EP0272250A1 - Verfahren zur Herstellung von Neodymlegierungen - Google Patents

Verfahren zur Herstellung von Neodymlegierungen Download PDF

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Publication number
EP0272250A1
EP0272250A1 EP88100014A EP88100014A EP0272250A1 EP 0272250 A1 EP0272250 A1 EP 0272250A1 EP 88100014 A EP88100014 A EP 88100014A EP 88100014 A EP88100014 A EP 88100014A EP 0272250 A1 EP0272250 A1 EP 0272250A1
Authority
EP
European Patent Office
Prior art keywords
neodymium
iron
calcium
alloys
calcium chloride
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP88100014A
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English (en)
French (fr)
Other versions
EP0272250B1 (de
Inventor
Françoise Seon
Bernard Boudot
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Rhodia Chimie SAS
Original Assignee
Rhone Poulenc Chimie SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from FR8311139A external-priority patent/FR2548687B1/fr
Application filed by Rhone Poulenc Chimie SA filed Critical Rhone Poulenc Chimie SA
Priority to AT88100014T priority Critical patent/ATE81156T1/de
Publication of EP0272250A1 publication Critical patent/EP0272250A1/de
Application granted granted Critical
Publication of EP0272250B1 publication Critical patent/EP0272250B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B5/00—General methods of reducing to metals
    • C22B5/02—Dry methods smelting of sulfides or formation of mattes
    • C22B5/04—Dry methods smelting of sulfides or formation of mattes by aluminium, other metals or silicon
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C28/00—Alloys based on a metal not provided for in groups C22C5/00 - C22C27/00
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B59/00—Obtaining rare earth metals

Definitions

  • the present invention relates to neodymium alloys and their manufacturing process.
  • ceric rare earth metals a designation which includes lanthanum, cerium, praseodymium and neodymium, the latter is the only metal that cannot be manufactured industrially by electrolysis of these salts. Indeed, it is mentioned in the article by T. KURITA (Denki Kagaku, 1967, 35 (7) p.496-501) that yields of 6 to 20% of pure neodymium are obtained by electrolysis in a molten bath - neodymium chloride, potassium chloride -.
  • neodymium alloys more particularly neodymium and magnesium alloys, which consists of using neodymium chloride, an alkali metal and magnesium, all the reagents being introduced and kept in the molten state throughout the duration of the reaction.
  • the objective of the present invention is to have new neodymium alloys obtained according to an industrial manufacturing process.
  • One of the objects of the present invention resides in a process for the manufacture of neodymium and iron alloys characterized in that it consists in reducing a neodymium fluoride using calcium, in the presence of iron; the quantity of iron being defined so that the neodymium-iron alloy has an iron content of 5 to 30%.
  • Another object of the present invention are the alloys obtained according to the method of the invention.
  • neodymium fluoride is used.
  • Neodymium fluoride is available in the anhydrous state because it is a low hygroscopic product.
  • the drying time can vary between 2 and 24 hours.
  • drying conditions are not critical and are given on a preferential basis.
  • the particle size of neodymium fluoride can vary. It is commercially available in the form of a powder, the particle size of which varies from 40 to 150 ⁇ m. The size of the particles influencing the reduction speed, it is recommended that the powder is fine which can lead to a grinding operation so that the average diameter of the neodymium fluoride particles is less than 100 ⁇ m. There is no lower diameter limit.
  • the reducing metal used in the process of the invention is calcium.
  • the reducing metal is used in the form in which it is sold, whether it is in the solid state or in the form of pellets or balls.
  • a preferred variant of the process of the invention consists in adding to the reaction medium, calcium chloride in order to lower the melting point and the density of the slag formed in the reaction so that the alloy formed neodymium-iron separates easier.
  • the method of the invention consists in mixing a neodymium fluoride, calcium. iron and calcium chloride in the proportions given below.
  • the amount of calcium can vary within wide limits. However, it is advantageous to use an amount sufficient to reduce the neodymium fluoride but it should not be too large if one does not wish to find it, in an important way, in the final alloy.
  • the amount of reducing metal is at least equal to the stoichiometric amount or even in slight excess, up to 20% of the stoichiometric amount.
  • the amount of iron is adjusted according to the desired composition of the alloy. It is such that a fusible alloy with neodymium is obtained at the reaction temperature. It is calculated so that the iron represents from 5 to 30% of the weight of the alloy obtained.
  • the amount of calcium chloride added is adjusted in order to obtain a slag containing from 30 to 70% by weight of calcium chloride and preferably 60 to 70%.
  • the different neodymium and calcium halides and iron constitute "a filler" having the desired weight composition.
  • the constituents of this charge can be reacted in any order: by simultaneous mixing of all the constituents or by making premixes, on the one hand, the neodymium and calcium halides and on the other hand the calcium and iron.
  • the reaction is carried out at a temperature between 800 ° C and 1100 ° C.
  • the upper temperature limit is not critical and can reach a value as high as 1400 ° C.
  • a temperature between 900 ° C and 1100 ° C is chosen.
  • the reaction is carried out under atmospheric pressure but in an inert gas atmosphere.
  • the air is excluded by lowering ment of the pressure up to a non-critical value, for example between 1 mm and 100 mm of mercury, then a scanning of inert gases is carried out: rare gases, in particular argon.
  • rare gases in particular argon. It is desirable to subject the rare gas to a dehydration and deoxygenation treatment carried out according to the usual techniques, for example by passage through a molecular sieve.
  • the inert atmosphere is maintained throughout the reduction.
  • the duration of the reaction depends on the capacity of the apparatus and its ability to rapidly rise in temperature. Generally once the desired temperature has been reached, it is maintained for a variable duration of approximately 30 minutes to 3 hours.
  • a metallic phase consisting of the neodymium-iron alloy on which floats a slag consisting of CaF2-CaCl2 having a density lower than that of the alloy.
  • the alloy can be immediately separated from the slag by hot casting or allowed to cool under an inert gas atmosphere at room temperature (15 to 25 ° C) so that the alloy solidifies and can then be demolded.
  • the yield of neodymium in the alloy expressed relative to the neodymium contained in the halide varies from 80 to 96%.
  • the method of the invention as described, can be implemented in an apparatus of conventional type, used in metallurgy.
  • the reduction is carried out in a crucible placed in a reactor made of a material resistant to hydrofluoric and hydrochloric vapors. It can be chosen from refractory steel, for example, steel containing 25% chromium and 20% nickel but preferably inconel which is an alloy containing nickel, chromium (20%), iron (5%), molybdenum (8-10%).
  • Said reactor is equipped with a temperature control device (eg thermocouple), an inlet and outlet of inert gases. It is provided in its upper part with a double envelope in which circulates a coolant.
  • a temperature control device eg thermocouple
  • This reactor is placed in an induction furnace or in an furnace heated by electrical resistances.
  • a crucible in which the temperature control device is immersed is placed at the bottom of the reactor. It must be made of a material resistant to neodymium fluoride or have a coating resistant to them. Preferably, a tantalum crucible is used.
  • the molten alloy can be cast in molds, for example, cast iron.
  • the alloys obtained according to the present invention have the following weight composition: - from 70 to 95% of neodymium - 5 to 30% iron - less than 3% of reducing metal
  • compositions of the neodymium-iron alloys used . 83 to 91% neodymium . 9 to 16% iron . less than 1% calcium
  • the alloys obtained according to the present invention are very rich in neodymium since they can contain up to 95%.
  • They can be used as master alloys in particular in the manufacture of permanent magnets.
  • the methods for assaying the various constituents of the alloy will be explained briefly by the following techniques: - the neodymium is dosed, according to the chemical method described below and consists of: . dissolving the alloy sample in an acid medium, . bring the solution obtained to a boil, . precipitating the reducing metal, iron and neodymium in the form of their hydroxide at pH 9, by treatment with ammonia, then filtering and washing the precipitates obtained, . redissolving the precipitate of neodymium hydroxide in an acid medium, . adding ammonium oxalate to the solution obtained in boiling to obtain neodymium oxalate, .
  • neodymium oxalate calcining the neodymium oxalate at 900 ° C for 1 hour to transform it into oxide, . weighing the quantity of oxide obtained, thus making it possible to calculate the quantity of neodymium contained in the alloy.
  • the other metals, reducing metal and iron are titrated by atomic absorption.
  • a premix containing 382.2 g of calcium chloride in the dry state and 281.4 g of neodymium fluoride having an average particle diameter of 60 ⁇ m is then made.
  • the previously defined load is then ready for use.
  • the calciothermic reduction reaction of neodymium fluoride is carried out in a tantalum crucible of about 1 liter placed at the bottom of an inconel reactor which is equipped with an inlet and an argon outlet and a thermocouple introduced into a thermometric sheath which is immersed in the reaction medium contained in the crucible: the upper part of the reactor is provided with a double jacket in which cold water circulates (about 10 ° C).
  • the proportion of the constituents of the charge is defined so that the conditions set out below are met: - that we obtain an alloy containing 12% iron - that there is an excess of calcium of 20% compared to the required stoichiometric weight - that a slag containing 70% calcium chloride is formed.
  • a temperature rise is carried out at the same time until the temperature fixed at 1100 ° C. is obtained; this temperature being kept constant for another 30 minutes.
  • neodymium-iron alloy 562 g are collected and 188 g of a neodymium-iron alloy are recovered by hot casting in a cast iron ingot mold.
  • the neodymium yield in the alloy expressed relative to the neodymium contained in the neodymium fluoride is 81%.
  • the analysis of the alloy obtained is as follows: - 87.4% neodymium - 12% iron - 0.6% calcium.
EP88100014A 1983-07-05 1984-06-22 Verfahren zur Herstellung von Neodymlegierungen Expired - Lifetime EP0272250B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT88100014T ATE81156T1 (de) 1983-07-05 1984-06-22 Verfahren zur herstellung von neodymlegierungen.

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
FR8311139 1983-07-05
FR8311139A FR2548687B1 (fr) 1983-07-05 1983-07-05 Alliages de neodyme et leur procede de fabrication
FR838314392A FR2551769B2 (fr) 1983-07-05 1983-09-09 Alliages de neodyme et leur procede de fabrication
FR8314392 1983-09-09

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
EP84401307.8 Division 1984-06-22

Publications (2)

Publication Number Publication Date
EP0272250A1 true EP0272250A1 (de) 1988-06-22
EP0272250B1 EP0272250B1 (de) 1992-09-30

Family

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Family Applications (2)

Application Number Title Priority Date Filing Date
EP84401307A Expired EP0134162B1 (de) 1983-07-05 1984-06-22 Neodymlegierungen und Verfahren zur Herstellung derselben
EP88100014A Expired - Lifetime EP0272250B1 (de) 1983-07-05 1984-06-22 Verfahren zur Herstellung von Neodymlegierungen

Family Applications Before (1)

Application Number Title Priority Date Filing Date
EP84401307A Expired EP0134162B1 (de) 1983-07-05 1984-06-22 Neodymlegierungen und Verfahren zur Herstellung derselben

Country Status (9)

Country Link
US (1) US4636353A (de)
EP (2) EP0134162B1 (de)
JP (1) JPS6046346A (de)
KR (1) KR920006603B1 (de)
AU (1) AU579579B2 (de)
BR (1) BR8403289A (de)
CA (1) CA1253721A (de)
DE (2) DE3479595D1 (de)
FR (1) FR2551769B2 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0364089A1 (de) * 1988-10-11 1990-04-18 General Motors Corporation Verfahren zum Dekalzifieren von Seltenerdmetallen, erhalten durch ein Reduktions-Diffusionsverfahren

Families Citing this family (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4612047A (en) * 1985-10-28 1986-09-16 The United States Of America As Represented By The United States Department Of Energy Preparations of rare earth-iron alloys by thermite reduction
US4837109A (en) * 1986-07-21 1989-06-06 Hitachi Metals, Ltd. Method of producing neodymium-iron-boron permanent magnet
FR2607520B1 (fr) * 1986-11-27 1992-06-19 Comurhex Procede d'elaboration par metallothermie d'alliages purs a base de terres rares et de metaux de transition
US4992096A (en) * 1989-06-09 1991-02-12 The Dow Chemical Company Metallothermic reduction or rare earth metals
US5073337A (en) * 1990-07-17 1991-12-17 Iowa State University Research Foundation, Inc. Rare earth/iron fluoride and methods for making and using same
US5087291A (en) * 1990-10-01 1992-02-11 Iowa State University Research Foundation, Inc. Rare earth-transition metal scrap treatment method
US5174811A (en) * 1990-10-01 1992-12-29 Iowa State University Research Foundation, Inc. Method for treating rare earth-transition metal scrap
US5240513A (en) * 1990-10-09 1993-08-31 Iowa State University Research Foundation, Inc. Method of making bonded or sintered permanent magnets
US5242508A (en) * 1990-10-09 1993-09-07 Iowa State University Research Foundation, Inc. Method of making permanent magnets
US5129945A (en) * 1990-10-24 1992-07-14 The United States Of America As Represented By The Secretary Of The Interior Scrap treatment method for rare earth transition metal alloys
US5314526A (en) * 1990-12-06 1994-05-24 General Motors Corporation Metallothermic reduction of rare earth fluorides
US5238489A (en) * 1992-06-30 1993-08-24 The United States Of America As Represented By The Secretary Of The Interior Leaching/flotation scrap treatment method
US6755924B2 (en) 2001-12-20 2004-06-29 General Electric Company Method of restoration of mechanical properties of a cast nickel-based super alloy for serviced aircraft components
US8109349B2 (en) 2006-10-26 2012-02-07 Schlumberger Technology Corporation Thick pointed superhard material
US8590644B2 (en) * 2006-08-11 2013-11-26 Schlumberger Technology Corporation Downhole drill bit
US8215420B2 (en) * 2006-08-11 2012-07-10 Schlumberger Technology Corporation Thermally stable pointed diamond with increased impact resistance
US7637574B2 (en) 2006-08-11 2009-12-29 Hall David R Pick assembly
US9145742B2 (en) 2006-08-11 2015-09-29 Schlumberger Technology Corporation Pointed working ends on a drill bit
US8567532B2 (en) 2006-08-11 2013-10-29 Schlumberger Technology Corporation Cutting element attached to downhole fixed bladed bit at a positive rake angle
US8622155B2 (en) * 2006-08-11 2014-01-07 Schlumberger Technology Corporation Pointed diamond working ends on a shear bit
US8714285B2 (en) * 2006-08-11 2014-05-06 Schlumberger Technology Corporation Method for drilling with a fixed bladed bit
US9051795B2 (en) 2006-08-11 2015-06-09 Schlumberger Technology Corporation Downhole drill bit
US9068410B2 (en) 2006-10-26 2015-06-30 Schlumberger Technology Corporation Dense diamond body
US8960337B2 (en) 2006-10-26 2015-02-24 Schlumberger Technology Corporation High impact resistant tool with an apex width between a first and second transitions
US8540037B2 (en) 2008-04-30 2013-09-24 Schlumberger Technology Corporation Layered polycrystalline diamond
CN102089835A (zh) * 2008-07-08 2011-06-08 丹麦理工大学 磁致热致冷器
US20100242375A1 (en) * 2009-03-30 2010-09-30 Hall David R Double Sintered Thermally Stable Polycrystalline Diamond Cutting Elements
BR112014008207B1 (pt) 2011-10-20 2019-09-10 Akzo Nobel Chemicals Int Bv processo para a purificação de uma alimentação líquida
EP2748139B1 (de) 2011-10-20 2017-04-26 Akzo Nobel Chemicals International B.V. Verfahren zur hydrodechlorierung einer flüssigkeitszufuhr mit dichloressigsäure
RU2596563C1 (ru) * 2015-04-23 2016-09-10 Федеральное государственное унитарное предприятие "Всероссийский научно-исследовательский институт авиационных материалов" (ФГУП "ВИАМ") Способ получения магнитотвердого материала
CN114891953B (zh) * 2022-03-31 2024-03-08 包头市英思特稀磁新材料股份有限公司 一种提高烧结钕铁硼出材率的方法

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR489155A (fr) * 1917-04-19 1918-12-28 Maurice Duburguet Préparation des métaux des terres rares
US1648954A (en) * 1921-09-29 1927-11-15 Westinghouse Lamp Co Production of rare metals and alloys thereof
FR986924A (fr) * 1943-12-11 1951-08-07 Procédé de préparation de métaux des terres rares
US3186834A (en) * 1961-03-02 1965-06-01 Dow Chemical Co Preparation of rare earth metal sponge
US3295963A (en) * 1962-07-27 1967-01-03 Pechiney Prod Chimiques Sa Alloys containing rare earth metals
AT329884B (de) * 1973-07-19 1976-06-10 Treibacher Chemische Werke Ag Verfahren zur herstellung von lanthan-, cer-,praseodym- und neodym-metall und -legierungen derselben sowie von mischmetallen

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5696834A (en) * 1979-12-28 1981-08-05 Mitsubishi Monsanto Chem Co Compound semiconductor epitaxial wafer and manufacture thereof
US4496395A (en) * 1981-06-16 1985-01-29 General Motors Corporation High coercivity rare earth-iron magnets
JPS5976A (ja) * 1982-06-22 1984-01-05 日本電気株式会社 放射線治療用高エネルギｃｔ
EP0108474B2 (de) * 1982-09-03 1995-06-21 General Motors Corporation RE-TM-B Legierungen, deren Herstellung und permanent Magnete die solche Legierungen enthalten
JPS6263642A (ja) * 1986-09-12 1987-03-20 Sumitomo Special Metals Co Ltd 磁石素材用希土類合金及びその製造方法

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR489155A (fr) * 1917-04-19 1918-12-28 Maurice Duburguet Préparation des métaux des terres rares
US1648954A (en) * 1921-09-29 1927-11-15 Westinghouse Lamp Co Production of rare metals and alloys thereof
FR986924A (fr) * 1943-12-11 1951-08-07 Procédé de préparation de métaux des terres rares
US3186834A (en) * 1961-03-02 1965-06-01 Dow Chemical Co Preparation of rare earth metal sponge
US3295963A (en) * 1962-07-27 1967-01-03 Pechiney Prod Chimiques Sa Alloys containing rare earth metals
AT329884B (de) * 1973-07-19 1976-06-10 Treibacher Chemische Werke Ag Verfahren zur herstellung von lanthan-, cer-,praseodym- und neodym-metall und -legierungen derselben sowie von mischmetallen

Non-Patent Citations (6)

* Cited by examiner, † Cited by third party
Title
CHEMICAL ABSTRACTS, vol. 93, 1980, page 379, résumé no. 226435c, Columbus, Ohio, US; V.D. SAVIN et al.: "Kinetics of the reduction of cerium and neodymium from chlorides by calcium", & ZH. FIZ. KHIM. 1980, 54(9), 2241-5 *
CHEMICAL ABSTRACTS, vol. 94, 1981, page 213, résumé no. 195573k, Columbus, Ohio, US; G.N. ZVIADADZE et al.: "Kinetics of aluminothermal reduction of neodymium from fluoride", & IZV. AKAD. NAUK SSSR, Met. 1981 (1), 14-17 *
CHEMICAL ABSTRACTS, vol. 95, 1981, page 463, résumé no. 157685m, Columbus, Ohio, US; G.N. ZVIADADZE et al.: "Thermodynamics of the aluminothermal reduction of scandium, yttrium, and neodymium from fluorides", & DEPOSITED DOC. 1980, VINITI, 1804-80, 19pp. *
CHIMIE ET INDUSTRIE, vol. 77, no. 2, février 1957, pages 277-288, Société de productions documentaires, Rueil-Malmaison, FR; F. TROMBE: "Préparation et propriétés des métaux des terres rares" *
GMELIN HANDBUCH DER ANORGANISCHEN CHEMIE, partie B2, système no. 39, pages 214-215, Springer Verlag, Berlin, DE *
M. BOUISSIERES et al.: "Nouveau traité de chimie minérale", tome VII, 1959, pages 488-525, Masson Editeurs *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0364089A1 (de) * 1988-10-11 1990-04-18 General Motors Corporation Verfahren zum Dekalzifieren von Seltenerdmetallen, erhalten durch ein Reduktions-Diffusionsverfahren

Also Published As

Publication number Publication date
KR850001297A (ko) 1985-03-18
JPS6046346A (ja) 1985-03-13
DE3485950D1 (de) 1992-11-05
DE3485950T2 (de) 1993-02-25
BR8403289A (pt) 1985-06-18
FR2551769B2 (fr) 1990-02-02
KR920006603B1 (ko) 1992-08-10
AU579579B2 (en) 1988-12-01
DE3479595D1 (en) 1989-10-05
JPH0224902B2 (de) 1990-05-31
EP0134162A1 (de) 1985-03-13
EP0272250B1 (de) 1992-09-30
AU3008184A (en) 1985-01-10
CA1253721A (fr) 1989-05-09
US4636353A (en) 1987-01-13
EP0134162B1 (de) 1989-08-30
FR2551769A2 (fr) 1985-03-15

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