1192:
commission cited hidden complications if more than one magnet becomes attached across tissue inside the body. Another recall was issued for
Buckyballs in 2012 along with similar products marketed as toys in the US. Recalls and administrative complaints were filed against other similar US companies. Maxfield & Oberton refused the recall and continued selling their desktop toys. The company launched a political campaign against the CPSC, and Craig Zucker, the company's co-founder, debated the safety commission on FOX News.
33:
93:
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exposure to danger whatsoever." As of
January 2017, many brands of magnet spheres including Zen Magnets have resumed the sale of small neodymium magnet spheres following a successful appeal by Zen Magnets in the Tenth Circuit US Court of Appeals which vacated the 2012 CPSC regulation banning these products and thereby rendered the sale of small neodymium magnets once again legal in the United States. It was the CPSC's first such loss in more than 30 years.
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1227:. On October 26, 2017, the CPSC filed an administrative complaint against Zen Magnets, alleging that the magnet sets contained product defects that created a substantial risk of injury to children, declaring that "It is illegal under federal law for any person to sell, offer for sale, manufacture, distribute in commerce, or import into the United States any Zen Magnets and Neoballs."
1130:
1261:'s ETN-Demeter project (European Training Network for the Design and Recycling of Rare-Earth Permanent Magnet Motors and Generators in Hybrid and Full Electric Vehicles) is examining sustainable design of electric motors used in vehicles. They are, for example, designing electric motors in which the magnets can be easily removed for recycling the rare earth metals.
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to get too near each other can strike each other with enough force to chip and shatter the brittle material, and the flying chips can cause injuries. Starting in 2005, powerful magnets breaking off toys or from magnetic construction sets started causing injuries and deaths. Young children who have swallowed several magnets have had a fold of the
1122:
456:), the temperature at which the material loses its magnetism. Rare-earth magnets have higher remanence, much higher coercivity and energy product, but (for neodymium) lower Curie temperature than other types. The table below compares the magnetic performance of the two types of rare-earth magnets, neodymium (Nd
1219:
A study published in the
Journal of Pediatric Gastroenterology and Nutrition found a significant increase in magnet ingestions by children after 2017, including "a 5-fold increase in the escalation of care for multiple magnet ingestions". On June 3, 2020, the CPSC submitted a "Petition Response Staff
1145:
The greater force exerted by rare-earth magnets creates hazards that are not seen with other types of magnet. Magnets larger than a few centimeters are strong enough to cause injuries to body parts pinched between two magnets or a magnet and a metal surface, even causing broken bones. Magnets allowed
1215:
In March 2016, Zen
Magnets (a manufacturer of neodymium magnet spheres) won in a major 2014 court hearing concerning the danger posed by "defective" warning labels on their spherical magnets. It was decided by a DC court (CPSC Docket No: 12-2) that "Proper use of Zen Magnets and Neoballs creates no
1171:
passed a rule in 2012 restricting rare-earth magnet size in consumer products, but it was vacated by a US federal court decision in
November 2016, in a case brought by the one remaining manufacturer. After the rule was nullified, the number of ingestion incidents in the country rose sharply, and is
1166:
A voluntary standard for toys, permanently fusing strong magnets to prevent swallowing, and capping unconnected magnet strength, was adopted in 2007. In 2009, a sudden growth in sales of magnetic desk toys for adults caused a surge in injuries, with emergency room visits estimated at 3,617 in 2012.
1180:
issued a recall on packaging labeled 13+. According to the CPSC, 175,000 units had been sold to the public. Fewer than 50 were returned. Buckyballs labeled "Keep Away From All
Children" were not recalled. Subsequently, Maxfield & Oberton changed all mentions of "toy" to "desk toy", positioning
1191:
Further investigation by the CPSC published in 2012 found an increasing trend of magnet ingestion incidents in young children and teens since 2009. Incidents involving older children and teens were unintentional and the result of using the magnets to mimic body piercings such as tongue studs. The
845:
Originally, the high cost of these magnets limited their use to applications requiring compactness together with high field strength. Both the raw materials and the patent licenses were expensive. However, since the 1990s, NIB magnets have become steadily less expensive, and their lower cost has
1157:
The swallowing of small magnets such as neodymium magnetic spheres can result in intestinal injury requiring surgery. The magnets attract each other through the walls of the stomach and intestine, perforating the bowel. The U.S. Centers for
Disease Control reported 33 cases as of 2010 requiring
1211:
filed administrative complaints, attempting to ban the sale of
Buckyballs and Zen Magnets. Zen Magnets LLC is the first company to ever receive this sort of complaint without record of injury. In November 2012, Buckyballs announced that they had stopped production due to a CPSC lawsuit.
2415:
1767:
1918:
943:
Capture of fine metallic particles in lubricating oils (crankcases of internal combustion engines, also gearboxes and differentials), so as to keep said particles out of circulation, thereby rendering them unable to cause abrasive wear of moving machine
1893:
The U.S. Consumer
Product Safety Commission (CPSC) is aware of at least 33 cases of children being injured from ingesting magnets. A 20-month-old died, and at least 19 other children from 10 months to 11 years old required surgery to remove ingested
345:
grains, which are aligned in a powerful magnetic field during manufacture, so their magnetic axes all point in the same direction. The resistance of the crystal lattice to turning its direction of magnetization gives these compounds a very high
2405:
1757:
1175:
In 2009 US company
Maxfield & Oberton, maker of Buckyballs, decided to repackage sphere magnets and sell them as toys. Buckyballs launched at New York International Gift Fair in 2009 and sold in the hundreds of thousands before the
373:; in other elements, almost all of the electrons exist in pairs with opposite spins, so their magnetic fields cancel out, but in rare-earths, there is much less magnetic cancellation. This is a consequence of incomplete filling of the
2457:
1925:
2090:
2478:
Mr Roberts said magnets from novelty products and executive toys had been swallowed by young children, while some older children and teenagers had swallowed magnets after using them as imitation tongue or lip
377:, which can contain up to 7 unpaired electrons. In a magnet, it is the unpaired electrons, aligned so they spin in the same direction, which generate the magnetic field. This gives the materials high
1296:(ARPA-E) has sponsored a Rare Earth Alternatives in Critical Technologies (REACT) program, to develop alternative materials. In 2011, ARPA-E awarded $ 31.6 million to fund Rare-Earth Substitute projects.
2429:
310:(the temperature above which their ferromagnetism disappears) are below room temperature, so in pure form their magnetism only appears at low temperatures. However, they form compounds with the
2025:
735:), the first family of rare-earth magnets invented, are less used than neodymium magnets because of their higher cost and lower magnetic field strength. However, samarium–cobalt has a higher
1024:, for which rare-earth magnets have gained popularity in the miniatures gaming community for their small size and relative strength assisting in basing and swapping weapons between models.
2465:
1969:
412:
of neodymium magnets is about 18 times greater than "ordinary" magnets by volume. This allows rare-earth magnets to be smaller than other magnets with the same field strength.
2350:
Reeves, Patrick T.; Rudolph, Bryan; Nylund, Cade M. (2020). "Magnet Ingestions in Children Presenting to Emergency Departments in the United States 2009–2019: A Problem in Flux".
119:. Developed in the 1970s and 1980s, rare-earth magnets are the strongest type of permanent magnets made, producing significantly stronger magnetic fields than other types such as
2582:
1805:
1220:
Briefing Package" to the commission, even after the petition was rescinded. It outlines a desire to conduct research in 2021 with a suggested rule proposal in 2022 for a vote.
870:
magnets in the many applications in modern technology requiring powerful magnets. Their greater strength allows smaller and lighter magnets to be used for a given application.
1184:
In the United States, as a result of an estimated 2,900 emergency room visits between 2009 and 2013 due to either "ball-shaped" or "high-powered" magnets, or both, the
2393:
2098:
1208:
200:. Some countries classify rare earth metals as strategically important, and Chinese export restrictions on these materials have led other countries, including the
743:. They are highly resistant to oxidation, but sintered samarium–cobalt magnets are brittle and prone to chipping and cracking and may fracture when subjected to
192:
in the Earth's crust as tin or lead, but rare earth ores do not exist in seams (like coal or copper), so in any given cubic kilometre of crust they are "rare".
788:
B), sometimes abbreviated as NIB. Neodymium magnets are used in numerous applications requiring strong, compact permanent magnets, such as electric motors for
1642:"Magnetic hyperthermia cancer therapy using rare earth metal-based nanoparticles: An investigation of Lanthanum strontium Manganite's hyperthermic properties"
2558:
Furlani Edward P. (2001). "Permanent Magnet and Electromechanical Devices: Materials, Analysis and Applications". Academic Press Series in Electromagnetism.
1372:
2164:
2057:
2032:
1276:
for the project "Rare Earth Element reCYCling with Low harmful Emissions : REE-CYCLE", which aimed at finding new processes for the recycling of
189:
1293:
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surgery and one death. The magnets have been swallowed by both toddlers and teens (who were using the magnets to pretend to have tongue piercings).
1873:
1200:
1185:
1177:
1168:
216:
Neodymium magnets (small cylinders) lifting steel balls. As shown here, rare-earth magnets can easily lift thousands of times their own weight.
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1843:
1423:
1355:
1817:
2077:
1490:
772:
magnets, invented in the 1980s, are the strongest and most affordable type of rare-earth magnet. They are made of an alloy of neodymium,
1292:
has identified a need to find substitutes for rare-earth metals in permanent-magnet technology and has begun funding such research. The
2629:
1950:
1530:
1289:
247:
326:, and some of these compounds have Curie temperatures well above room temperature. Rare-earth magnets are made from these compounds.
2563:
2394:
https://www.cpsc.gov/s3fs-public/Informational%20Briefing%20Package%20Regarding%20Magnet%20Sets.pdf?FKVcZpHmPKWCZNb7JEl6Ir0a31WV72PI
2138:
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54:
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1077:
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Beichner and Serway. Physics for Scientists & Engineers with Modern Physics. 5th ed. Orlando: Saunders College, 2000: 963
1272:
also awarded to Principal Investigator, Prof. Thomas Zemb, and co-Principal Investigator, Dr. Jean-Christophe P. Gabriel, an
1114:
251:
1615:
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1866:
1039:
are attached to therapeutics and guided by an external magnetic field to concentrate and retain them at the desired site.
2689:
366:
1831:
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the product as a stress-reliever for adults and restricted sales from stores that sold primarily children's products.
937:, employing rare earth magnets for generating electricity in a shaking motion or rotating (hand-crank-powered) motion
719:
143:
1172:
estimated to exceed 1,500 in 2019, leading the CPSC to advise children under the age of 14 to not use the magnets.
1384:
1035:
generate localized heat within tumor cells, leading to their selective destruction. In targeted delivery systems,
405:, so these materials have the potential for storing large amounts of magnetic energy. The magnetic energy product
2694:
2168:
1725:
1595:
Curie Temperature." McGraw-Hill Encyclopedia of Science & Technology. 8th ed. 20 vols. N.P: McGraw-Hill, 1997
1269:
1249:
announced a ban on the import and sale of neodymium magnet sets in New Zealand, effective from January 24, 2013.
1021:
1970:
Buckyballs® High Powered Magnets Sets Recalled by Maxfield and Oberton Due to Violation of Federal Toy Standard
341:
but is very difficult to magnetize in other directions. Like other magnets, rare-earth magnets are composed of
236:
47:
41:
2583:"The Dependence of Magnetic Properties and Hot Workability of Rare Earth-Iron-Boride Magnets Upon Composition"
1273:
796:, magnetic hold-downs, and jewellery clasps. They have the highest magnetic field strength and have a higher
2569:
Campbell Peter (1996). "Permanent Magnet Materials and their Application" (Cambridge Studies in Magnetism).
2243:
990:
986:
981:
255:
240:
2392:
30. ^Staff Briefing Package In Response to Petition CP 17-1, Requesting Rulemaking Regarding Magnet Sets.
1986:
1007:
battery and a small rare earth magnet, used as a form of non-destructive graffiti and temporary public art.
2443:
1147:
1036:
1032:
1028:
968:
58:
2505:
839:
740:
1604:
Hall, H.E and J.R. Hook. Solid State Physics. 2nd ed. Chichester: John Wiley & Sons Ltd, 1991: 226.
92:
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899:
212:
2410:
1991:
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382:
351:
347:
334:
182:
165:
The development of rare-earth magnets began around 1966, when K. J. Strnat and G. Hoffer of the US
2621:
2375:
2094:
1955:
1277:
1196:
739:, creating a niche for these magnets in applications where high field strength is needed at high
204:, to initiate research programs to develop strong magnets that do not require rare earth metals.
116:
761:
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2367:
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1444:
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1345:
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Sales of "certain products with small, powerful magnets" are prohibited in Canada since 2015.
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off a surface layer or to crumble into a powder. Use of protective surface treatments such as
801:
736:
446:
370:
307:
303:
1577:
Introduction to Magnets and Magnetic Materials, David Jiles, Ames Laboratrories, US DoE, 1991
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Industrial uses such as maintaining product purity, equipment protection, and quality control
2605:
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1653:
1411:
1305:
929:
867:
756:
662:
342:
311:
139:
120:
108:
2406:"Number of children swallowing dangerous magnets surges as industry largely polices itself"
1758:"Number of children swallowing dangerous magnets surges as industry largely polices itself"
1522:
965:
animation: as tie-downs when the use of traditional screw and nut tie-downs is impractical.
2461:
2142:
2116:
1242:, a permanent ban on the sale of neodymium magnets went into effect throughout Australia.
1239:
975:
878:
862:
Since their prices became competitive in the 1990s, neodymium magnets have been replacing
793:
362:
2601:
2305:
2218:
1109:
2537:
2276:
1701:
1674:
1317:
1265:
1258:
1204:
925:
914:
838:-resin coating can provide corrosion protection; the majority of neodymium magnets use
337:. This means that a crystal of the material preferentially magnetizes along a specific
128:
1556:
854:
2673:
2379:
1982:
1246:
1150:
pinched between the magnets, causing injury and in one case intestinal perforations,
1016:
744:
502:
355:
299:
291:
201:
2625:
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1137:
1004:
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952:
907:
883:
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488:
338:
132:
1516:
17:
2363:
2012:
1781:
1658:
1641:
1415:
196:
has the highest production but China imports significant amounts of REE ore from
135:, whereas ferrite or ceramic magnets typically exhibit fields of 0.5 to 1 tesla.
962:
920:
889:
225:
1877:
1836:
Business & Professional Ethics for Directors, Executives & Accountants
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1311:
1129:
893:
797:
428:
287:
96:
2617:
2609:
2091:"Gillibrand Urges Feds to Ban the Sale of Dangerous High-Powered Toy Magnets"
1223:
As of 2019, manufacturers are working on a similar voluntary standard at the
2656:
2331:"How One Man's Quest to Save His Magnets Became a Massive Regulatory Battle"
1867:"CPSC Safety Alert – Ingested Magnets Can Cause Serious Intestinal Injuries"
1323:
811:
805:
769:
417:
378:
151:
2371:
1710:
188:
The term "rare earth" can be misleading, as some of these metals can be as
2335:
1818:
Young kids can swallow magnets, seriously damage intestines, doctors warn
1010:
815:
724:
329:
The greater strength of rare-earth magnets is mostly due to two factors:
2165:"Federal agency targets Denver magnet company with no history of injury"
2661:
530:
438:), the material's resistance to becoming demagnetized; energy product (
374:
197:
170:
159:
155:
147:
1491:"Raring to Fight: The U.S. Tangles with China over Rare-Earth Exports"
1151:
956:
863:
823:
728:
640:
323:
319:
174:
124:
1188:(CPSC) has undergone rulemaking to attempt to restrict their sale.
1121:
162:
to protect them from breaking, chipping, or crumbling into powder.
2519:
1136:
1128:
1120:
1108:
853:
835:
777:
760:
211:
193:
112:
91:
1675:"Magnetic nanoparticles as targeted delivery systems in oncology"
416:
Some important properties used to compare permanent magnets are:
2058:"CPSC Warns High-Powered Magnets and Children Make a Deadly Mix"
1224:
1113:
Two objects made of neodymium magnets. The right object has the
827:
819:
773:
684:
315:
295:
89:
Strong permanent magnet made from alloys of rare-earth elements
2196:
1047:
1000:
831:
800:(which makes them magnetically stable), but they have a lower
219:
26:
1320: – Searching in outdoor waters for ferromagnetic objects
2299:"10th Circuit Court of Appeals Opinion, Zen Magnets v. CPSC"
2212:"10th Circuit Court of Appeals Opinion, Zen Magnets v. CPSC"
2492:"VIC: Update: Permanent ban on small, high powered magnets"
2113:"CPSC Sues Maxfield & Oberton Over Hazardous Buckyball"
1125:
Neodymium magnet spheres constructed in the shape of a cube
1308: – Production model to minimise wastage and emissions
971:
experimentation, the study of magnetic field dynamics and
354:
within the finished magnet does not reduce the material's
1987:"Craig Zucker: What Happens When a Man Takes on the Feds"
1838:(Fifth ed.). South-Western College Pub. p. 33.
1906:
Feds file suit against Buckyballs, retailers ban product
1553:"Research Funding for Rare Earth Free Permanent Magnets"
1466:
The lanthanides and their interrelations with biosystems
131:
typically produced by rare-earth magnets can exceed 1.2
1806:
Child has bowel surgery after swallowing magnetic balls
1072:
1031:
made from rare earth metals. In magnetic hyperthermia,
350:(resistance to being demagnetized), so that the strong
2648:
Standard Specifications for Permanent Magnet Materials
2581:
Brown, D. N.; B. Smith; B. M. Ma; P. Campbell (2004).
1951:"For Buckyballs Toys, Child Safety Is a Growing Issue"
1616:"Everything You Need to Know About Rare Earth Magnets"
1133:
Neodymium magnet spheres used to form different shapes
846:
inspired new uses such as magnetic construction toys.
427:), which measures the strength of the magnetic field;
2657:"Iron-nitrogen compound forms strongest magnet known"
2352:
Journal of Pediatric Gastroenterology & Nutrition
1141:"Bucky Ball" toy neodymium magnet spheres in close-up
1027:
Research on cancer treatment is exploring the use of
361:
Secondly, atoms of rare-earth elements can have high
333:
Firstly, their crystalline structures have very high
2458:"Interim ban on novelty products with small magnets"
1373:"More Mileage Than Programmed From Military R&D"
1326: – Converting waste materials into new products
1972:, Consumer Product Safety Commission, May 27, 2010.
873:Common applications of rare-earth magnets include:
765:
Neodymium magnet with nickel plating mostly removed
1924:. Alston & Bird. December 2016. Archived from
1406:Bobber, R. J. (1981). "New Types of Transducers".
948:Other applications of rare-earth magnets include:
1830:Brooks, Leonard J; Dunn, Paul (March 31, 2009).
1209:United States Consumer Product Safety Commission
928:and integrated starter-generators in hybrid and
2464:– Fair Trading. August 23, 2012. Archived from
1726:"How to remove a finger with two super magnets"
2494:. Product Safety Australia. November 15, 2012.
1314: – Trivalent metallic rare-earth elements
1238:In November 2012, following an interim ban in
1195:In June 2012, due to a letter by U.S. Senator
2506:"Ban on the sale of high powered magnet sets"
1081:that contextualizes different points of view.
1067:to certain ideas, incidents, or controversies
989:technology found on roller coaster and other
99:on glass, with a rare-earth magnet underneath
8:
2269:"3/29/16 Update: Whoa. We won | Zen Magnets"
2026:"Safety Standard for Magnet Sets-Final Rule"
2508:. New Zealand Government, January 23, 2013.
2244:"Recall Lawsuits: Adjudicative Proceedings"
1245:In January 2013, Consumer Affairs Minister
254:. Unsourced material may be challenged and
2651:(Magnetic Materials Producers Association)
1408:Underwater Acoustics and Signal Processing
468:), with other types of permanent magnets.
1787:. U.S. Consumer Product Safety Commission
1700:
1690:
1657:
1097:Learn how and when to remove this message
274:Learn how and when to remove this message
77:Learn how and when to remove this message
1547:
1545:
1441:Permanent Magnets in Theory and Practice
1383:(3). US Air Force: 14–23. Archived from
1294:Advanced Research Projects Agency-Energy
470:
40:This article includes a list of general
2248:U.S. Consumer Product Safety Commission
1874:U.S. Consumer Product Safety Commission
1336:
1201:U.S. Consumer Product Safety Commission
1186:U.S. Consumer Product Safety Commission
1178:U.S. Consumer Product Safety Commission
1169:U.S. Consumer Product Safety Commission
445:), the density of magnetic energy; and
2080:, The Washington Post, August 2, 2012.
1371:Lovelace, Alan M. (March–April 1971).
1344:Cullity, B. D.; Graham, C. D. (2008).
2430:"CPSC Issues Decision on Zen Magnets"
2190:Bellini, Jarrett (November 2, 2012).
1808:, Hamilton Spectator, March 13, 2013.
1752:
1750:
1748:
1746:
185:constant of any material then known.
7:
1820:Global News Toronto, March 12, 2013.
1673:Prijic, Sara; Sersa, Gregor (2011).
1464:Sigel, Astrid; Helmut Sigel (2003).
252:adding citations to reliable sources
1640:Tewari, Amit; Sharma, Ritu (2023).
146:. Rare-earth magnets are extremely
1949:Martin, Andrew (August 16, 2012).
1347:Introduction to Magnetic Materials
1290:United States Department of Energy
46:it lacks sufficient corresponding
25:
814:can cause unprotected magnets to
2418:from the original on 2023-06-11.
1770:from the original on 2023-06-11.
1052:
935:Mechanically powered flashlights
842:to provide a robust protection.
224:
31:
2097:. June 19, 2012. Archived from
1489:Walsh, Bryan (March 13, 2012).
731:magnets (chemical formula: SmCo
290:) elements are metals that are
2655:Edwards, Lin (22 March 2010).
2590:IEEE Transactions on Magnetics
1724:Swain, Frank (March 6, 2009).
1614:Marchio, Cathy (Apr 9, 2024).
1115:close-packing of equal spheres
808:than samarium–cobalt magnets.
391:). The maximal energy density
167:Air Force Materials Laboratory
1:
1521:. Diane Publishing. pp.
1468:. US: CRC Press. pp. v.
2364:10.1097/MPG.0000000000002955
2013:Buckyballs Safety Compliance
1659:10.1016/j.rineng.2023.101537
1416:10.1007/978-94-009-8447-9_20
1029:magnetic nanoparticles(MNPs)
464:B) and samarium–cobalt (SmCo
169:discovered that an alloy of
1908:, USA Today, July 26, 2012.
1518:Critical Materials Strategy
1350:. Wiley-IEEE. p. 489.
913:Permanent magnet motors in
804:and are more vulnerable to
367:orbital electron structures
2711:
1443:. US: Wiley. p. 123.
754:
717:
1692:10.2478/v10019-011-0001-z
1537:China rare earth magnets.
1270:European Research Council
181:, had by far the largest
2610:10.1109/TMAG.2004.832240
1832:"Magnetic Toys Can Hurt"
1555:. ARPA-E. Archived from
1439:McCaig, Malcolm (1977).
383:saturation magnetization
2680:Ferromagnetic materials
2139:"CPSC Sues Zen Magnets"
2015:, Maxfield and Oberton.
1274:Advanced Research Grant
1044:Hazards and legislation
987:Launched roller coaster
982:Electrodynamic bearings
150:and also vulnerable to
144:samarium–cobalt magnets
61:more precise citations.
2685:Loudspeaker technology
1919:"CPSC Recall Snapshot"
1732:. Seed Media Group LLC
1646:Results in Engineering
1142:
1134:
1126:
1118:
969:Diamagnetic levitation
859:
858:Neodymium magnet balls
766:
741:operating temperatures
720:Samarium–cobalt magnet
217:
154:, so they are usually
100:
2192:"Bye bye, Buckyballs"
2101:on December 12, 2012.
2078:Buckyballs fight back
1782:"Magnet Safety Alert"
1377:Air University Review
1140:
1132:
1124:
1112:
1075:by rewriting it in a
857:
764:
215:
138:There are two types:
95:
2468:on February 19, 2013
2446:. November 15, 2010.
2311:on December 12, 2016
2224:on December 12, 2016
1730:The Sciencepunk Blog
1515:Chu, Steven (2011).
1410:. pp. 243–261.
1387:on February 24, 2013
1253:Environmental impact
919:High-performance AC
294:, meaning that like
248:improve this section
2690:Magnetic levitation
2602:2004ITM....40.2895B
2538:"REE-CYCLE project"
2411:The Washington Post
2171:on October 24, 2012
2145:on October 28, 2012
1992:Wall Street Journal
1763:The Washington Post
398:is proportional to
352:demagnetizing field
348:magnetic coercivity
335:magnetic anisotropy
183:magnetic anisotropy
117:rare-earth elements
2339:. August 21, 2017.
2095:Kirsten Gillibrand
1956:The New York Times
1559:on 10 October 2013
1197:Kirsten Gillibrand
1143:
1135:
1127:
1119:
860:
767:
371:unpaired electrons
308:Curie temperatures
218:
101:
18:Rare-earth magnets
2575:978-0-521-56688-9
2520:"DEMETER project"
2119:on August 5, 2012
1845:978-0-324-59455-3
1425:978-94-009-8449-3
1357:978-0-471-47741-9
1167:In response, the
1107:
1106:
1099:
1061:This section may
1022:Miniature figures
930:electric vehicles
802:Curie temperature
737:Curie temperature
706:
705:
447:Curie temperature
312:transition metals
304:permanent magnets
284:
283:
276:
140:neodymium magnets
105:rare-earth magnet
87:
86:
79:
16:(Redirected from
2702:
2695:Types of magnets
2666:
2636:
2634:
2628:. Archived from
2596:(4): 2895–2897.
2587:
2546:
2545:
2542:cordis.europa.eu
2534:
2528:
2527:
2516:
2510:
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2460:. Government of
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2396:
2390:
2384:
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2320:
2318:
2316:
2310:
2304:. Archived from
2303:
2295:
2289:
2288:
2286:
2284:
2275:. Archived from
2265:
2259:
2258:
2256:
2254:
2240:
2234:
2233:
2231:
2229:
2223:
2217:. Archived from
2216:
2208:
2202:
2201:
2187:
2181:
2180:
2178:
2176:
2167:. Archived from
2161:
2155:
2154:
2152:
2150:
2141:. Archived from
2135:
2129:
2128:
2126:
2124:
2115:. Archived from
2109:
2103:
2102:
2087:
2081:
2075:
2069:
2068:
2066:
2064:
2054:
2048:
2047:
2045:
2043:
2037:
2031:. Archived from
2030:
2022:
2016:
2010:
2004:
2003:
2001:
1999:
1985:(Aug 30, 2013).
1979:
1973:
1967:
1961:
1960:
1946:
1940:
1939:
1937:
1936:
1930:
1923:
1915:
1909:
1903:
1897:
1896:
1890:
1888:
1883:on March 3, 2012
1882:
1876:. Archived from
1871:
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1620:Stanford Magnets
1611:
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1403:
1397:
1396:
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1392:
1368:
1362:
1361:
1341:
1306:Circular economy
1102:
1095:
1091:
1088:
1082:
1078:balanced fashion
1056:
1055:
1048:
879:hard disk drives
794:hard disk drives
757:Neodymium magnet
687:(Fe) bar magnet
471:
363:magnetic moments
343:microcrystalline
286:The rare-earth (
279:
272:
268:
265:
259:
228:
220:
109:permanent magnet
82:
75:
71:
68:
62:
57:this article by
48:inline citations
35:
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27:
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2553:Further reading
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2518:
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2444:"Magnet safety"
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2279:on June 6, 2016
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1240:New South Wales
1236:
1164:
1148:digestive tract
1103:
1092:
1086:
1083:
1073:help improve it
1070:
1057:
1053:
1046:
926:Traction motors
852:
787:
783:
759:
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722:
716:
714:Samarium–cobalt
711:
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617:Sm(Co,Fe,Cu,Zr)
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2642:
2641:External links
2639:
2638:
2637:
2635:on 2012-04-25.
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2529:
2524:etn-demeter.eu
2511:
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2421:
2414:. 2019-12-26.
2397:
2385:
2358:(6): 699–703.
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2017:
2005:
1983:Ahmari, Sohrab
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1766:. 2019-12-26.
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1318:Magnet fishing
1315:
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1266:European Union
1259:European Union
1254:
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1205:Inez Tenenbaum
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973:superconductor
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911:
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840:nickel plating
790:cordless tools
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755:Main article:
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233:This section
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202:United States
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2647:
2630:the original
2593:
2589:
2541:
2532:
2523:
2514:
2500:
2486:
2477:
2470:. Retrieved
2466:the original
2452:
2438:
2424:
2409:
2400:
2388:
2355:
2351:
2345:
2334:
2325:
2313:. Retrieved
2306:the original
2293:
2281:. Retrieved
2277:the original
2272:
2263:
2251:. Retrieved
2247:
2238:
2226:. Retrieved
2219:the original
2206:
2195:
2185:
2173:. Retrieved
2169:the original
2159:
2149:February 18,
2147:. Retrieved
2143:the original
2133:
2123:February 18,
2121:. Retrieved
2117:the original
2107:
2099:the original
2085:
2073:
2061:. Retrieved
2052:
2040:. Retrieved
2033:the original
2020:
2008:
1998:September 1,
1996:. Retrieved
1990:
1977:
1965:
1954:
1944:
1933:. Retrieved
1926:the original
1913:
1901:
1892:
1885:. Retrieved
1878:the original
1861:
1849:. Retrieved
1835:
1825:
1813:
1801:
1789:. Retrieved
1776:
1761:
1734:. Retrieved
1729:
1719:
1682:
1679:Radiol Oncol
1678:
1668:
1649:
1645:
1635:
1623:. Retrieved
1619:
1609:
1600:
1591:
1582:
1573:
1561:. Retrieved
1557:the original
1536:
1517:
1510:
1500:November 13,
1498:. Retrieved
1494:
1484:
1465:
1459:
1440:
1434:
1407:
1401:
1389:. Retrieved
1385:the original
1380:
1376:
1366:
1346:
1339:
1287:
1284:Alternatives
1263:
1256:
1244:
1237:
1229:
1222:
1218:
1214:
1194:
1190:
1183:
1174:
1165:
1156:
1144:
1093:
1084:
1076:
1065:undue weight
1062:
997:LED Throwies
991:thrill rides
947:
921:servo motors
908:Fishing reel
904:MRI scanners
884:Wind turbine
872:
861:
850:Applications
844:
834:plating and
810:
768:
723:
522:
508:
494:
480:
477:Preparation
450:
439:
432:
421:
415:
406:
399:
392:
385:
339:crystal axis
328:
306:, but their
298:they can be
285:
270:
261:
246:Please help
234:
187:
164:
137:
107:is a strong
104:
102:
73:
64:
45:
2315:January 10,
2228:January 10,
2175:October 31,
1685:(1): 1–16.
1203:Chairwoman
1005:button cell
963:Stop motion
59:introducing
2674:Categories
2479:piercings.
2472:January 6,
1935:2016-12-29
1736:2017-11-01
1331:References
1312:Lanthanide
1278:rare earth
976:levitation
894:headphones
886:generators
798:coercivity
663:Sr-ferrite
429:coercivity
302:to become
300:magnetized
288:lanthanide
264:March 2020
208:Properties
111:made from
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42:references
2618:0018-9464
2380:221885548
1324:Recycling
1087:July 2023
1015:Electric
1011:Desk toys
955:(used in
877:Computer
812:Corrosion
806:oxidation
770:Neodymium
751:Neodymium
690:annealed
667:sintered
645:sintered
629:450–1300
626:0.9–1.15
623:sintered
606:600–2000
600:sintered
583:600–1200
555:750–2000
549:sintered
474:Material
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379:remanence
235:does not
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2626:42516743
2416:Archived
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2283:June 16,
2253:June 16,
2063:July 15,
1894:magnets.
1887:July 23,
1851:July 23,
1768:Archived
1711:22933928
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898:Bicycle
890:speakers
725:Samarium
673:100–300
670:0.2–0.4
657:700–860
648:0.6–1.4
632:150–240
609:120–200
603:0.8–1.1
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558:200–440
552:1.0–1.4
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2662:PhysOrg
2598:Bibcode
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1391:July 4,
1234:Oceania
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900:dynamos
868:ferrite
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256:removed
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171:yttrium
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864:alnico
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729:cobalt
676:10–40
654:10–88
641:Alnico
324:cobalt
322:, and
320:nickel
175:cobalt
160:coated
156:plated
133:teslas
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113:alloys
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2633:(PDF)
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194:China
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2560:ISBN
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2368:PMID
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1264:The
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866:and
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696:800
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