General Information
niobium chemical element
Niobium (pronounced | n? '? b? ? m |) (Greek mythology: Niobe, daughter of Tantalus), or columbium (| k? 'l? mb? ? m |), is the chemical element with the symbol Nb and the atomic number 4. A rare, soft, grey, ductile transition metal, niobium is found in the minerals pyrochlore, the main commercial source for niobium, and columbite.has physical and chemical properties similar to those of the element tantalum, and the two are therefore difficult to distinguish . The English chemist Charles Hatchett reported a new element similar to tantalum in 1801, and named it columbium. In 1809, the English chemist William Hyde Wollaston wrongly concluded that tantalum and columbium were identical. The German chemist Heinrich Rose determined in 1846 that tantalum ores contain a second element, which he named niobium. In 1864 and 1865, a series of scientific findings clarified that niobium and columbium were the same element (as distinguished from tantalum), and for a century both names were used interchangeably. The name of the element was officially adopted as niobium in 1949.was not until the early 20th century that niobium was first used commercially. Brazil is the leading producer of niobium and ferroniobium, an alloy of niobium and iron. Niobium is used mostly in alloys, the largest part in special steel such as that used in gas pipelines. Although alloys contain only a maximum of 0.1%, that small percentage of Niobium improves the strength of the steel. The temperature stability of niobium-containing superalloys is important for its use in jet engines and rocket engines. Niobium is used in various superconducting materials. These superconducting alloys, also containing titanium and tin, are widely used in the superconducting magnets of MRI scanners. Other applications of niobium include its use in welding, nuclear industries, electronics, optics, numismatics and jewellery. In the last two applications, niobium's low toxicity and ability to be colored by anodisation are particular advantages.
History
was discovered by the English chemist Charles Hatchett in 1801. He found a new element in a mineral sample that had been sent to England from Massachusetts in 1734 by a John Winthrop, and named the mineral columbite and the new element columbium after Columbia, the poetical name for America. The columbium discovered by Hatchett was probably a mixture of the new element with tantalum., There was considerable confusion over the difference between columbium (niobium) and the closely related tantalum. In 1809, the English chemist William Hyde Wollaston compared the oxides derived from both columbium-columbite, with a density 5.918 g/c...
