Query about Blade Material and Such
Hi,

I recently saw a sword from an online website which I am keen to buy ; upon inquiry, the smith provided me the following specs:

Blade : EU 80 Mn 4

Partition-material: EC 235JR EU standard

Pommel: a standard EU 11 SMn 30

Can anyone advice/clarify what exactly are '80 Mn 4', 'EC 235JR EU Standard' and '11 SMn 30' ? Are any of these, especially the blade, equivalent to Carbon Steel?

Thanks in advance :)
Well, googling "Steel eu 80 Mn 4" got me http://www.arcelormittal.com/NA/Products/docu...erview.pdf which describes it as a grade of carbon/alloyed steel for "Unalloyed and alloyed special structural steel for hardening". The others are equally hard to search for. The pommel material, for example, is "High machinability steel not destined to heat treatment".

As for whether that's a good blade material, for sharps or reenactment beaters, that's beyond my knowledge.
"80 Mn 4" is 0.80% carbon and 1% manganese. The 1st number is the carbon content, in % times 100, the next thing is chemical symbols for other elements, and the % content of that element times a magic factor which depends on the element (and is 4 for Mn). This is according to the EN10027-1 standard (and you might find a copy of the standard online if you look).

235JR is a structural steel, and is graded according to its mechanical properties. It's yield strength is 235MPa (the 1st number), and the notch impact test fracture energy is 27J (J means 27J fracture energy, and R means this is tested at a temperature of 20C). Chemical composition is 0.17% carbon, and <1.4% Mn. Basically, mild steel.

11 SMn 30 is 0.11% carbon, 0.3% S, and I don't know how the Mn content is meant to be specified here, but it's about 1%. (If there are multiple numbers separated by hyphens, this is the content of each element in the list, times the magic numbers. Where there are more than 1 element, and only 1 number, I don't know.)

80 Mn 4 is close to 1080 (1080 is only 0.6-0.9% Mn). So, if done right, OK for swords. Higher carbon that many prefer.
~Thank You
Hi Peter, Timo,

Thank you very much for your clarifications and response, especially Timo :)

I'm most delighted they are not scientific names for Stainless Steel, and have proceeded to put up my sword order.

Shall update this thread when I take delivery of the said sword :)
Also close to AISI 1572 structural steel. Carbon seems a bit high for a sword.
Tod Glenn wrote:
Also close to AISI 1572 structural steel. Carbon seems a bit high for a sword.

Care to clarify, Tod? Do you mean EU 80Mn4 is close to AISI 1572, and that it is not suitable to make into a sword?

Thanks.
Yes, 80Mn4 is close to 1572, although the latter has a lower carbon content. It will depend on the heat treat and application, but in general higher carbon means harder steels which aren't as tough. I don't know of 80Mn4 is a deep hardening steel or what Rc your blade maker is tempering to. The comment is just a general observation about the common steels used in sword making. Take it with a grain of salt, or ask you maker his rationale for using this steel if you are worried. Just because it's not a steel commonly used in this application doesn't mean it won't perform well.
80Mn4 will make a nice blade. Not the best steel for a sword as already stated by others, but still good. If the sword is sharp there is nothing to worry about-you are not going to expose the blade to stresses that may potentially break it. If the sword is a training blunt then I personally would go for something tougher, but 80Mn4 would still be pretty good. I used 1080 steel (which is basically same, with just a tad less manganese) for some of my training blades and they held pretty well. And when considering that I am not a bladesmith and didn't have any hi-tech heat treating equipment I would say that they held very well. At the end quality of heat treating would make more difference then the steel itself as long as the steel is suitable.
1080 doesn't deep harden, so you should get a tough core under a hard surface. Depending on the chromium content, 80Mn4 may or may not deep harden. Blade profile also matters. A lot of this of course is conjecture on my part. 80Mn4 is not a steel I've seen in the US. Most swords here are made from 1045, 1060, and 5160 with a smattering of similar spring steels (I've used the last when making swords in the past, with excellent results). Paul Chen uses 9260 IIRC which is a silicon steel reputed to be tougher than 5160, a spring steel best know for its application in automotive leaf springs that also works extremely well for swords. Every maker has their own idea of what steel works best. There was a recent thread about Albion's change. The great thing is that some makers are stepping outside of the traditional steels and can only lead to better swords in the future.

The other thing to keep in mind is that makers tend to use steels that are available, not hideously expensive, reasonable to work with and that have predictable heat treat properties. 1000 series steels tend to be easier to forge and are very forgiving when it comes to heat treat. 5160 is extremely common, is reasonable to work by stock removal once normalized and very easy to heat treat. If marquenched it makes an especially good sword.

In the end, a lot of the characteristics are theoretical anyway, and it's unlikely that the average sword own could tell the difference between swords made of what are admittedly very similar alloys.
On a final note, the design and execution of the blade is just as important as the steel used. The finest steel can by ruined by a poorly designed and built sword. Don't put too much emphasis on the steel, as long as it's a reasonable choice.
Blade Hardening
Tod Glenn wrote:
Yes, 80Mn4 is close to 1572, although the latter has a lower carbon content. It will depend on the heat treat and application, but in general higher carbon means harder steels which aren't as tough. I don't know of 80Mn4 is a deep hardening steel or what Rc your blade maker is tempering to. The comment is just a general observation about the common steels used in sword making. Take it with a grain of salt, or ask you maker his rationale for using this steel if you are worried. Just because it's not a steel commonly used in this application doesn't mean it won't perform well.


Hi Tod, I was told by the smith that the 80Mn4 blade will be hardened to 49 HRC..
That's at the low end of the typical sword made of spring steels. Your smith is probably emphasizing toughness over edge retention. Nothing wrong with that. Typically, swords made from spring steels will be in the 50-53 Rc range. The lower Rc (and not all that low) is probably appropriate given the higher carbon content. Sounds like you maker knows his business.

Looking forward to your review.
Thanks
Thank you very much for so much info., Tod.

I'll be sure to do a review when I get the sword in Sep.

Stay tuned :)

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