Discussion about acquiring high permeability ferrites for plasma experiments

Author Topic: Discussion about acquiring high permeability ferrites for plasma experiments (Read 272 times)

Chet K	Discussion about acquiring high permeability ferrites for plasma experiments « on: 2026-08-14, 13:49:21 »
Group: Ambassador Hero Member Posts: 4751	Here some suggestions for sourcing such materials . **Topic under construction while information is added on some suggested vendors.••

Peterae

Re: Discussion about acquiring high permeability ferrites for plasma experiments « Reply #1 on: 2026-08-15, 19:44:22 »

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Ok passing a message on from Mark via Chet

You can see model FN200 has a permeability of 2000 and its spells out the other characteristics see attached image.

this is a webpage you can use to send enquiries to over 300 manufacturers and the drawing you sent would be good to show them
https://www.made-in-china.com/quality-china-product/productSearch?word=ferrite+rod+u2000&bv_id=1jvkn8ouba5e&pbv_id=
They all speak great english
My people in China do not specialize in Magnetic materials but are willing to help one to identify the supplier that meets your needs
There are thousands of suppliers not just 300

Discussion about acquiring high permeability ferrites for plasma experiments

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« Last Edit: 2026-08-16, 00:13:53 by Chet K »

Chet K

Re: Discussion about acquiring high permeability ferrites for plasma experiments « Reply #2 on: 2026-08-16, 00:05:25 »

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Peter
thanks for posting that information from Mark Dansie ,
Below is screenshot of the spec sheet/information (CMD5005) from one vendor I contacted at Verpies suggestion in US

So CMD5005 are the specs we are aiming for as we find sources in Marks links !
Here the complete spec sheet on one alternative ferrite .

Page 04 has the overview of their ferrites

Page 15 has the specifics on this FN200 ferrite ( mentioned in previous post.)

https://ferrite.ru/upload/iblock/056/zeeewjiglt6szh3gb20r2tw16tje8a16/New%20Catalog%20of%20Careful.pdf

Respectfully
Chet K
PS
these materials are for the spider core experiments which Itsu has started to build and we need some high permeability ferrite components to complete .
A dedicated thread for this will be hosted in itsu’s bench.

httpsmagneticsgroup.comwp-contentuploads201909CMD5005-ISO-WEB-DATA.pdf.png

Discussion about acquiring high permeability ferrites for plasma experiments

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Verpies

Re: Discussion about acquiring high permeability ferrites for plasma experiments « Reply #3 on: 2026-08-16, 05:33:45 »

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Quote from: Chet K on 2026-08-16, 00:05:25

...and we need some high permeability ferrite components to complete .

High permeability is desirable but so is the lack of degradation of this permeability at higher frequencies.
Also, in order to carve out a monolithic spider shape without air-gaps requires a huge chunk of ferrite. The maximum manufactured chunk size (before they cut it up) is an information that only the OEMs know and it is very hard to come by.

Chet K

Re: Discussion about acquiring high permeability ferrites for plasma experiments « Reply #4 on: 2026-08-16, 15:56:56 »

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Quote from: Verpies on 2026-08-16, 05:33:45

Also, in order to carve out a monolithic spider shape without air-gaps requires a huge chunk of ferrite. The maximum manufactured chunk size (before they cut it up) is an information that only the OEMs know and it is very hard to come by.

Verpies,
Hopefully this coming week will show a path towards these OEM’s…so as to get some quotes on a monolithic chunk appropriate to the task .
Mark D gives the impression there are many more than the link he forwarded !

What would be a good size for the spider core blank ?
And should we consider submitting a spider core rendering … for a quote on finished monolithic core ?

At the moment this center core piece is on the list .
And toroid size for arms ( prior to machining)

To note above is for possibility of building on a budget ( as Itsu has started) , and also there was mention of soft iron .03 mm(?) Enameled wire,
Bundled to the required spider core shape ?( for cost savings and getting more access to experimenters.

Discussion about acquiring high permeability ferrites for plasma experiments

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Verpies

Re: Discussion about acquiring high permeability ferrites for plasma experiments « Reply #5 on: 2026-08-16, 16:49:14 »

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Quote from: Chet K on 2026-08-16, 15:56:56

What would be a good size for the spider core blank ?

A 6" cube.

Quote from: Chet K on 2026-08-16, 15:56:56

And should we consider submitting a spider core rendering … for a quote on finished monolithic core ?

We could but it would raise some eyebrows.

Quote from: Chet K on 2026-08-16, 15:56:56

At the moment this center core piece is on the list .
And toroid size for arms ( prior to machining)

Yes because it is easier to obtain.

Quote from: Chet K on 2026-08-16, 15:56:56

To note above is for possibility of building on a budget ( as Itsu has started) , and also there was mention of soft iron .03 mm(?) Enameled wire,
Bundled to the required spider core shape ?( for cost savings and getting more access to experimenters.

Yes, a bundled enameled fine iron wire would be the poor man's substitute for a ferrite.

Magluvin

Re: Discussion about acquiring high permeability ferrites for plasma experiments « Reply #6 on: 2026-08-16, 18:39:26 »

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"a 6inch cube"

there are now 5 axis desk top machines. read an article that it is the new thing and believe it will hit big like 3d printers.

some are $10k and under. but not completely out of reach.

https://www.amazon.com/Carvera-Desktop-Enclosed-Closed-Loop-Engraving/dp/B0F7LJ66BW/ref=mp_s_a_1_1_sspa?adgrpid=1334809614568020&dib=eyJ2IjoiMSJ9.fJWGxXBQtIw-hq_R5nVzE5tIU9yy4RQaRBlxL8Il4IDKsY6M8SjighJtwcALIXqbbTXtjYq6kwZsnvbccN_XvwL2z7C6nBFctMtH6lOCHBjQvItzIHQipa34Gp4R9-PbCgUtIhxOnPavUh2SOPdOy2prp6KOdhh8oo5TZKK5VKzTGTIpO2nfoSM9V3E_uLzgVFCDW6wWxRXpXb9J_C_KZw.MVygG-3se-nXRL8HIPUthZ3wVk-6LOJmbfvIhZVYpAM&dib_tag=se&gb=2&hvadid=83425875936026&hvbmt=be&hvdev=m&hvexpln=0&hvlocphy=71543&hvnetw=o&hvocijid=12454474134621764877--&hvqmt=e&hvtargid=kwd-83426733394048%3Aloc-190&hydadcr=20373_13325337&keywords=desktop+cnc+5+axis&mcid=8195aa6d2fbe3883945e9a754f0eb4b9&qid=1786901764&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9waG9uZV9zZWFyY2hfYXRm&psc=1

mags

Magluvin	Re: Discussion about acquiring high permeability ferrites for plasma experiments « Reply #7 on: 2026-08-16, 18:42:40 »
Group: Mad Scientist Hero Member Posts: 1246	metglass makes a tape or say bendable strips. make a plan and form a spider core with it. mags

Magluvin	Re: Discussion about acquiring high permeability ferrites for plasma experiments « Reply #8 on: 2026-08-16, 19:53:43 »
Group: Mad Scientist Hero Member Posts: 1246	https://metglas.com/magnetic-materials/ the cost of having to make such a core via machining and cost of materials, this plus time to cut and configure i would say it could be a great core. mags

Chet K

Re: Discussion about acquiring high permeability ferrites for plasma experiments « Reply #9 on: 2026-08-16, 22:09:22 »

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Quote from: Magluvin on 2026-08-16, 19:53:43

https://metglas.com/magnetic-materials/

the cost of having to make such a core via machining and cost of materials, this plus time to cut and configure i would say it could be a great core.

mags

I remember this being discussed earlier ( somewhere)
The characteristics of laminations were not lining up with Device requirements for the best possible results, and I remember being perplexed as to the recommendation of an inexpensive.03mm soft enameled iron wire “was” acceptable…. Apparently soft iron (.03 mm ( bundled)) has properties which are quite interesting and appropriate for this Spider core.. and other (Hubbard ,Mag-vid and (a few others I can’t recall ATM))
Chet

Verpies	Re: Discussion about acquiring high permeability ferrites for plasma experiments « Reply #10 on: 2026-08-17, 15:13:40 »
Group: Administrator Hero Member Posts: 4862	Quote from: Magluvin on 2026-08-16, 18:42:40 metglass makes a tape or say bendable strips. make a plan and form a spider core with it. A tape will not mesh in the center post without air gaps. The center post cannot be composed of parallel planar layers. Metglass tape is very brittle. It's name does not contain the word "glass" for nothing.

Magluvin	Re: Discussion about acquiring high permeability ferrites for plasma experiments « Reply #11 on: 2026-08-17, 15:26:46 »
Group: Mad Scientist Hero Member Posts: 1246	Quote from: Verpies on 2026-08-17, 15:13:40 A tape will not mesh in the center post without air gaps. The center post cannot be composed of parallel planar layers. Metglass tape is very brittle. It's name does not contain the word "glass" for nothing. well if 'glass' is non magnetic, what is the material mixed with it that is? mags

Grumage	Re: Discussion about acquiring high permeability ferrites for plasma experiments « Reply #12 on: 2026-08-17, 19:50:25 »
Group: Renaissance Man Hero Member Posts: 3123	Could a 3Dprinted hollow form be produced and filled with a suitable mixture of materials to suit the experiment? Happy to print off some forms if required. Cheers G. --------------------------- Nanny state ? Left at the gate !!

Verpies

Re: Discussion about acquiring high permeability ferrites for plasma experiments « Reply #13 on: Today at 00:25:57 »

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Quote from: Magluvin on 2026-08-17, 15:26:46

well if 'glass' is non magnetic, what is the material mixed with it that is?

It is not mixed with anything non-metallic. It is a pure ferrous alloy that has been chilled so quickly that it did not have the time to crystallize. The resulting structure is amorphous - like glass.

The way this is usually done is by pouring a thin stream of molten metal on the outside of a rapidly rotating silver drum chilled with liquid nitrogen (or LH) from inside and thus forming a thin flat strip of Metglass with irregular edges that are trimmed later.. Silver's excellent thermal conductivity absorbs the heat out of the molten metal so quickly that it does not have the time to crystallize. The best results occur in vacuum because the chilled silver surface of the drum accumulates frost from the air, otherwise. When the molten metal hits it, frost flashes to steam and ruptures the forming strip and inhibits fast heat absorption by the chilled silver surface.

Verpies

Re: Discussion about acquiring high permeability ferrites for plasma experiments « Reply #14 on: Today at 00:35:43 »

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Quote from: Grumage on 2026-08-17, 19:50:25

Could a 3Dprinted hollow form be produced and filled with a suitable mixture of materials to suit the experiment? Happy to print off some forms if required.

You could cast that shape without a problem.
You could even use the same ferrous alloys that Metglass uses (e.g.: Fe₈₀B₂₀, Fe₇₈Si₉B₁₃, Fe₆₇Co₁₈B₁₄Si₁, Fe₆₆Co₁₈B₁₄Si₂, Co₆₆Fe₄Mo₂Si₁₆B₁₂, Fe₄₀Ni₄₀Mo₄B₁₈, etc...) but the excellent magnetic properties of these alloys are not manifested without the rapid freezing.

Even if you could somehow rapid-freeze the melt, it would not work at higher frequencies because of eddy currents developing in it due to the bulk conductivity of these alloys.
That is why non-conductive ferrites or fine enameled iron wire bundles are required to eliminate the undesirable eddy currents. Enameled Metglass wire bundles would be the best but such things are not manufactured anywhere.