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Alloys neodymium

INTRA RARE EARTH BINARY ALLOYS NEODYMIUM-YTTRIUM... [Pg.85]

Gr. neos, new, and didymos, twin) In 1841, Mosander, extracted from cerite a new rose-colored oxide, which he believed contained a new element. He named the element didymium, as it was an inseparable twin brother of lanthanum. In 1885 von Welsbach separated didymium into two new elemental components, neodymia and praseodymia, by repeated fractionation of ammonium didymium nitrate. While the free metal is in misch metal, long known and used as a pyrophoric alloy for light flints, the element was not isolated in relatively pure form until 1925. Neodymium is present in misch metal to the extent of about 18%. It is present in the minerals monazite and bastnasite, which are principal sources of rare-earth metals. [Pg.181]

Sihca is reduced to siUcon at 1300—1400°C by hydrogen, carbon, and a variety of metallic elements. Gaseous siUcon monoxide is also formed. At pressures of >40 MPa (400 atm), in the presence of aluminum and aluminum haUdes, siUca can be converted to silane in high yields by reaction with hydrogen (15). SiUcon itself is not hydrogenated under these conditions. The formation of siUcon by reduction of siUca with carbon is important in the technical preparation of the element and its alloys and in the preparation of siUcon carbide in the electric furnace. Reduction with lithium and sodium occurs at 200—250°C, with the formation of metal oxide and siUcate. At 800—900°C, siUca is reduced by calcium, magnesium, and aluminum. Other metals reported to reduce siUca to the element include manganese, iron, niobium, uranium, lanthanum, cerium, and neodymium (16). [Pg.471]

Figure 16 shows the charge-discharge cycle characteristics of alloys in which part of the nickel component was replaced with cobalt. Misch metal (Mm), which is a mixture of rare earth elements such as lanthanum, cerium, praseodymium, and neodymium, was used in place of lanthanum. It was found that the partial replacement of nickel with cobalt and the substi-... [Pg.28]

The reduction diffusion process has also been used for the production of powders of the magnetic neodymium-iron-boron alloy (Nd15Fe77B8). The reaction involves use of a powder mix of neodymium oxide, iron, ferroboron and calcium. The reaction is conducted by heating the powder charge mixture at 1200 °C for 4 h under vacuum. Neodymium-iron-boron alloys are much more prone to oxidation than samarium-cobalt alloys and a proprietary leaching procedure is used for the separation of the alloy and calcium oxide. [Pg.384]

Several other useful modifications of calciothermic reduction have been successfully developed for the preparation of this neodymium-bearing magnetic alloy. One of these is reduction-extraction which involves the reduction of neodymium sesquioxide (Nd203) with calcium in a molten calcium chloride-sodium chloride salt bath at 750 °C and the simultaneous extraction of the reduced metal into a molten neodymium-zinc or neodymium-iron alloy pool. The neodymium-zinc alloy product is treated in vacuum to remove zinc and produce neodymium metal, while the neodymium-iron alloy is itself the end product of... [Pg.384]

Calcium is generated in situ for effecting reduction in another process in which elemental sodium is introduced in the charge mixture. The production of neodymium metal or of its alloys by the reduction of neodymium sesquioxide with sodium in the presence of calcium chloride is known as the NEOCHEM process. This process was developed at the General Motors Research Laboratories in the 1980s. The overall reaction pertinent to the process can be written as... [Pg.385]

Main uses. Calcium is important in steel production. It has a strong ability to alter the oxides and sulphides. Treatment with calcium modifies the melting points of inclusions which rapidly float out of the steel. Calcium is important in one method of producing a neodymium-iron alloy which is a neodymium ferro boron raw material (through, for instance, the reaction Nd203 + Ca + Fe — NdFe + byproducts). [Pg.348]

Z.S. Wronski, Rapid solidification of iron-neodymium-boron magnetic alloys, in rapid solidification technology-an engineering guide, In T.S. Srivatsan, Editor. (1993), Technomic Publishing, Lancaster, Basel, pp. 257-298. [Pg.75]

Neodymium is magnetic and is used in many of the most powerful magnets in the world. Some types of steel contain up to 18% neodymium as an alloy. It is also used as a color for TV tubes and as a tint for eyeglasses. [Pg.284]

Important is the use of light rare earth elonents for production of hard magnetic materials. Most prominent are alloys of samarium with cobalt in the atomic ratio 1 5 or 2 17. It may also be assumed that in further development of these materials on a larger scale that praseodymium, neodymium, lanthanum and also individual heavy rare ecu h elements will be used to achieve particular effects. Interesting is the development of magnetic bubble memories based on gadolinium-galliiimrgarnets. [Pg.14]

Mischmetall is a cheap alloy of the light lanthanides cerium, lanthanum, and neodymium are the main components. Benzaldehyde was added over a period of 14 h. [Pg.58]

Nd-Zn-Sb. The results of an X-ray phase analysis of 25 ternary neodymium-zinc-antimony alloys for the Sb-rich region (33.0-100.0 at.% of Sb) are presented in fig. 15 (Sologub and Salamakha, 1999). The alloys were obtained via a powder metallurgical reaction,... [Pg.67]

Fig. 1.26. Direct injection of a solution of neodymium (80%)-iron (20%) alloy. Conditions Supelco LC-18 DB column curve (A), gradient program at pH 4.5 from 0.05 mol/1 HIBA to 0.4 mol/1 HIBA in 10 min at flow rate of 1.0 ml/min modifier, 0.01 mol/1 1-octanesulfonate sample size, 50 pi sample dilution, 0.965 g per 100 ml. Curve (B), gradient program at pH 4.5 from 0.25 mol/1 HIBA to 0.5 mol/1 HIBA in 8 min at 1.0 ml/min modifier, 0.02 mol/1 1-octanesulfonate sample size, 50 pi sample dilution, 0.965 g per 100 ml and 5 ml/100 ml. Fig. 1.26. Direct injection of a solution of neodymium (80%)-iron (20%) alloy. Conditions Supelco LC-18 DB column curve (A), gradient program at pH 4.5 from 0.05 mol/1 HIBA to 0.4 mol/1 HIBA in 10 min at flow rate of 1.0 ml/min modifier, 0.01 mol/1 1-octanesulfonate sample size, 50 pi sample dilution, 0.965 g per 100 ml. Curve (B), gradient program at pH 4.5 from 0.25 mol/1 HIBA to 0.5 mol/1 HIBA in 8 min at 1.0 ml/min modifier, 0.02 mol/1 1-octanesulfonate sample size, 50 pi sample dilution, 0.965 g per 100 ml and 5 ml/100 ml.
Misch metal is an alloy of about 50% cerium, 25% lanthanum, 15% neodymium and 10% other rare earth metals. Uses include manufacture of a pyrophoric alloy with iron and deoxidizer in metallurgical applications, getter for removal of oxygen from vacuum tubes, high strength magnesium alloys. [Pg.897]

This is an alloy of about 50% cerium, 25% lanthanum, 15% neodymium and 10% other rare earth metals. [Pg.909]

MagnaCat A process for selectively removing metal-contaminated catalyst particles from an FCC reactor by magnetic separation. A high-strength magnet made from a neodymium-boron-iron alloy is used. Developed by the Ashland Oil, which sold it to MW Kellogg in 1997. [Pg.225]


See other pages where Alloys neodymium is mentioned: [Pg.597]    [Pg.11]    [Pg.79]    [Pg.89]    [Pg.597]    [Pg.11]    [Pg.79]    [Pg.89]    [Pg.190]    [Pg.402]    [Pg.27]    [Pg.386]    [Pg.420]    [Pg.423]    [Pg.11]    [Pg.18]    [Pg.620]    [Pg.382]    [Pg.402]    [Pg.960]    [Pg.1366]    [Pg.122]    [Pg.63]    [Pg.30]    [Pg.210]    [Pg.11]    [Pg.18]    [Pg.69]    [Pg.312]    [Pg.421]    [Pg.4235]    [Pg.1001]    [Pg.768]    [Pg.64]   
See also in sourсe #XX -- [ Pg.2 , Pg.357 ]




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Neodymium

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