About 80% of the vanadium produced is used as a steel additive. Vanadium-steel alloys are very tough and are used for armour plate, axles, tools, piston rods, springs (Spring Steel Useful In Coil Spring, Comprises Tempered Martensite, Silicon, Carbon, Manganese, Chromium, Nickel, Molybdenum And Vanadium (2011)) and crankshafts.
Vanadium alloys are used in nuclear reactors because of vanadium’s low neutron-absorbing properties: Steel-Vanadium Alloy Cladding For Fuel Element (2019).
Vanadium(V) oxide is used as a pigment for ceramics (Vanadium-Bearing Ceramic Pigment (1958)), glass, and as a catalyst (Vanadium Pentoxide Catalyst And Method Of Preparation Thereof (1963)), for example in the contact process for producing sulphuric acid: Contact Sulphuric Acid Process (1928).
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All patent information has been obtained from Espacenet (European Patent Office).