Niobium and tantalum are often associated, but the content of niobium in the crust is about 2.4 × 10-3%, 10 times as much as tantalum, mainly in the form of niobite. "Generally, niobium has a higher corrosion resistance than titanium and zirconium, but slightly lower than tantalum. Due to its lower price than tantalum, niobium can be used to replace the more expensive tantalum in some corrosive media.". At the same time, the relative density of niobium is only about 1/2 that of tantalum. With the same component size, the amount of niobium used is only about 1/2 that of tantalum, which can reduce costs.

Like tantalum, niobium becomes a passivation type corrosion resistant metal by forming a dense oxide film on its surface, so the corrosion resistance of niobium is somewhat similar to that of tantalum. "Niobium is mainly used in strong acid media with low temperatures and strong reducibility, but it is not resistant to corrosion in hydrofluoric acid, hot concentrated sulfuric acid, sodium hydroxide, potassium hydroxide, and other media. The corrosion rate in hot concentrated hydrochloric acid and hot concentrated phosphoric acid is also high. When using niobium in these media, care should be taken.".

The boiling point of niobium is; 4927 ℃, melting point: 2468 ℃, belonging to refractory metal. Niobium can be formed at a moderate temperature of 350~400 ℃, formed at a high temperature of 950~1000 ℃, and fully annealed at about 1200 ℃. "Niobium begins to oxidize in air from 230 ℃ to 300 ℃, where it strongly oxidizes. When the temperature is higher than 400 ℃, the oxide film breaks down and falls off, greatly accelerating the oxidation rate.". Niobium begins nitriding in air at 600 ℃. In a hydrogen containing medium, niobium can absorb hydrogen at 250 ℃ to 950 ℃. Therefore, welding and heat treatment of niobium should be carried out in vacuum or under inert gas protection, that is, thermal processes above 300 ℃ should be carried out under vacuum or inert gas or high-temperature coating protection. When niobium equipment and containers are exposed to the atmosphere, the application temperature should generally not exceed 230 ℃. Only when it is ensured that they are not in contact with the atmosphere, can the temperature be appropriately increased. The protection method of niobium during welding is the same as that of tantalum using high purity inert gas, and when the temperature is above 230 ℃, it should also be placed under inert gas protection. It is best to stop supplying inert gas after cooling the niobium weldment to 200 ℃.

Niobium materials have been used in pressure vessels to some extent, but there is no formal standard for niobium vessels. Pure niobium is mainly used in pressure vessels, and adding about 1% zirconium can improve strength, but slightly reduce corrosion resistance and plasticity.