About Tantalum
Tantalum is a rare, hard, blue-gray, lustrous transition metal that is highly corrosion-resistant. It is part of the refractory metals group, which are widely used as minor components in alloys. The chemical inertness of tantalum makes it a valuable substance for laboratory equipment, and as a substitute for platinum. Its main use today is in tantalum capacitors in electronic equipment such as mobile phones, DVD players, video game systems and computers. Tantalum, always together with the chemically similar niobium, occurs in the mineral groups tantalite, columbite and coltan (the latter is a mix of columbite and tantalite, though not recognised as a separate mineral species). Tantalum is considered a technology-critical element by the European Commission. As a metal powder, the primary application of tantalum is in the manufacture of electronic parts, especially capacitors and some high-power resistors. Tantalum electrolytic capacitors exploit the propensity of tantalum to form a surface layer of protective oxide, using tantalum powder, pressed into a pellet shape, as one "plate" of the condenser, the dielectric oxide, and the other "plate" as an electrolytic solution or conductive solid. Since the dielectric layer can be very thin (thinner than the equivalent layer in an aluminium electrolytic capacitor, for instance), a small volume of high capacitance can be achieved. Tantalum is also used to manufacture a variety of alloys with a high melting point, strength, and ductility.