Modern Steel equivalent to Japanese Tamahagane

[Shimmer]

Tamahagane Composition

C: 1.00% to 1.42%
P: 0.013% - 0.042%
S: 0.006% -0.008%
Mn: 0.006% - 0.11%
V: 0.004% - 0.015%
Al: 0.003% - 0.02%
T: 0.003% - 0.0267%
C: 0.69% - 1.54%
Mo: 0.04%
Si: 0.018% - 0.02%



Numerous modern steels have been touted as having a similar composition as Tamahagane including White Steel No.1, 1065, K990, 1070/1075.

However, I believe that the steel with the closest chemical make up to traditional Tamahagane is the French tool steel 100WC10.


100WC10 Composition

C: 1.15
P: 0.018%
S: 0.008%
Mn: 0.38%
V: 0.00%
Al: Not listed
T: Not listed
C: 0.00%
Mo: 0.02%
Si: 0.38%



The problem is I have no idea where to source 100WC10. Does anyone have any insight?

 

[mainaman]

I have been told that Iwasaki formulated his famous swedish carbon steel that Shigefusa and Heiji use to be very close to Tamahagane in properties.

 

[JBroida]

i wouldnt say so much that he formulated it, but he does say that it is similar. When i was meeting with him we took various steels to a grinder to see how they reacted and felt. The difference in spark patterns makes it pretty obvious. We tested tamahagane, the swedish carbon steel he loves, a 200 year old nail forged out of god knows what, and some more modern types of carbon steel. The Tamahagane and swedish carbon are by far the closest. Here's a picture of what i'm talking about (one the left is the swedish steel and on the right is tamahagane... the hands are Iwasaki-san):

 

[Shimmer]

Which Swedish steel is he using?

I've read that Iwasaki's steel has a carbon content of 1.25%-1.35%.

 

[Eamon Burke]

It may just be me, but those two might well be similar in properties when treated and handled correctly, but they do not look like a similar make up to me. Plus there's some wide tolerances in the Tamahagane there.

 

[mainaman]

i wouldnt say so much that he formulated it, but he does say that it is similar.

May be his father then, he was a metallurgist by education right?

 

[JBroida]

May be his father then, he was a metallurgist by education right?

my understanding is that they tested many types of steel from various makes and found this one to have properties most like what they were looking for. Both Iwasaki-san and his father are/were extremely well educated in metallurgy. I believe both studied at Tokyo University as well.

Actually, Sara and I just finished reading a book written by the elder Iwasaki-san on sharpening... to say that guy knew a lot is a complete understatement

 

[UglyJoe]

It may just be me, but those two might well be similar in properties when treated and handled correctly, but they do not look like a similar make up to me. Plus there's some wide tolerances in the Tamahagane there.

Of course; it's tamahagane. By the method whereby it is created it has a very wide range of, well, everything... hardness, composition, use, etc. When sword makers get raw tamahagane they sort them by hitting them. Those that break and shatter get moved to a "hard" pile and those that bend and move get moved to a "soft" pile. Unlike modern steel tamahagane requires the maker to be extremely precise in his folding and forge-welding operation, as it has a high content of harmful impurities as well as being basically unworkable structurally in it's raw form. The experienced maker is able to take the raw bits, sort them correctly, forge weld and fold them till he gets a useable bar (usually bars of hard steel and bars of soft), then move on from there. I've wanted a san-mai blade of hard and soft tamahagane for a while now... but don't have the enormous amount of cash it would cost to have it made.

 

[Eamon Burke]

I guess what I meant was that the fantastic qualities exhibited by tamahagane blades are really showing off the skill of the person handling, heat treating, and otherwise making the blade. It's like trying to find paint with similar chemical composition to the paint Michelangelo used.

 

[Shimmer]

It may just be me, but those two might well be similar in properties when treated and handled correctly, but they do not look like a similar make up to me. Plus there's some wide tolerances in the Tamahagane there.

I challenge you to find a steel more closely related in make up to Tamahagane than 100WC10.

 

[mainaman]

my understanding is that they tested many types of steel from various makes and found this one to have properties most like what they were looking for. Both Iwasaki-san and his father are/were extremely well educated in metallurgy. I believe both studied at Tokyo University as well.

Actually, Sara and I just finished reading a book written by the elder Iwasaki-san on sharpening... to say that guy knew a lot is a complete understatement

which book the one for razors?

 

[JBroida]

which book the one for razors?

that one and some notes he sent along with the book

 

[Delbert Ealy]

Shimmer,
I don't know where you got the stats for your tamahagane, but the number that surprised me was the Si, for true tamahagane it should be much higher.
The biggest problem with comparing modern steels is the manganese content, manganese is added to keep the sulfur content low in the refining process and there is always some of it still remaining in the steel. You have a lot of numbers listed above, but most of them are trace and don't count for much, the Mn does make a huge difference. I think if you look at 1095 you will find it close in stats to the steel you listed

Just to let you know I have made tamahagane and am quite familiar with its properties.


1095
C .1.04 Mn .30 P .025 max S .050 max Si .15

 

[iceman01]

Actually, Sara and I just finished reading a book written by the elder Iwasaki-san on sharpening... to say that guy knew a lot is a complete understatement

Sounds like it needs to be translated to English.

 

[UglyJoe]

Delbert, I'm glad you've made tamahagane, and I'm glad more American's are playing around with it. I am not under the illusion - as I think some people are - that there is anything uber-special about tamahagane compared to a lot of modern steels, but I love that "from scratch" idea of a tamahagane blade. As I said in a previous post, traditionally in the huge tataras that are used to produce tamahagane in Japan the final steel ore has a wide range of composition, etc. Most of the American makers I have seen make it in a much smaller furnace, and I was wondering if you've had better luck in controlling the smelting process to get something a little more uniform in consistency?

 

[Delbert Ealy]

Joe,
I have had luck when I get anything at all, its not easy, although it is fun.

 

[JBroida]

Sounds like it needs to be translated to English.

we just finished our own translation... i'm editing it right now

 

[Shimmer]

Shimmer,
I don't know where you got the stats for your tamahagane, but the number that surprised me was the Si, for true tamahagane it should be much higher.
The biggest problem with comparing modern steels is the manganese content, manganese is added to keep the sulfur content low in the refining process and there is always some of it still remaining in the steel. You have a lot of numbers listed above, but most of them are trace and don't count for much, the Mn does make a huge difference. I think if you look at 1095 you will find it close in stats to the steel you listed

Just to let you know I have made tamahagane and am quite familiar with its properties.


1095
C .1.04 Mn .30 P .025 max S .050 max Si .15

These articles are a good starting point.

http://www.yamakawadojo.com/Tamahagane Production, Control of Slag.pdf

http://www.shibuiswords.com/tatsuoinoue.htm

I have a dozen other sources which all state the same general composition of this steel.

 

[SpikeC]

I guess what I meant was that the fantastic qualities exhibited by tamahagane blades are really showing off the skill of the person handling, heat treating, and otherwise making the blade. It's like trying to find paint with similar chemical composition to the paint Michelangelo used.

Excellent parallel! And as far as what most closely relates to tamahagane, which tamahagane?

 

[iceman01]

we just finished our own translation... i'm editing it right now

Excellent Jon, I'm really curious.

 

[mainaman]

that one and some notes he sent along with the book

yes I read it too pretty nice stuff . It helped me improve my strop a lot too.

 

[JBroida]

yes I read it too pretty nice stuff . It helped me improve my strop a lot too.

yeah... his talks about stropping and also the amount of time spent on each stone really make a lot of sense to me. Admittedly, i'm not a straight razor guy, so i'm always coming from the perspective of how i can make these things work for me with kitchen knives, so i probably read it a bit differently than most.

 

[Delbert Ealy]

Excellent parallel! And as far as what most closely relates to tamahagane, which tamahagane?

This is very true, I was using local materials(michigan), which may have an entirely different make-up than those listed(I am referring to the trace elements).

 

[mainaman]

Sounds like it needs to be translated to English.

it has been translated recently
http://japanshave.blogspot.com/2011/04/at-long-last-honing-razors-and.html
you can find the link for the D/L there.

 

[Larrin]

I agree with others that tamahagane is about the process and the tradition. In my opinion there is no reason to copy the composition.