb5W2MoZr, Nb10W2MoZr, Nb10W5MoZrC - group of niobium-based alloys that include different amounts of tungsten, molybdenum, zirconium and carbon.
Advantages/drawbacks
Advantages:
has a high melting temperature;
corrosive-resistant in many chemically aggressive media;
has good technological and mechanical properties - good plasticity, weldability and durability.
Drawbacks:
relatively low content in the earth core;
rather expensive (cheaper than tantalum, but more expensive than tungsten or molybdenum).
Niobium applications
This metal has the following applications:
chemical and nuclear industry;
metallurgy;
electronics;
nuclear physics;
aircraft engineering.
High durability and good corrosion stability (including under high temperatures) allow using niobium as a construction material. Such application is typical for producing components of aircraft, pipes and containers for transporting and storing liquid metals and capsules for radioactive heat-releasing elements.
Nb is a common alloying element that allows improving the properties of steels and alloys that contain this element. Nb makes the alloy materials durable, corrosive-resistant and refractory.
The considered metal is also applied in producing condensers that serve as important elements in electronics. Niobium condensers are worse than tantalum ones, but they are much cheaper.
Nb3Sn, Nb3Ge, NbN and NbTi compounds are used for making supercondensers. Such properties are highly-demanded in scientific equipment used for physical experiments.
Niobium products
Contemporary industry offers a full range of standard blanks actively used in different spheres. Rolled products include niobium wire, rod and pipe. Flat products are represented by niobium foil and strip, sheets, flat bars. Primary raw materials include niobium powder that is the main component of the chain of making products of this metal.