Refractory Niobium

Annealing Procedure

Heat thoroughly at 1200 C in inert gas or vacuum at pressure below 1 x 10 -4 Torr. For stress relieving, 800 C is the recommended temperature.

Applications

The largest user of niobium was and is the nuclear power industry, however the alloy has successfully been employed in a variety of other applications including jet engine components. It is commonly used as an alloying element in many of the high temperature superalloys.

Cold Workability

Niobium possesses excellent cold working properties and can be forged rolled or swaged from ingot at room temperature.

Forgeability

Niobium can be cold forged from ingot at room temperature.

Formability

Niobium, because of its low work hardening rate can readily be formed, spun and stamped, although great care must be taken with lubrication.

Heat Treatability

See annealing.

Machinability

In general, niobium has a strong tendency to gall. It is recommended to use high speed tooling with good lubrication. The material turns very similarly to soft copper or lead.

Principle Design Features

Niobium (also occasionally called Columbium) is a relatively light metal that maintains high mechanical properties at extreme temperatures. Niobium is extremely similar in many ways to Tantalum. They were discovered almost simultaneously and many metallurgists feel that many applications employing tantalum could be more cost effectively dealt with by using niobium.

Weldability

TIG welding is the preferred method for niobium, with a few notable modifications. The weld pool must be covered with inert gas both on the face and back of the weld area.