Non-ferrous metals are alloys or metals that do not contain any appreciable amounts of iron. All pure metals are non-ferrous elements, except for iron (Fe), which is also called ferrite from the Latin "ferrum," meaning "iron." Non-ferrous metals tend to be more expensive than ferrous metals but are used for their desirable properties, including light weight (aluminium), high conductivity (copper), non magnetic properties or resistance to corrosion (zinc). Some non-ferrous materials are used in the iron and steel industries, such as bauxite, which is used for flux in blast furnaces. Other non-ferrous metals, including chromite, pyrolusite and wolframite, are used to make ferrous alloys. However, many non-ferrous metals have low melting points, making them less suitable for applications at high temperatures.
Tantalum is a chemical element with the symbol Ta and atomic number 73. Previously known as tantalium, it is named after Tantalus, a villain from Greek mythology. 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.
Niobium, or columbium, is a chemical element with the chemical symbol Nb (formerly Cb) and atomic number 41. Niobium is a light grey, crystalline, and ductile transition metal. Pure niobium has a Mohs hardness rating similar to pure titanium, and it has similar ductility to iron. Niobium oxidizes in Earth's atmosphere very slowly, hence its application in jewelry as a hypoallergenic alternative to nickel. Niobium is often found in the minerals pyrochlore and columbite, hence the former name "columbium". Its name comes from Greek mythology: Niobe, daughter of Tantalus, the namesake of tantalum. The name reflects the great similarity between the two elements in their physical and chemical properties, which makes them difficult to distinguish.
Molybdenum is a chemical element with the symbol Mo and atomic number 42 which is located in period 5 and group 6. The name is from Neo-Latin molybdaenum, which is based on Ancient Greek Μόλυβδος molybdos, meaning lead, since its ores were confused with lead ores. Molybdenum minerals have been known throughout history, but the element was discovered (in the sense of differentiating it as a new entity from the mineral salts of other metals) in 1778 by Carl Wilhelm Scheele. The metal was first isolated in 1781 by Peter Jacob Hjelm.
Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a new element in 1781 and first isolated as a metal in 1783. Its important ores include scheelite and wolframite, the latter lending the element its alternate name.
Titanium is a chemical element with the symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resistant to corrosion in sea water, aqua regia, and chlorine.
Zirconium is a chemical element with the symbol Zr and atomic number 40. The name zirconium is taken from the name of the mineral zircon. The word is related to Persian zargun (zircon; zar-gun, "gold-like" or "as gold"), the most important source of zirconium. It is a lustrous, grey-white, strong transition metal that closely resembles hafnium and, to a lesser extent, titanium. Zirconium is mainly used as a refractory and opacifier, although small amounts are used as an alloying agent for its strong resistance to corrosion. Zirconium forms a variety of inorganic and organometallic compounds such as zirconium dioxide and zirconocene dichloride, respectively. Five isotopes occur naturally, four of which are stable. Zirconium compounds have no known biological role.