Jeffrey LewisRing Magnets

Last month, David Albright published screen shots of a solicitation by an Iranian company for ring magnets that may suitable for centrifuge bearings – a crucial component of Iran’s centrifuges. The question is whether the magnets, which fall below the thresholds established in the NSG “trigger list” are really suitable for Iran’s IR-1 centrifuges or not.

Ferenc Dalnoki-Veress and I have written an analysis comparing the strength of the magnets sought with an effort by Pakistan to produce P2 centrifuges in Germany in 1991.  Our conclusion is that, at least on the issue of magnet strength, the magnets are consistent with a first generation centrifuge like the IR-1.

You can find our reasoning below the jump.

How Many Mega Gauss Oersteds Does It Take to Make Your World Spin?

Ferenc Dalnoki-Veress and Jeffrey Lewis

March 20, 2013

Accusing a foreign individual, entity or government of engaging in illicit commerce relating to the spread of nuclear weapons is a complex issue and must be handled carefully. Ideally, the item in question must match to the known specification of the nuclear-use item. However, buyers often purchase items that don’t precisely match these specifications to circumvent export control regulations. To prevent the sale of these items, the NSG has a “catch-all” provision under which members agree to refrain from exporting even non-controlled goods if there is a reason to believe that it is intended for a nuclear weapons program.

The recent case of an Iranian firm soliciting an order of ring magnets illustrates some of the challenges in controlling dual-use technologies.

Last month, David Albright published a report on the Institute for Science and International Security website suggesting that Iran attempted to purchase 100,000 ring magnets suitable for centrifuge bearings – a crucial component of Iran’s centrifuges (Ring Magnets for IR-1 Centrifuges, February 13, 2013).  Albright posted a screenshot (Figure 3) showing a web inquiry on a Chinese website by Mr. Mohammad Tahmouresi , representing an Iranian trading company called Jahan Tech Rooyan Pars Co., regarding 100,000 ferrite barium strontium ring magnets.  (In 2012, Canada sanctioned Jahan Tech Rooyan Pars Co. for supporting Iran’s “proliferation sensitive” activities.)  Albright also provided a translation of the inquiry, which included some text in Chinese (Figure 4).  Albright, working with an unnamed European government and an ISIS centrifuge expert, concluded that the technical specifications of the ring magnets generally matched those for Iran’s first-generation centrifuges, requiring only minor modifications to the bearing. Albright, citing concerns about proliferation-sensitive information, redacted the dimensions and other technical information that would allow outside experts to assess his conclusions.

Upon closer inspection, however, Albright inadvertently left in a key technical detail relating to the strength of the magnet – that Iran was seeking magnets with a strength (in terms of BHmax) is 3 MGOe. BHmax is an important parameter because the magnet must stabilize the rotor as it spins at hundreds of meters per second. The threshold for controlling magnet exports set by the Nuclear Suppliers Group is much higher than this – 10 mGOe – leading some commentators to question Albright’s assessment.  It is important to note that the thresholds established by the Nuclear Suppliers Group are reached by negotiation and attempt to balance competing interests in restricting the spread of sensitive technologies and permitting normal commerce. This is especially challenging when dealing with technologies, like the IR-1 centrifuge, that are more than thirty years old. Whether this inquiry is plausibly linked to Iran’s centrifuge program depends in part on the possibility that the IR-1 uses ring magnets that fall below the threshold specified by the NSG. If such magnets are unsuitable for Iran’s centrifuges, then we can dismiss the allegation.

As it turns out, we have relatively detailed information about the ring magnets used in Pakistan’s P2 centrifuge because of a failed 1991 effort by Pakistan to purchase similar ring magnets in Germany.  In 1995, Mark Hibbs reported that Pakistan attempted to purchase similar ring magnets from the German firm Magnetfabrik Bonn (MFB) GmbH (see: M. Hibbs, “Siemens Venture Believed Used in Pakistan Centrifuge Quest,” Nuclear Fuel, Aug. 28, 1995).  Hibbs did not report the strength of the magnets, but he did state that Pakistan ordered aluminum-nickel-cobalt (Alnico)-260 S-ring magnets. The numerical suffix “260” is a designation specifically corresponding to the German standard for the technical conditions of materials of permanent magnets (DIN 17410) and corresponds to a (BH)max=18 kJ/m3 or 2.4 MGOe. In correspondence with Hibbs, we were able to confirm that the original specification of the 1991 procurement effort was 18 kJ/m3.

Our conclusion is that, at least on the issue of magnet strength, the magnets are consistent with a first generation centrifuge like the IR-1.

Hibbs also provided a detailed description of the dimensions of the ring magnets:

“Pakistan had first indicated that Telephone Industries sought magnets sized at 52 millimeters in diameter and 8 mm in height, with a ring thickness of 36 mm. It later specified a precise diameter of 52.8 mm and a thickness of 36.8 mm and defined fine tolerance requirements in the range of a few hundredths of millimeters.”

The same dimensions are given in an ISIS report by Albight, Brannan and Stricker. “For example, a P2 ring magnet sought by Iran later has dimensions of 52.8 mm x 36.8 mm x 8mm. P1 ring magnets have similar dimensions.”

It is, of course, possible that the magnets were intended for other purposes. However, we have concluded that from the point of view of the magnetic properties they can also be used for ring magnets for older generation IR-1 centrifuges, which the IAEA has reported Iran still uses in their centrifuge facilities.  This is an important data point that characterizes the item in question as being appropriate for nuclear-use.  Knowing the dimensions of the attempted procurement would shed further light on the issue.

An unanswered question relates to the Canadian sanctions against Jahan Tech Rooyan Pars.  Although Canada stated that the sanctions are the result of Jahan Tech Rooyan Pars having provided “support” to proliferation-sensitive activities in Iran, Canada has not made public a specific allegation about what firm might have done to elicit sanctions.. Further information from the Canadian government could help understand the final end-user for any ring magnets purchased by Jahan Tech Rooyan Pars.


  1. yousaf (History)

    Thank you — a very useful post.

    Quoting: “on the issue of magnet strength, the magnets are consistent with a first generation centrifuge like the IR-1.”

    Yes, a completely correct analysis and in full agreement with my Bulletin piece which states:

    “Although magnets with an energy product of 3 MGO could be consistent with applications in suspension bearings of the older IR-1 centrifuges, they are also consistent with a host of other applications.”


    Being consistent with centrifuge use, of course, does not exclude being consistent with a host of other applications, as you and Ferenc correctly mention — but which ISIS and WaPo unfortunately did not.

    As you quite rightly state: “It is, of course, possible that the magnets were intended for other purposes.”

    A critical point that is missing from the WaPo story which calls these common magnets “highly specialized” — they are not.

    In fact, Iranian companies make such magnets — no need to import them.

    The folks at Jim Lobe’s blog recently asked me to clarify on this very issue:

    =======relevant excerpt below=======

    Q: What do you make of recent claims that Iran may have ordered magnets for its centrifuge program?

    Yousaf Butt: The first thing to note is that there is no evidence of any actual magnets. The Washington Post story mentions “purchase orders” for some ceramic ring magnets but there are no “purchase orders”. The whole story is based upon a web-inquiry someone in Iran allegedly made for 100,000 ceramic ring magnets. So this is a simple mischaracterization. The evidence presented (Figures 3 and 4 in the source report) merely show a web inquiry, but we don’t know whether the supplier had any interest in discussing the question further. Such a web-inquiry is one step above a google-search. There is no mention of money, delivery dates or letters of credit, all of which would be part of a formal “purchase order”.

    The other problem is in jumping to the conclusion that such magnets can only be used for centrifuges. This is a fault both in the source document as well as the news story. Such magnets have a host of other applications, for instance, in loudspeakers, DC motors, in the blower fan units of car radiators, military field telephones, etc. The article characterizes these magnets as “highly specialized” — they are not. They are common magnets. As I mention in my piece in The Bulletin of the Atomic Scientists, “Although magnets with an energy product of 3 MGO could be consistent with applications in suspension bearings of the older IR-1 centrifuges, they are also consistent with a host of other applications.”

    The story is not necessarily completely wrong — it is simply based on very thin evidence (which it exaggerates) and it’s unbalanced because it does not mention the various possible uses of these very common magnets.

    Q: If these magnets are so common why would Iran need to import them?

    Yousaf Butt: Again, there is no evidence that Iran was importing or even trying to import such magnets — there is merely an alleged web-inquiry, possibly to check prices. In fact, Iran can and does make such magnets within the country. For example, the Taban Magnetic Materials Development Co. has a website where they advertise the fact that they “produce ceramic permanent magnet (hard ferrite)”.


    • rwendland (History)

      Taban Magnetic Materials Development Company has a marketing website with a photo of an extensive range of ring magnets they sell. Another marketing website says they were estabilished in 2002, and have a production capacity of 1500 ton / year. Gives location & telephone numbers for them, says they can deign magnets, but unfortunately no specs other than produce “to ISO/TS16949:2002 from NORD TUV” (an automotive quality system). Another website says employs between 51-100 People and have a turnover of US$1 – 2.5 Million, exporting 31% – 40% of product.

      Seems very unlikely the Iranian nuclear industry would need to seek simple magnets on public websites abroad. Why didn’t ISIS mention this?

    • rwendland (History)

      … and I’ve found a published paper about magnetic properties of nickel ferrite nanoparticles in Elsevier’s Journal of Magnetismand Magnetic Materials, co-authored by two Taban Magnetic Materials Development Co employees. I don’t know much about magnets, but this looks like pretty convincing evidence that Taban (and Iran) has significant technical competence in producing magnets:

      Preparation and magnetic studies of nickel ferrite nanoparticles substituted by Sn4+ and Cu2+

      Eghbali Arani, Mohammad; Javad Nasr Isfahani, Mohammad; Almasi Kashi, Mohammad

      Journal of Magnetism and Magnetic Materials, Volume 322, Issue 19, p. 2944-2947. (Received 13 January 2010)

      DOI: 10.1016/j.jmmm.2010.05.010

  2. rwendland (History)

    a) Taban Magnetic Materials Development advertise that they can supply both barium ferrite and strontium ferrite magnet powder (they export it to Turkey), and given the other magnet production info above and below, it is pretty likely they could produce the “ferrite barium strontium ring magnets” ISIS mentions.

    b) Their parent company, Taban Niroo Sepahan Co which is a 1996 heavy engineering (including energy sector) offshoot of Esfahan Steel Co, owning 58% of Taban Magnetic Material Developing, has further info on magnet capability:

    * started on magnets in 1994, and spun of the subsidiary in 2002
    * The first producer of constant ceramic magnet in the Middle East
    * Segment (arc), Ring, Disk, Block, & Other shapes
    * Magnetic Powder production
    * magnetic sediment removing for utilization in boilers, thermal convertors, indoor water heaters
    * magnetic fuel reduction system for automobiles
    * Production of magnetic smithereens in shape of ring, segment, block and others depending on customers need.
    * Production of magnetic powder.

    Main application areas:

    – Car Industries (DC Motors, Loud Speakers, Anti vibrating Insulators for car frame)
    – Electronic Industries (Command circuits, Computer, etc)
    – Home Appliances (Refrigerators door magnets, small motors, etc)
    – Educational purposes.

    One interesting comment is that the parent company has “direct cooperation with QINETIQ CO. (UK) for rendering calibration services in Iran”. Qinetiq is the privatised former research divisions of the UK MOD, once 30% owned by the U.S. Carlyle Group.

    Given Iran seems to have had a significant magnet production capability for many years, the ISIS report would only have been really interesting had it clearly demonstrated the alleged request was for a magnet specification Iran could not produce. It doesn’t do that. Absent that, the report seems to be rather a time waster for people in ACW circles.

    • Jeffrey (History)

      No one is claiming Iran cannot make magnetic powder, but a careful look at publications from the Isfahan University of Technology reveals an ongoing interest in sintering to render the powder in the form of magnets.

      I am guessing our friends at Taban advertise the production of powder but not sintered magnets because they can’t manufacture the latter.

    • A simple test (History)

      Jeffrey: “I am guessing our friends at Taban advertise the production of powder but not sintered magnets because they can’t manufacture the latter.”

      Sorry, Jeffrey, why do you need to guess when you have a simple means of finding out the answer?

      All you need to do is to “post a solicitation” on that same Chinese web site, but address your request to Taban rather than to the Indians.

      If Taban make ring magnets then they will respond to your solicitation with a quote, and an estimate for delivery-time.

    • Jeffrey (History)

      You go ahead and tell us how that goes.

  3. JO (History)

    Their engineers should really have considered the inferior mechanical properties of hard ferrite composite magnets vs. Alnico when trying to fill this part request.

    Indicates low budgets and high management targets.

  4. Dan Joyner (History)

    I won’t substantively address the technical issues here – unlike some, I know my limitations. On the overall narrative, though, isn’t it right to say that this entire incident, about which so much has been written, can be summarized as follows – and here I will assume the technical conclusions reached by Albright and Lewis:

    An Iranian company tried to buy magnets that can be used in Iran’s centrifuges. The company may have been intending to supply these magnets to Iran’s centrifuge program. We don’t know if they ever got the magnets, or if they ever passed them on to Iran’s centrifuge program.

    Isn’t that really the whole story here? If it is, then I’m not really seeing why this is a story of such importance as to merit all this writing about it. And since we don’t know whether any country actually sold magnets to the Iranian company, there is no actual NSG issue here, right?

    And just fundamentally, Iran’s having a uranium enrichment program, and maybe buying magnets abroad to maintain or enhance that enrichment program, isn’t really news is it?

    I think the question of whether Iran has a legal and moral right to have a uranium enrichment program, just like Japan and every other NNWS does, is simple to answer in the affirmative, and that they will maintain this right on the other side of any diplomatic accord that is eventually hammered out regarding their nuclear program. So again, I just don’t see what all the fuss is about over this story.

    • Jeffrey (History)


      You reject the legitimacy of sanctions on Iran. Well, fine. But for the rest of us who don’t, enforcement is a nontrivial issue.

    • Pirouz (History)

      The fuss, Dan, is about a nation from the global south attempting to assert its right under the NPT to the technology of nuclear power including the fuel cycle.

      In case you haven’t noticed, look how much space is taken up here at the Arms Control Wonk blog towards Iran’s nuclear program, a program our own American IC states with confidence doesn’t contain a weapons program;;while U.S. and Western disarmament obligations as well as Israeli proliferation receives a mere fraction of such attention at ACW.

      You better than most should know careers require certain positions to be maintained. Otherwise no globetrotting to fancy destinations for conferences, no paycheck and a severe reduction in status.

    • What's in a word? (History)

      Jeffrey: “You reject the legitimacy of sanctions on Iran.”

      I believe that Dan rejects the LEGALITY of these sanctions, which is an altogether different thing.

      In law “legitimacy” refers to parentage, and so a lawyer (e.g. Dan) would not use that word with reference to sanctions.

      Conversely, to use the word “legitimacy” without reference to parentage (as you have just done) can only mean that you are using that word in its POLITICAL sense.

      And as Russian FM Lavrov has shrewdly pointed out, you need to keep clear in your head that Iran’s nuclear program is perfectly LEGAL even if it is POLITICALLY unacceptable to The Powers That Be.

    • Jeffrey (History)

      You are a douchebag.

  5. Mark Gubrud (History)

    Barium ferrite, strontium ferrite, and barium strontium ferrite are three different types of material.

    Another advertisement by Taban indicates that they do produce finished ferrite products. Sintering is not high technology; it involves only heating and pressing the powder in a mold with some time schedule.

    However, the list of ferrite powders produced by Taban that rwendland provided us includes only barium and strontium ferrites, none of which is listed as having BH above 1.2 MGOe whereas the requirement for the ring magnets stated in the Iranian enquiry is 3 MGOe.

    Given the coincidence of 10 out of 12 digits of the dimensions specified in the Iranian enquiry with the dimensions known for the IR-1 magnets, the only reasonable possibilities are that the “Iranian enquiry” is a fake planted by you-guess-who, or that it is an enquiry seeking to buy magnets for centrifuges.

    However, the latter would only demonstrate Iran’s continuing interest in doing exactly what it said it would do, i.e. build 50,000 centrifuges (enough to fill the Natanz halls), which would be suitable for the production of either LEU or HEU (or both).

    • Jeffrey (History)

      This is what amazes me. No one disputes the Iranians want to build 50,000 centrifuges including the Iranians themselves.

      We are having a debate about whether to bomb them over it (I say we should not), but that debate shouldn’t poison the discussion of this procurement.

      On the question of a provocation, I’ve been spending a ton of time thinking about the role of forgeries and provocations, especially by the KGB in the Cold War. It’s an interesting trick to balance between being naive and paranoid. I don’t have any simple answers.

    • JO (History)

      The properties of these magnets are rather unsuitable. They would be useless in motors under heat loading. Refrigerator magnets spring to mind.

      (Taken from another supplier’s page):
      “..have normal operating capabilities between -40°C and +250°C. As temperature increases, remanence decreases by 0.2%/°C whereas coercivity increases by 0.3%/°C. ”

      That amounts to a warning, ie. for non-stressed applications only. Whats the temperature UF6 has to be kept above?

  6. John (History)

    Really? The intricacies of these tech details are fun and all, but please have a look at the evidence presented: in the original I.S.I.S. document one sees an open web request to get information on magnets. Is this the way a secretive operation would operate? I have strong doubts. Seems either an instance of planted “evidence” or simply a request unrelated to matters nuclear.

    Were this a true surreptitious nuclear-related attempt an Iranian procurement agent would be sent to China/India or else at least called them on the phone — not the web! But it would appear Iran can make this stuff in-house so why the bother? There was also a 2011 News report (albeit Fox) on the Taba site where it was reported centrifuge parts, including the ever so dangerous ring magnets were made.

    • Jeffrey (History)

      Actually, no.

      The Indians use a public procurement process to find controlled items. Remember, these magnets fall below the threshold in the NSG trigger list. A careless or greedy supplier might very well look the other way, especially since the Canadian sanctions on the firm may not be well known.

  7. John (History)

    Perhaps you answered another question.

    Yes, of course, the Indians may supply such magnets (but not the particular company mentioned by I.S.I.S. since it appears to be far too small), but that has to do with normal business greed: not because anything illicit is going on. As you and your coauthor mention there are plenty of uses for such magnets so why should not the Indians supply such magnets? There appears to be an unfounded presumption of guilt. Now, there is indeed a separate issue that Iran *now* has sanctions and magnets, as well as TVs and dish-soap is all sanctioned.

    The NSG *properly* does not designate these magnets as controlled else they would have to pretty much stop a large segment of legal magnet trade. They did think about all this, of course.

    Also we have no idea why the Canadians snactioned the Iranian company: was it because of this very magnet issue? — in which case we are in a circular argument a la Iraq: “They must be guilty on this magnet issue because the Canadaians said they are bad company — why did they say so? Because of the magnets…”

    Anyhoo, the issue I raised was quite separate: that the Iranians, were they really up to something fishy would probably not use a highly traceable web mechanism for procurement for their secretive nuclear program — quite aside from the other honestly very strange things with the query, as mentioned in the Bulletin article you linked to. Also here is the FOX news report saying Iran can make such magnets:

    This in addition to the other magnet company mentioned in the comments above — there may also be magnet companies in Iran without websites.

    The Washington Post and I.S.I.S. should have been far more careful than they have been.

    Today’s Wall St. Journal report by Mr. Albright does not do much to bolster my view of him as an unbiased source in all this.

    • Jeffrey (History)

      I directly answered your assertion by noting that India, for example, uses a public tender process to acquire goods for what you call fishy purposes. (It’s own centrifuge program. I am leaving the Indian firm out of this, since there is no evidence it did, or even could have done, anything wrong.)

      I further noted that an Iranian firm might conclude it could best disguise an illicit procurement by making it appear to be a normal transaction if the items fall below the NSG trigger list threshold, as these magnets do. The Iranians might then count on an either careless or greedy supplier to supply the goods, despite the “catch all” provisions that ought to be in export controls of any NSG member. (I don’t happen to know, at the moment, precisely what India’s export controls say on the matter as it is not an NSG member, but is attempting to join.)

      And, in the event they are caught, the Iranians can surely count on legions of apologists leaping to their defense to claim a sanctioned entity that attempted to procure ring magnets that just happen to be the correct size and strength for IR-1s must be doing so for some totally innocent purpose because we all know Iran isn’t building a nuclear weapons, but if it were that would be Israel’s fault.

      I apologize I wasn’t crystal clear in my first comment. I was treating you like an unbiased observer, which was clearly a mistake.