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I have already been searching the web and COMSOL for a few hours, but I can't find the B-H curve of structural steel (more specifically S235JR - EN 10025.)

In COMSOL there is a list of nonlinear magnetic materials, further grouped into material types. I assumed that S235JR is either a low carbon steel type or a stainless steel, but I can't make sense of the COMSOL steel names.

Here is stainless steel:

Stainless steel

and here is low carbon steel:

Low Carbon Steel

Which one has similar B-H curves to S235JR?

Alternatively, if anybody can point me to a database with the B-H curve of S235JR, I would be grateful.

JRE
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mss
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    I've found it really tough to find B-H curves for specific materials without paying for it. – DKNguyen Aug 10 '20 at 18:47
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    S235JR is high-manganese, low-carbon structural steel, similar to 1513. Having said that -- I don't know what the manganese does to the B-H curve. If I did, I could make this an answer! If it does nothing, then the stuff will be somewhere between 1010 and 1018 in its properties. – TimWescott Aug 10 '20 at 20:40
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    in cases like this I think you need to break down the list by percent contribution of elements, and just try and find the closest match... Then rely on laboratory testing to improve your model... Or see if someone offers to pay for model. – MadHatter Aug 11 '20 at 01:12

2 Answers2

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According to this reference here the S235JR steel is equivalent to the ASTM A36 steel. I believe that is easy to find information about this ASTM steel.

One option is to look here, but the authors didn't went too far in the saturation point. Another option (I've used it some times) is to download FEMM4.2 (here), install it and check in the material library. Maybe 1008/1020 steel is also not far from A36.

Luiz Oliveira
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While the saturation magnetization is a rather reproducible material specific quantity, the BH curve isn't.

Even for the same alloy, it depends a lot on the manufacturing process and the shape of the material.

Grain size can affect the permeability by several times and a highly asymmetrical piece (e.g. a sheet) can easily have the permeance differ by several orders of magnitude depending on the direction of H through the piece.

tobalt
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  • As sad as it is, I guess I have to accept this answer. I was more or less lucky to obtain the BH curve of a S235JR rod from a colleague. He already told me, that the values would most likely not generalize to my use case, because of the points you mentioned. After simulating the experiment, we did some measurement and found a discrepancy of roughly 10-20% depending on where we measured the B field. – mss Oct 23 '21 at 13:41