Talk:Ferrite (magnet)

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Could someone add information about history of ferrites - for how long they have been known? —Preceding unsigned comment added by 83.30.185.128 (talk) 18:14, 26 June 2010 (UTC)

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there are many references to nickel and zinc in ferrites. Are these wrong?


rai69:

"Today, they are the most commonly used magnets in radios. The maximum magnetic field B is about 0.35 tesla and the magnetic field strength H is about 30 to 160 kiloampere turns per meter (400 to 2000 oersteds). (Hill 2006)"

Sorry but in my opinion these must be old informations; with actual (2007) numeric values it would be: The maximum magnetic field B is about 0.43 tesla and the magnetic field strength H is about 30 to 360 kiloampere turns per meter (not doped)and B is about 0,44 tesla, H is about 380 kA/m for doped materials.

Maybe, somebody with better command of English than me could change this in the articel.

i hate u all —Preceding unsigned comment added by 195.195.7.61 (talk) 12:57, 3 October 2007 (UTC)

should Chemie.de get a mention, as the majority of this information was ripped off, word for word, from their site? —Preceding unsigned comment added by 193.195.77.146 (talk) 10:36, 4 January 2008 (UTC)

I am quite sure none of this information was "ripped off, word for word" from chemie.de. Amongst other things, chemie.de has no English on it whatsoever; furthermore, I can make out from what litle German I know that the information is not even similar in phrasing and formatting. 75.95.99.15 (talk) 17:17, 29 May 2011 (UTC)

"They are the most commonly used magnets in radios." Huh? Where, exactly? In the speakers? Needs clarification. 209.145.162.138 (talk) 18:03, 14 May 2008 (UTC)bplipschitz

NiZn Chem formula[edit]

i have been looking up ratios of atoms by looking at the chem formulas. it does appear that the NiZn formula is incorrect, unlike the simularity between mixes in hard ferrites of strontium and barium, the MnZn and NiZn are not the same. NiZn is quite approximate being NiZnFe4O4, while the MnZn is a mix of Fe2O2 (52%), MnO (25%) and ZnO (23%), this is an average. the source of my averages are: Wei Zhu, "On Preparation of High Permeability Mn-Zn Ferrite" and the NiZn formula is reasonably common on the 'net though some lack the "O4". i did find another book (Physics for Engineers By M R Srinivasan) to double check once more, that lists them as follows: 48%MnO Fe2O3, 52%ZnO Fe2O3 and 36%NiO Fe2O3, 64%ZnOFe2O3 showing a minor descrepency with the former source. it could just be the lack of available information that has lead people to beleive that NiZn is stoich...Charlieb000 (talk) 00:26, 4 March 2012 (UTC)

Rare properties?[edit]

The article states that ferrite is "one of the few substances that combine these two properties," being both magnetic and electrically insulating. But is this really true? I'm a magnet scientist and I know of all sorts of insulating magnets. Lots of rare earth oxide magnets are both magnetic and insulating, due to the localized 4f orbitals. Same goes for 4d and 5d, I think. I'm going to take out that sentence unless anyone objects. And if you do object, could you find a source that supports the claim or make an argument of why it belongs?Tedsanders (talk) 18:56, 19 June 2015 (UTC)

I actually put that in. I appreciate your bringing up the rare earth oxide magnets; I didn't know that. I guess I wrote that to alert general readers that those two properties are the reason for the widespread use of ferrites. Although I take your point, ferrites are certainly the most common materials which are ferromagnetic and nonconductive; most other common ferromagnetic materials are metals. The combination of those two properties are the reason for soft ferrites' use in the electronics industry. So I'd like to put something in the introduction to that effect. --ChetvornoTALK 19:50, 19 June 2015 (UTC)