Top PDF Method of forming magnetostrictive rods from rare earth-iron alloys

Method of forming magnetostrictive rods from rare earth iron alloys

Method of forming magnetostrictive rods from rare earth-iron alloys

Rods of magnetrostructive alloys of iron with rare earth elements are formed by flowing a body of rare earth- iron alloy in a crucible enclosed in a chamber maintained under an inert gas atmosphere, forcing such molten rare-earth-iron alloy into a hollow mold tube of refractory material positioned with its lower end portion within the molten body by means of a pressure differential between the chamber and mold tube and

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Preparations of rare earth iron alloys by thermite reduction

Preparations of rare earth-iron alloys by thermite reduction

conditions, to a temperature suf?cient to react the rare An improved method for the preparation of high earth and iron ?uoride mixture with the calcium to form purity rare earth-iron all[r]

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Method of increasing magnetostrictive response of rare earth iron alloy rods

Method of increasing magnetostrictive response of rare earth-iron alloy rods

This invention comprises a method of increasing the magnetostrictive response of rare earth iron (RFe) magnetostrictive alloy rods by a thermal-magnetic treatment. The rod is heated to a temperature above its Curie temperature, viz. from 400 rod is at that temperature, a magnetic field is directionally applied and maintained while the rod is cooled, at least below its Curie temperature.

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Thermal treatment for increasing magnetostrictive response of rare earth iron alloy rods

Thermal treatment for increasing magnetostrictive response of rare earth-iron alloy rods

The method of increasing the magnetostrictive response of a rod under compression formed from a gether with other rare earth metal selected from the stantially increased, and cooling sai[r]

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The Market For The "Not-So-Rare" Rare Earth Elements

The Market For The "Not-So-Rare" Rare Earth Elements

Despite the connotation suggested by its name, rare earth metals are actually not rare at all in terms of the quantity present in the earth’s crust. In fact, a number of these elements, such as cerium and yttrium are more abundant within the earth’s surface than are more commonly known metals such as gold, silver, iron or copper. What makes these rare earth elements scarce are the difficulties presented in mining and extracting these metals from its ore, and separating the metals into their individual elements -- processes that incur a great deal of research and development costs, high capital outlays, and require a highly trained and specialized work force. The reason that these processes are exceptionally difficult is attributed to the fact that, unlike the more familiar metals like gold and silver which can be found in high concentrations within the earth’s crust, the deposits of REEs are much less dense making it difficult and sometimes economically impractical to extract. Most deposits contain 1% or less of rare earth elements, with the world’s “richest veins” of deposits consisting of only 4% to 9% of the elements (Service, 2010b).
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Determination of Rare Earth Elements in Products of Chadormalu Iron Ore Concentrator Plant (Iran) from Beneficiation Point of View

Determination of Rare Earth Elements in Products of Chadormalu Iron Ore Concentrator Plant (Iran) from Beneficiation Point of View

never found as free metal in earth’s crust and their naturally occurring minerals consist of mixtures of various REEs and nonmetals [1]. REEs are found mainly in primary deposits associated with igneous intrusions and associated veins, dikes and pegmatites, and secondary deposit of beach, dune, alluvial placers and residual deposits. REEs bearing deposits minerals may occur as the main valuable component in well individualized deposits as well as potential by-products derived from other minerals, such as apatite. bastansite, monazite and xenotime are three most economically significant minerals to contain essential or significant REEs. Other commercial sources of REEs are apatite, REE bearing clays, allanite, zircon, euxenite and loparite [3].
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Hydrogen Generation by Ammonia Cracking
with Iron Metal Rare Earth Oxide Composite Catalyst

Hydrogen Generation by Ammonia Cracking with Iron Metal Rare Earth Oxide Composite Catalyst

results are ascribable to the high reactivity of atomic nitro- gen liberated form the metal nitride and indicate that one can regenerate ammonia readily by using the present catalyst sys- tem. Figure 8 shows a schematic model for hydrogen gen- eration method by cracking ammonia on the Fe–(Ce, Zr)O 2

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Magnetostrictive and Shape Memory Properties of Heusler Type Co2NiGa Alloys*

Magnetostrictive and Shape Memory Properties of Heusler Type Co2NiGa Alloys*

caused by the rearrangement of martensite variants. How- ever, in spite of their exceedingly huge strain, these alloys have serious weaknesses, that is, working to fiber or foilis very difficult because of the poor ductility or their low martensite transformation temperatures.

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Characterization and Iron Removal Treatment of Ion Adsorption Rare Earth Tailings in Southern China

Characterization and Iron Removal Treatment of Ion Adsorption Rare Earth Tailings in Southern China

mineral forms a grid mark pattern in the cross-section of magnetite grain. Figure 3 shows that it is hard to sepa- rate titanomagnetite from magnetite by sieving separation method. Figure 3(B) shows the image of the magne- tite associated kaolinite. In fact, Figure 1(D) and Figure 3(B) show that kaolinite and magnetite have the similar associated mineral structure. This associated structure results in the difficulty in the separation of magnetite from kaolinite.

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Effect of Rare Earth on M7C3 Eutectic Carbide in 13% Chromium Alloy Cast Iron

Effect of Rare Earth on M7C3 Eutectic Carbide in 13% Chromium Alloy Cast Iron

Expand enrolment in colleges, vocational schools, in remote areas; building inter-school regimes for seafarers after going to sea for 1 to 2 years to attract students; strengthen the dissemination of training models according to the pilot project on maritime officers training approved by the Ministry of Transport. Expand training facilities to be located in coastal areas, convenient for young people in coastal areas, and take advantage of the river environment to combine vocational training and the quality of seafarers. Rare earth are rare elements in the earth including 17 elements: scan, ytri, lanthanium ... These elements are
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Effect of Surface Coating on Electrochemical Properties of Rare Earth-Based AB5-type Hydrogen Storage Alloys

Effect of Surface Coating on Electrochemical Properties of Rare Earth-Based AB5-type Hydrogen Storage Alloys

For the surface microstructure characterization we used scanning electron microscopy, and the resulted images are shown in Fig.2. In Fig.2 (a), the surface of the untreated alloy is smooth. Some small particles from the mechanical ground step attached to the bulky alloy particles. In Fig.2 (b) a uniform Ni coating layer is found at the alloy surface, and on the edge the coating layer is thicker than the other area. EDS results show that Ni content obviously increases. For the Co-coated alloy powders (in Fig.2 (c)) flake-like coating layer is found at the alloy surface, and EDS results also show increase in Co content. Under the existence of amino acetic acid as complex agent, Ni- and Co-coating deposition on the alloy powders may follow the steps below: At first, the complex agent amino acetic acid was adsorbed onto the alloy surface owing to the complexation between oxygen element and rare earth element. And then the coated elements, Ni and Co come near to the –NH 2 and complexed with
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Rare earth doping of silicon

Rare earth doping of silicon

Sec.6.4.1 dealt with the investigation of the effects of im plant dosage and electrical characteristics of the silicon substrate with a view to addressing all four points highlighted above. It was found that, in the samples without fluorine, the n- type silicon produced the most intense luminescence at 1535nm, but that this was offset by deep levels appearing at 1650nm. Upon the introduction of fluorine, the energy levels of the erbium were subject to Stark splitting and the luminescence was enhanced by almost an order of magnitude. This coincided with a reduction in the deep level luminescence in the /i-type. The higher doses of both erbium and fluorine were found to produce the most intense luminescence at 1535nm. These findings agree with those of F.G. Ren et al.^. An explanation may be gained from the SIMS profiles, which indicate that erbium forms a complex with fluorine after heat treatment. As spreading resistance measurements did not demonstrate an increase in the donor activation of erbium upon the introduction of fluorine, it is not possible to state whether the effect of fluorine is either to oxidise any 2 + ions to the optically active 3+ state, or to reduce the number of nonradiative paths available to both the excitation and resultant luminescence. Thus, the investigation in Sec.6.4.2 was carried out, which dealt with the effect of tem perature and pump pow er and wavelength upon the erbium peak luminescence.
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Textures and Rare Earth Elements Composition of Banded Iron Formations (BIF) at Njweng Prospect, Mbalam Iron Ore District, Southern Cameroon

Textures and Rare Earth Elements Composition of Banded Iron Formations (BIF) at Njweng Prospect, Mbalam Iron Ore District, Southern Cameroon

ure 4(b)). The bands present similar textures as above, in addition to the alternating white to yellowish silica bands and light green to dark massive iron oxides bands. The common minerals that accompany the silicate in reflected light microscopy are martite, magnetite, goethite, and quartz (Figure 5(f)). In general, the weathering process that affected iron oxides in the various BIF facies is similar. They show variably hematitized magnetite (mar- titization), plus goethite weathering. The hematitization of magnetite may be incipient or nearly complete with only very tiny relicts of magnetite (Figures 5(c), 6(a) and (c)). The weathering affects preferentially the magnetite component. The BIF type shows alternating silica and laminae of martite/hematite layers, respectively ranging from 0.41 mm to 1 mm and from 0.51 mm to 0.88 mm for microbands with both sharp and gradational contacts. These layering are sometimes sandwiched by a thin goe- thite veneer (Figure 5(a)). Some iron oxide bands are porous, probably due to leaching of silica inclusions. A thin limonitic coating interstitial to the goethite grains is observed. No polished section of the enriched martite- goethite mineralization was done.
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Beneficiation Studies of a Rare Earth Ore from the Olserum Deposit

Beneficiation Studies of a Rare Earth Ore from the Olserum Deposit

The mineral grades of apatite, monazite, xenotime, silicate and others in the ore, concentrate and tailings are shown in Figure 7. It is seen that phosphates including monazite and xenotime were effectively enriched and silicates as the gangues were removed to the tailings. It is noted that apatite appears in the con- centrate at a high grade (65%). Separation of apatite from monazite and xeno- time could increase the REE grade of the concentrate. High intensity magnetic separation or acid leaching would be effective approaches for further processing of the concentrate.

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Preparation of rare earth metals

Preparation of rare earth metals

The same experiments using a tantalum or molybdenum vessel showed no detectable contamination of the rare earth metal& Work conducted by Daane 11 at the Ames Laboratory, on methods of we[r]

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Electropolishing the rare earth metals

Electropolishing the rare earth metals

Chemical oxidation is the principle method of etching a metal surface for microscopic examination and the rare earths were etched in this manner... At room temperature, the nitric acid-a[r]

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Recycling of Rare Earth Magnet Waste by Removing Rare Earth Oxide with Molten Fluoride

Recycling of Rare Earth Magnet Waste by Removing Rare Earth Oxide with Molten Fluoride

fi ne, and neither suspension of alloy in the fl ux nor suspension of fl ux in the alloy was observed. Oxygen concentration of alloy decreased from 5000 to 160 mass-ppm by charging fl ux of 1.5 times of equivalent amount for complete dissolution of oxide. Substitution of neodymium in the alloy and dysprosium in the fl ux was observed. The investigated process should be utilized for mildly contaminated waste such as a used (end- of-life) magnet because of simple process, energy saving and unlimited location. [doi:10.2320 / matertrans.M-M2013836]

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Magnetostrictive Properties of Galfenol Alloys Under Compressive Stress

Magnetostrictive Properties of Galfenol Alloys Under Compressive Stress

ature, much larger than common Fe and all other known 3d transition metal alloys. Rapid quenching increases the solu- bility of Ga in bcc Fe and thus the magnetostriction increases with increasing x for 0 . 17 < x ≤ 0 . 19. Our observed max- imum magnetostriction occurs in samples of ∼ 19% Ga in Fe that were rapidly quenched into water from 800 ◦ C. For

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Glass Forming Ability and Thermal Properties of the Mg Based Amorphous Alloys with Dual Rare Earth Elements Addition

Glass Forming Ability and Thermal Properties of the Mg Based Amorphous Alloys with Dual Rare Earth Elements Addition

investigation. The Cu-(Y, Nd) master alloy ingots were pre- alloyed by arc melting in an argon atmosphere. Then the Cu- (Y, Nd) alloys were melted together with Mg pieces by induction melting under argon atmosphere to obtain Mg 58 Cu 31 Y 11x Nd x alloy ingots. The alloy rods with 3 to

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Production method for making rare earth compounds

Production method for making rare earth compounds

A method of making a rare earth compound, such as a earth-transition metal permanent magnet compound, without the need for producing rare earth metal as a process step, comprises carbothermically reacting a rare earth oxide to form a rare earth carbide and heating the rare earth carbide, a compound-forming reactant (e.g. a transition metal and optional boron), and a carbide-forming element (e.g. a refractory metal) that forms a carbide that is more thermodynamically favorable than the rare earth carbide whereby the rare earth compound (e.g. Nd.sub.2 Fe.sub.14 B or LaNi.sub.5) and a carbide of the carbide-forming element are formed.
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