345:
20:
697:
404:
have moved as far as they can, and the domains are as aligned as the crystal structure allows them to be, so there is negligible change in the domain structure on increasing the external magnetic field above this. The magnetization remains nearly constant, and is said to have saturated. The domain
695:, Yoshihiro Hamakawa, Hisashi Takano, Naoki Koyama, Eijin Moriwaki, Shinobu Sasaki, Kazuo Shiiki, "Thin film magnetic head having at least one magnetic core member made at least partly of a material having a high saturation magnetic flux density", issued 1992
429:
necessary for high power production, they must have large magnetic cores. In applications in which the weight of magnetic cores must be kept to a minimum, such as transformers and electric motors in aircraft, a high saturation alloy such as
525:
In some audio applications, saturable transformers or inductors are deliberately used to introduce distortion into an audio signal. Magnetic saturation generates odd-order harmonics, typically introducing third and fifth
383:
is applied to the material, it penetrates the material and aligns the domains, causing their tiny magnetic fields to turn and align parallel to the external field, adding together to create a large magnetic field
472:
distortion. To prevent this, the level of signals applied to iron core inductors must be limited so they don't saturate. To lower its effects, an air gap is created in some kinds of transformer cores. The
504:. Varying the current in the control winding moves the operating point up and down on the saturation curve, controlling the alternating current through the inductor. These are used in variable
492:. When the primary current exceeds a certain value, the core is pushed into its saturation region, limiting further increases in secondary current. In a more sophisticated application,
266:
293:
215:
732:
379:
are oriented in random directions, effectively cancelling each other out, so the net external magnetic field is negligibly small. When an external magnetizing field
477:, the current through the winding required to saturate the magnetic core, is given by manufacturers in the specifications for many inductors and transformers.
310:
Different materials have different saturation levels. For example, high permeability iron alloys used in transformers reach magnetic saturation at 1.6โ2.2
760:
421:
of around 2 T, which puts a limit on the minimum size of their cores. This is one reason why high power motors, generators, and
691:
622:
375:
that can change their direction of magnetization. Before an external magnetic field is applied to the material, the domains'
162:
736:
823:
676:
647:
597:
449:
when the current through them is large enough to drive their core materials into saturation. This means that their
480:
On the other hand, saturation is exploited in some electronic devices. Saturation is employed to limit current in
461:
180:
785:
223:
869:
97:
more or less levels off. (Though, magnetization continues to increase very slowly with the field due to
692:
413:
Saturation puts a practical limit on the maximum magnetic fields achievable in ferromagnetic-core
668:
515:
401:
874:
271:
186:
711:
141:
curve) of a substance, as a bending to the right of the curve (see graph at right). As the
589:
501:
8:
839:
539:
527:
458:
296:
344:
565:
508:
497:
438:
121:
and their alloys. Different ferromagnetic materials have different saturation levels.
819:
672:
643:
618:
593:
493:
489:
519:
505:
422:
318:
469:
368:
326:
307:
to a maximum, then as it approaches saturation inverts and decreases toward one.
454:
446:
376:
367:
Ferromagnetic materials (like iron) are composed of microscopic regions called
362:
299:. The permeability of ferromagnetic materials is not constant, but depends on
173:
106:
102:
83:
42:
153:, the saturation level for the substance. Technically, above saturation, the
863:
457:
this is usually considered an unwanted departure from ideal behavior. When
426:
414:
389:
158:
98:
90:
32:
314:
793:
485:
418:
27:
450:
138:
37:
23:
Magnetization curves of 9 ferromagnetic materials, showing saturation.
19:
396:, the more the domains align, yielding a higher magnetic flux density
544:
500:
use a DC current through a separate winding to control an inductor's
431:
150:
75:
65:
50:
303:. In saturable materials the relative permeability increases with
465:
442:
425:
transformers are physically large; to conduct the large amounts of
334:
755:
753:
352:
of a ferromagnetic substance reaches a maximum and then declines
750:
372:
118:
114:
60:
55:
453:
and other properties vary with changes in drive current. In
464:
are applied, this nonlinearity can cause the generation of
93:
of the material further, so the total magnetic flux density
165:
smaller than the ferromagnetic rate seen below saturation.
110:
82:
is the state reached when an increase in applied external
400:. Eventually, at a certain external magnetic field, the
733:"Mumetal is one of a family of three Nickel-Iron alloys"
388:
which extends out from the material. This is called
274:
226:
189:
405:
structure at saturation depends on the temperature.
287:
260:
209:
638:Laughton, M. A.; Warne, D. F., eds. (2003). "8".
530:distortion to the lower and mid frequency range.
861:
612:
488:, and ferroresonant transformers which serve as
348:Due to saturation, the magnetic permeability ฮผ
637:
392:. The stronger the external magnetic field
840:"The Benefits of Harmonic Distortion (HMX)"
567:Theory and Calculation of Electric Circuits
168:The relation between the magnetizing field
813:
662:
617:. Technical Publications. pp. 3โ31.
579:
577:
563:
792:. Elliott Sound Products. Archived from
656:
343:
18:
786:"Transformers - The Basics (Section 2)"
663:Chikazumi, Sลshin (1997). "table 9.2".
583:
157:field continues increasing, but at the
129:Saturation is most clearly seen in the
862:
574:
564:Steinmetz, Charles (1917). "fig. 42".
261:{\displaystyle \mu _{r}=\mu /\mu _{0}}
179:can also be expressed as the magnetic
101:.) Saturation is a characteristic of
640:Electrical Engineer's Reference Book
814:Choudhury, D. Roy (2005). "2.9.1".
783:
408:
13:
761:"Magnetic properties of materials"
149:field approaches a maximum value
16:Feature of some magnetic materials
14:
886:
613:Bakshi, V.U.; U.A.Bakshi (2009).
588:. AN IEEE Press Classic Reissue.
445:with ferromagnetic cores operate
790:Beginner's Guide to Transformers
514:Saturation is also exploited in
832:
807:
777:
735:. mumetal.co.uk. Archived from
725:
704:
685:
642:(Sixteenth ed.). Newnes.
631:
606:
557:
356:
124:
1:
584:Bozorth, Richard M. (1993) .
550:
511:, and power control systems.
615:Basic Electrical Engineering
7:
533:
482:saturable-core transformers
10:
891:
818:. Prentice-Hall of India.
816:Modern Control Engineering
360:
329:alloys saturate at 1.2โ1.3
784:Rod, Elliott (May 2010).
665:Physics of Ferromagnetism
494:saturable core inductors
288:{\displaystyle \mu _{0}}
210:{\displaystyle \mu =B/H}
337:saturates at around 0.8
161:rate, which is several
516:fluxgate magnetometers
353:
289:
262:
211:
71:
712:"Shielding Materials"
371:, that act like tiny
361:Further information:
347:
290:
263:
219:relative permeability
212:
145:field increases, the
22:
272:
224:
187:
89:cannot increase the
870:Magnetic hysteresis
540:Magnetic reluctance
498:magnetic amplifiers
441:, transformers and
439:electronic circuits
321:saturate at 0.2โ0.5
297:vacuum permeability
163:orders of magnitude
131:magnetization curve
109:materials, such as
520:fluxgate compasses
490:voltage regulators
475:saturation current
354:
285:
258:
207:
72:
844:Audient Help Desk
624:978-81-8431-334-5
545:Permendur/Hiperco
506:fluorescent light
373:permanent magnets
882:
854:
853:
851:
850:
836:
830:
829:
811:
805:
804:
802:
801:
781:
775:
774:
772:
771:
766:. unlcms.unl.edu
765:
757:
748:
747:
745:
744:
729:
723:
722:
720:
719:
708:
702:
701:
700:
696:
689:
683:
682:
660:
654:
653:
635:
629:
628:
610:
604:
603:
590:Wiley-IEEE Press
581:
572:
571:
561:
434:is often used.
409:Effects and uses
369:magnetic domains
340:
332:
324:
313:
294:
292:
291:
286:
284:
283:
267:
265:
264:
259:
257:
256:
247:
236:
235:
216:
214:
213:
208:
203:
890:
889:
885:
884:
883:
881:
880:
879:
860:
859:
858:
857:
848:
846:
838:
837:
833:
826:
812:
808:
799:
797:
782:
778:
769:
767:
763:
759:
758:
751:
742:
740:
731:
730:
726:
717:
715:
714:. K+J Magnetics
710:
709:
705:
698:
690:
686:
679:
669:Clarendon Press
661:
657:
650:
636:
632:
625:
611:
607:
600:
582:
575:
562:
558:
553:
536:
470:intermodulation
455:linear circuits
411:
377:magnetic fields
365:
359:
351:
338:
330:
322:
311:
279:
275:
273:
270:
269:
252:
248:
243:
231:
227:
225:
222:
221:
199:
188:
185:
184:
127:
70:
17:
12:
11:
5:
888:
878:
877:
872:
856:
855:
831:
824:
806:
776:
749:
724:
703:
684:
677:
655:
648:
630:
623:
605:
598:
586:Ferromagnetism
573:
570:. McGraw-Hill.
555:
554:
552:
549:
548:
547:
542:
535:
532:
415:electromagnets
410:
407:
363:Ferromagnetism
358:
355:
349:
282:
278:
255:
251:
246:
242:
239:
234:
230:
206:
202:
198:
195:
192:
174:magnetic field
151:asymptotically
126:
123:
84:magnetic field
69:
68:
63:
58:
53:
48:
45:
43:tungsten steel
40:
35:
30:
24:
15:
9:
6:
4:
3:
2:
887:
876:
875:Audio effects
873:
871:
868:
867:
865:
845:
841:
835:
827:
825:81-203-2196-0
821:
817:
810:
796:on 2019-07-21
795:
791:
787:
780:
762:
756:
754:
739:on 2013-05-07
738:
734:
728:
713:
707:
694:
688:
680:
678:0-19-851776-9
674:
670:
666:
659:
651:
649:0-7506-4637-3
645:
641:
634:
626:
620:
616:
609:
601:
599:0-7803-1032-2
595:
591:
587:
580:
578:
569:
568:
560:
556:
546:
543:
541:
538:
537:
531:
529:
523:
521:
517:
512:
510:
507:
503:
499:
495:
491:
487:
483:
478:
476:
471:
467:
463:
460:
456:
452:
448:
444:
440:
435:
433:
428:
427:magnetic flux
424:
420:
416:
406:
403:
399:
395:
391:
390:magnetization
387:
382:
378:
374:
370:
364:
346:
342:
336:
328:
320:
317:(T), whereas
316:
308:
306:
302:
298:
280:
276:
253:
249:
244:
240:
237:
232:
228:
220:
204:
200:
196:
193:
190:
182:
178:
175:
171:
166:
164:
160:
156:
152:
148:
144:
140:
136:
133:(also called
132:
122:
120:
116:
112:
108:
107:ferrimagnetic
104:
103:ferromagnetic
100:
99:paramagnetism
96:
92:
91:magnetization
88:
85:
81:
77:
74:Seen in some
67:
64:
62:
59:
57:
54:
52:
49:
46:
44:
41:
39:
36:
34:
33:silicon steel
31:
29:
26:
25:
21:
847:. Retrieved
843:
834:
815:
809:
798:. Retrieved
794:the original
789:
779:
768:. Retrieved
741:. Retrieved
737:the original
727:
716:. Retrieved
706:
687:
664:
658:
639:
633:
614:
608:
585:
566:
559:
524:
513:
481:
479:
474:
436:
419:transformers
412:
402:domain walls
397:
393:
385:
380:
366:
309:
304:
300:
218:
181:permeability
176:
169:
167:
159:paramagnetic
154:
146:
142:
134:
130:
128:
94:
86:
79:
73:
47:magnet steel
693:USA 5126907
486:arc welding
447:nonlinearly
357:Explanation
125:Description
78:materials,
28:sheet steel
864:Categories
849:2020-07-16
800:2011-03-17
770:2016-03-16
743:2013-05-07
718:2013-05-07
551:References
484:, used in
451:inductance
139:hysteresis
80:saturation
38:cast steel
502:impedance
466:harmonics
443:inductors
432:Permendur
327:amorphous
277:μ
250:μ
241:μ
229:μ
191:μ
137:curve or
66:magnetite
51:cast iron
534:See also
528:harmonic
509:ballasts
335:Mu-metal
325:T. Some
319:ferrites
268:, where
172:and the
76:magnetic
462:signals
423:utility
295:is the
217:or the
822:
699:
675:
646:
621:
596:
339:
331:
323:
315:teslas
312:
119:cobalt
115:nickel
61:cobalt
56:nickel
764:(PDF)
820:ISBN
673:ISBN
644:ISBN
619:ISBN
594:ISBN
518:and
496:and
468:and
417:and
111:iron
105:and
437:In
341:T.
333:T.
866::
842:.
788:.
752:^
671:.
667:.
592:.
576:^
522:.
459:AC
183::
135:BH
117:,
113:,
852:.
828:.
803:.
773:.
746:.
721:.
681:.
652:.
627:.
602:.
398:B
394:H
386:B
381:H
350:f
305:H
301:H
281:0
254:0
245:/
238:=
233:r
205:H
201:/
197:B
194:=
177:B
170:H
155:B
147:B
143:H
95:B
87:H
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
