This is an audio version of the Wikipedia Article:
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00:02:17 1 History
00:05:25 1.1 Naming the element
00:06:44 2 Characteristics
00:06:53 2.1 Physical
00:08:18 2.2 Chemical
00:09:23 2.3 Isotopes
00:11:00 2.4 Occurrence
00:13:36 3 Production
00:17:08 4 Compounds
00:18:10 4.1 Oxides and sulfides
00:19:20 4.2 Halides
00:21:07 4.3 Nitrides and carbides
00:21:35 5 Applications
00:22:04 5.1 Steel production
00:23:00 5.2 Superalloys
00:24:10 5.3 Niobium-based alloys
00:26:29 5.4 Superconducting magnets
00:27:24 5.4.1 Other superconductors
00:28:32 5.5 Other uses
00:28:40 5.5.1 Electroceramics
00:29:20 5.5.2 Hypoallergenic applications: medicine and jewelry
00:30:02 5.5.3 Numismatics
00:31:16 5.5.4 Other
00:32:11 6 Precautions
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"There is only one good, knowledge, and one evil, ignorance."
- Socrates
SUMMARY
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Niobium, formerly known as columbium, is a chemical element with symbol Nb (formerly Cb) and atomic number 41. It is a soft, grey, crystalline, ductile transition metal, often found in the minerals pyrochlore and columbite, hence the former name "columbium". Its name comes from Greek mythology, specifically Niobe, who was the daughter of Tantalus, the namesake of tantalum. The name reflects the great similarity between the two elements in their physical and chemical properties, making them 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. Niobium was officially adopted as the name of the element in 1949, but the name columbium remains in current use in metallurgy in the United States.
It 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 60–70% niobium with iron. Niobium is used mostly in alloys, the largest part in special steel such as that used in gas pipelines. Although these alloys contain a maximum of 0.1%, the small percentage of niobium enhances the strength of the steel. The temperature stability of niobium-containing superalloys is important for its use in jet 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 welding, nuclear industries, electronics, optics, numismatics, and jewelry. In the last two applications, the low toxicity and iridescence produced by anodization are highly desired properties.
