Let's start with an original document from Vacuumschmelze, one of the Neumann supplier.
http://www.filedropper.com/1957vacmateriauxmagntiquesdoux20111021
Fra
http://www.filedropper.com/1957vacmateriauxmagntiquesdoux20111021
Fra
BV 08 Transformer Laminations Alloy
- Thread starter BraFra
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Reading the document and some patents of the same age, I've finally understand that the alloy mixture range should be Ni 70-80% and Mo ≤ 5%, now I'm trying to know Cu %, the rest is Fe to balance, with some small quantities of Cr, Mn and Si (Impurities).
micaddict
Well-known member
No useful info from me.
But I think you deserve better than to be alone, so I thought I'd chime in.
Could be a good 'un.
But I think you deserve better than to be alone, so I thought I'd chime in.
Could be a good 'un.
Hi guys, nice Topic.
Sorry I don't understand what document you have to pay?
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Clear. I never seen that document but I'm afraid that doesn't contain "secret" . But let's see
Finally the correct recipe from the other supplier of Neumann, Krupp, as you can see in this document this alloy is under DIN E3 41301 and so is the correct one as indicated in the Neumann BV-08 specs file. In the document, the correct composition and also the correct heat annealing treatment...no secret at all
http://www.filedropper.com/magnifer7904e
Fra
http://www.filedropper.com/magnifer7904e
Fra
i can't see the recipe just the sheet with commercial info. Which material you think is right? Mag 7904?BraFra said:Finally the correct recipe from the other supplier of Neumann, Krupp, as you can see in this document this alloy is under DIN E3 41301 and so is the correct one as indicated in the Neumann BV-08 specs file. In the document, the correct composition and also the correct heat annealing treatment...no secret at all
http://www.filedropper.com/magnifer7904e
Fra
Moby said:i can't see the recipe just the sheet with commercial info. Which material you think is right? Mag 7904?BraFra said:Finally the correct recipe from the other supplier of Neumann, Krupp, as you can see in this document this alloy is under DIN E3 41301 and so is the correct one as indicated in the Neumann BV-08 specs file. In the document, the correct composition and also the correct heat annealing treatment...no secret at all
http://www.filedropper.com/magnifer7904e
Fra
As you can see in the document the Magnifer 7904 is under the DIN E3 41301 and as you can see in this original document from Neumann http://www.filedropper.com/u47trannywinding, the spec about the lamination is that they should be DIN E3 41301, so this is the correct material. In the document is clearly write the recipe Ni 80%, Mo 4.9%, Mn 0.5%, Si 0.3%, C 0.02% and Fe to balance and it respects also what is write in the Vacuumschmelze document. At page 14 it's write about the final annealing treatment. Hope that now it's more clear
Fra
Pip
Well-known member
Hi:
I'm glad to see this started as its own thread. But the filedropper documents are not loading so hard to discuss or follow.
I'm glad to see this started as its own thread. But the filedropper documents are not loading so hard to discuss or follow.
Documents are fine but new Krupp materials are not the same as used in BV8 . Same standard but chemistry is different. Of course, it can be used as replacement but its not mixture from 1950's. If you are looking for that. BTW, I don't have any reason to fool you I'm not producing or selling those
BTW, chemistry differs from VAC
Moby said:
I'm not understanding, in the VAC document from the 1957 is write that the only material under E3 DIN 41301 (so usable for BV08) is the MuMetall A-50 garantie, which in their spec should have Ni 72-80% some parts of Mo, Mn, Si and Cr and Fe to balance, this material was used in the Neumann production. In the same period Neumann also had Krupp as supplier and their "competitor" to MuMetall was called Magnifer 7904 and it have a Ni content in the same range of the VAC and the same elements, and was under the same standard. Now if we are talking in minor difference about Mn, Si and Cr it's ok, but, since Neumann used all the two alloy, in using as BV 08 laminations alloy there is no difference between this two, if you are saying this is like you are saying that since Neumann used all the two over their production we will have different transformer due to the supplier of the stock at the moment. Please could you be clearer? Thanks a lot.
Fra
I'm talking about this. That's not a recipe , thats overall info and it's believe or not used as start point for BV8's lam's chem. Original is custom made and my measuring shows that. Again, it's possible to replace original alloy with modern mixtures and tweak it to same permeability with proper final treatment but it will be still just similar. I have no problem with that, but if we are talking about exact alloy used in original BV8 then we are wrong. So what' the point of this thread? To make something or just to feed users curiosity. If it's curiosity , than yes, you are right. that's it
edit: Yes , Neumann used 2 different alloys (maybe more but I found 2) One is variation of VAC's from 1957 and second is from Krupp but we don't have Krupp's document from 1950's . Just modern one (and mixture inside is partial)
Bra and other users in this topic, why you hide your mail and PM? I have a feeling like talking with ghosts
Of course, i'm talking about that . But I start to talk about that because I wanted to know is the new BV8 made from Austrian guy original or not. If yes why to search for more?poctop said:I like this for sure , a Laser-ARC ICP-Mass-spectrometer and xrf could resolve the questions and myths,
I have acces to ICP Mass spec but ... I need a laser
Best,
Dan,
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