Talk:Mu-metal

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Why does the M-1040 link connect to the page for the compound Melatonin? —Preceding unsigned comment added by 24.7.69.210 (talk) 01:20, 19 December 2007 (UTC)[reply]

I'd have to say that Monster Magnet is my favourite... oh, sorry. -Ashley Pomeroy 20:03, 21 August 2005 (UTC)[reply]

More info please

How thick of a sheet of mu-metal would be needed to block an average magnet? Is it feasible to wrap a drawer with mu-metal to protect magnetic tapes? Can you bend and mold mu-metal? There is very little information about the use of mu-metal in this article. --Kainaw ^(talk) 21:08, 8 December 2005 (UTC)[reply]

I have very little experience in actually working with Mu Metal, since all of my stuff is built for me, but I'm under the impression that it is not easy to work with in terms of bending and molding (I believe it's a laminate of many thin layers of slightly different nickel-iron alloys, but I could very well be wrong there). As for thickness, it doesn't take very much: a ~1/16" thick full enclosure will probably attenuate fields by a factor of 100 or so. However, it is a very expensive metal to wrap a drawer in. For less stringent shielding, several companies sell a "foil" version that can be bent. What sort of "average" magnet do you need to protect your tapes from? Most fridge magnets can't harm magnetic media beyond a few centimetres, but if you happen to live beside a quaintly unshielded NMR magnet... Potatophysics 15:40, 15 February 2006 (UTC)[reply]

Yeah, it's probably more cost-effective to line your drawer with sheet steel from the hardware store. Or you could compromise and pry the laminate sheets out of an old transformer, if you're careful about all the nasty halogenated chemicals involved.--Joel 21:32, 8 May 2007 (UTC)[reply]

It's not easy to bend, in my experience. At right angles and flat surfaces it's not too bad. — Omegatron 13:47, 11 May 2007 (UTC)[reply]

Considering the rate at which magnetic field strength drops off over space, it might just be cheaper to make a shelf in a large enough hollow container. Alvis 05:00, 11 September 2007 (UTC)[reply]

Better composition numbers

Right now, the article totals over 100% per the composition of component metals (75% nickel, 15% iron, plus copper and molybdenum). Just how much copper and molybdenum does the final product consist of (and correspondingly less of nickel and iron)? Alvis 04:59, 11 September 2007 (UTC)[reply]

75 + 15 = 90, so I guess that the other two make up most of the remaining 10%. Verbal chat 07:25, 7 October 2008 (UTC)[reply]

One reference (64th ed. CRC Handbook of Chemistry & Physics) gives composition as 18% Fe, 75% Ni, 2% Cr, 5% Cu (and no Mo). Maybe the lead of the article should say that Mu-metal is a range of alloys rather than just an alloy.--Theodore Kloba (talk) 20:36, 29 August 2012 (UTC)[reply]

That's a pretty narrow range; the anomalous magnetic properties occur over only a narrow range of composition. Most sources refer to mu-metal in the singular, in spite of enormous efforts by greedy manufacturers to try to differentiate "their" proprietary formulation from the herd. I think the article should conform to common usage and call mumetal a (singular) alloy. --Chetvorno^TALK 05:11, 30 August 2012 (UTC)[reply]

Discovery?

Could use some information on the history of Mu-metal, discovery, etc. —Preceding unsigned comment added by Morecromulent (talk • contribs) 05:44, 8 April 2008 (UTC)[reply]

Added some. --Chetvorno^TALK 19:45, 14 December 2008 (UTC)[reply]

Reword?

The article says "Its magnetic properties are no better than other high permeability alloys such as Permalloy, but it is more ductile and workable" - but mu-metal has quite a different susceptibility and permeability. Can we change this sentence to reflect that? How about "mu-metal has a higher permeability and susceptibility than Permalloy, but is generally favored over other high permeability alloys because it is more ductile and workable." Tevonic (talk) 18:38, 25 January 2009 (UTC)[reply]

Infobox

Can someone please add a relevant infobox to this page? Stifle (talk) 17:45, 17 March 2012 (UTC)[reply]

Not enought numbers

Writen - "giving it a low coercivity that". how much ? low is not concretely. :( --Zadobroprotivzla (talk) 07:36, 18 April 2012 (UTC)[reply]

Persistent spammer

Just a heads up. User:MuMETAL, apparently a hack for the Magnetic Shield Corporation, has been repeatedly inserting spam into this article over a period of almost a year. They're also getting their spam in other areas of WP, such as blatantly promotional descriptions of images in Commons like this. We should keep an eye on other WP articles that mention mu-metal. --Chetvorno^TALK 22:26, 9 August 2012 (UTC)[reply]

More spam

Lately there has been repeated attempts to insert a link to a vendor site for a proprietary formulation of Mu-metal, Ad-Mu-80, which I have reverted. Perhaps this is because there are existing links to vendors under "External links". I think we need to get rid of all these vendor links, which constitute WP:SPAM. Any useful scientific data on mu-metal which they contain can be found in non-promotional reference books on Google Books; so these spammy information links can be replaced by spam-free links. --Chetvorno^TALK 06:32, 10 February 2013 (UTC)[reply]

Mu-Metal

Copied from User talk:Glrx/Archive 5#Mu-Metal

I feel as if you will allow Co-Netic and Amumetal to be listed as other mu metal materials than Ad-Mu-80 should be listed as well. Co-Netic and Amumetal are other trade names that companies use just like Ad-Mu-80 either they all should be allowed or they all should not. Also my links to our Engineering Catalog and Procurement Catalog get deleted under the extneral links but other companies such as magnetic shield get to keep their links to their brocure? How is this justified? — Preceding unsigned comment added by 199.16.223.2 (talk) 22:55, 10 February 2013 (UTC)[reply]

This topic should be addressed on the Mu-metal and Electromagnetic shielding talk pages (Talk:Mu-metal and Talk:Electromagnetic shielding) so all interested users can participate in the discussion.

What's happened is you've added some material, and other editors have objected to it and removed the material. What's supposed to happen then is a discussion is started on the talk pages. See WP:BRD. If you can garner a consensus for including the edits on the talk page, then the edits go into the article. It's that simple. I'm just a lowly editor here; I am not the arbiter of what goes into articles.

That said, I think you will have a difficult time getting a consensus.

My sense is your purpose is to advertise Ad-Mu-80 and its manufacturer. Wikipedia is not a directory service. It does not intend to inform readers about every manufacturer of every similar product. Right now, I believe the articles list too many commercial names; such lists quickly turn into spam magnets; I'd trim the list more. I haven't checked, but I would not expect an article on soap to list every brand name of soap.

Wikipedia allows external links, but those links should have some encyclopedic purpose. I gave an example of one manufacturer's brochure providing construction details of a zero-gauss chamber. Such chambers are mentioned in the article, and the article should eventually include more detail about them. An external link to a manufacturer's catalog that just lists material properties usually is not the type of information Wikipedia is interested in. I don't see a lot of redeeming value in that link, but I consider your deletion of that link as being WP:POINTy.

Neither is Wikipedia trying to be a reference manual for manufacturers' products. Adding such information would add a lot of detail, but the information would have little benefit to most readers.

Yes, it seems unfair that some materials such as Co-Netic gets mentioned but Ad-Mu-80 does not. As I said earlier, I think the list is too long. However, I have previously come across the term Co-Netic but I have never before encountered Ad-Mu-80. The argument that somebody's product is covered in WP therefore my product should get similar coverage does not follow. Maybe the somebody's product shouldn't be covered in Wikipedia. Maybe Wikipedia doesn't need to cover them all. WP:OTHERSTUFFEXISTS

Wikipedia also wnats independent, secondary, reliable, sources. Manufacturers are primary sources with a vested interest. If you have some independent sources that cover Ad-Mu-80, compare it to other versions of mu-metal, and make some significant observations, then that could reasonably go into the article. If it's just a variation of mu-metal, then it's hard to see how a tradename for a similar material is significant enough to merit mention. I suspect there are many other makers of mu-metal-like materials. WP:DUE

Wikipedia is also leery of editors who have a conflict of interest. Such editors may put their interests above Wikipedia's interests or may just have a skewed perspective. A Wikipedia reader is interested in what the material does, but it's not clear that reader actually wants to know all the manufacturers or even how to order it. I own a lot of chunks of mu-metal, but they are all parts of equipment; I've never ordered any of the stuff myself.

Glrx (talk) 00:07, 11 February 2013 (UTC)[reply]

Weasel word

"which reportedly[2] increases the magnetic permeability about 40 times"

Weasel word "reportedly". Why the weasel? — Preceding unsigned comment added by 71.184.114.179 (talk) 12:03, 20 July 2015 (UTC)[reply]

About history

"...conductive seawater surrounding an undersea cable added a significant capacitance to the cable, causing distortion of the signal" This statement is not correct. Long lines simply had too much inherent capacitance. Transmission line concept was not well developed. Heaviside developed the mathematical formulation and they figured out they had to compensate for the line capacitance to make it a tranmission line with no frequyency limitation - ideally. Someone should correct if I do not get back to it.