Brief introduction of niobium tube:
Niobium is a steel gray metal. Niobium and tantalum have approximate nature. Niobium is mainly used in metallurgy industry, atomic energy and aerospace industry, petroleum chemical industry, electronic industry and other departments. More than 80% of niobium is used in the production of steel. The

price of niobium

keep stable at present.

Niobium tube

is grouped into seamless tube and seamed niobium tube.
Material: RO4200-1， RO4210-2
Diameter:　φ1.0-100mm
Thickness:　0.2-5.0mm
Length:　　200mm-9000mm
Standard: As per ASTM B394-98
Purity: ≧99.9％　 or　 99.95％

Properties of niobium tube:
Niobium tube has such properties as high melting point, good corrosion resistance and good processing properties.
Applications of niobium tube:
Niobium tube is mainly used for spinning of thin tube blank, thermocouple cannula and other special purposes.
 
Table.1 Chemical composition:

chemistry%
designation	chief component		impurities maximum
	Nb	Fe	Si	Ni	W	Mo	Ti	Ta	O	C	H	N
Nb1	Remainder	0.004	0.003	0.002	0.004	0.004	0.002	0.07	0.01	0.004	0.0012	0.002
Nb2	Remainder	0.005	0.005	0.005	0.01	0.01	0.004	0.1	0.015	0.01	0.0015	0.01

 
　
Table 2. Mechanical requirements (annealed condition)

Grade	Tensile strength　 δbpsi (MPa)， ≥	Yield strength　　δ0.2， psi (MPa)，≥	Elongation in 1"/2" gage length， ％， ≥
RO4200-1 RO4210-2	18000 (125)	10500 (73)	25
Special requirements to be agreed on by the supplier and buyer of negotiations