Vanadium - the secret hero of metallurgy

 Vanadium - the secret hero of metallurgy

Vanadium (V) is the lesser known among the lighter transition metals, located between the popular titanium (Ti) and chromium (Cr) it kind of gets overshadowed. The importance of vanadium, however can not be overstated. It plays a huge role in improving hardenability, tensile strength, tribological wear resistance and hardness of steels.

Pure V crystals.

An ampoule of V crystals.

Pure vanadium metal is widely available in three forms. Most importantly, in an alloy called ferrovanadium, containing ~80% of V with the rest being Fe and other metals. In such form it is used in metallurgy, as it's not worth it to purify it further when the plan is to mix it with iron anyways.

The two other forms are pure metallic bars/ingots, often in interesting swirly shapes and dendritic crystals. The latter ones are the more attracttive though and are pictured above.

It's worth noting that vanadium is unexpectedly reactive on air and while the colors look pretty at first, it is eventually going to turn dull gray/black. After that, they will need a nitric acid bath to restore the shine. Samples of vanadium are sometimes sold ampouled under argon to protect them from oxidation.

Cr-V steel bits.

Cr-V steel EDC tool.

Vanadium is what makes the production of different kinds of tool steels possible. Even in small amounts, it helps a knife keep it's sharpness longer and a screwdriver keep it's shape instead of stripping. Vanadium's influence is not limited to changing the properties of solid solutions. During cooling of steel, it can form vanadium carbides which are essentially ceramics and harden the material even further. All sorts of wrenches, bits, sockets, files, pliers and cutters are proudly announcing their composition with "Cr-V" written on the metal, at the same time pointing in the direction of another crucial alloying metal - aforementioned chromium.

A piece of vanadinite mineral.

A sample of vanadium I find particularly interesting is a piece of vanadinite mineral I got from China. It's a rare mineral that forms beautiful brownish-orange crystals. The color might not be that visible on my specimen due to the matrix it's contained in. Vanadinite is actually a mineral of lead - it's a lead chlorovanadate with the formula Pb5(Cl[VO4]3).