Vanadium

Vanadium resists acid and alkali corrosion and salt water.   It is strong and has a low fission neutron cross-section (cannot be penetrated easily by radiation), making it useful in nuclear reactors.   The largest use of vanadium is as a steel additive to make it rust resistant, and in springs, and high speed tool steels.   It is also used as a carbide stabilizer in steel manufacture.   Vanadium foil is used to bond titanium to steel.   Vanadium pentoxide is used in ceramics, as a catalyst, and in superconductive magnets. ^{Lide 4-32}

Vanadium was discovered by del Rio in 1801, but incorrectly thought by others to be impure chromium.   It was rediscovered in in 1830 by Sefstrom and isolated by Roscoe in 1867 by reducing the chloride with hydrogen.   Purity of 99.3 to 99.8 % was obtained in 1927.   It is produced commercially by reducing vanadium trichloride with magnesium or with magnesium-sodium mixtures.   A more popular method is the reduction of V₂O₅ with calcium under pressure, a variation of a process invented by McKenchnie and Seybolt.   Vanadium is found in about 63 minerals, such as carnotite, roscoelite, vanadinite, and patronite.   It also is found in phosphate rock, iron ores, and petroleum. ^{Lide 4-32}