Composition of Japanese White & Blue Steel?

rdangerer

rdangerer

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May 26, 2000
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I'm looking to buy some nice chisels (woodworking)... so doing some research before I invest.

Question... do any of you have information on the composition of the Japanese "white" and "blue" steels that are used in kitchen knife and chisel making? Any web links you can provide?

Both are carbon steels, obviously high carbon since hardnesses are often Rockwell C 63-65 (which frankly sounds like it could be a bit hard / brittle for something subject to impacts, like a chisel).

I think Hitachi makes one or both of these, and of course others may also.

Info appreciated... thanks.
 
I could be way off on this, but in gun world we use the exact same phrasing for this:

"In the white" is unfinished steel
and blue of course is blued steel(which is an oxidizing process to give a blue to black finish, if you don't know). Least, think it's oxidizing. :)

Anyways, I could be far off, but tahts' just my first thought when you said white and blue steel.
 
White steels are simple, basicly iron and carbon, and little else steel.
Blue steel tends to be tungsten/ chromium steels, they cause the steel to have a blue or bluish gray color.
 
A good place to buy Japanese chisels is from japanwoodworker.com, which has a store in the San Francisco bay area. Check them out.

As for the meaning of the colors regarding the different types of steel, both are made by Hitachi, and, believe it or not, the white steel comes from the manufacturer with a white paper label, and the blue steel comes with a blue label. Some people refer to the blue steel as "blue paper steel", and the white as "white paper steel". Japanese call the white stuff shirogame hagane, and the blue steel aogami hagane.

Both are high carbon steels, with about 1.0 to 1.2% carbon, with 0.1 to 0.2% silica and 0.2 to 0.3% manganese. The blue steel also contains 0.2 to 0.5% chromium and 1.0 to1.5% tungsten.

The more complex blue steel yields a longer-lasting edge, is more expensive, and also requires more skill to manufacture.

I have a number of blue steel dovetail chisels. They take a wickedly sharp edge, but are much more brittle than European chisels and easily chip in harder, denser woods unless used very carefully. The Japanese tend to work in softer woods than we Westerners do, and their hard, brittle (approx. rc 63 or 64) tools hold up fine for them.

Hope this helps!
 
About Hitachi "white" and "blue" steels:

The actual Japanese words are Kigami (translated as white steel) and Aogami (translated as blue steel). The literal translations are approximatly "blue paper" and "silver paper".

These are two examples of the several traditional cutlery and tool steels made by the Hitachi's Yatsugi plant.

Both are high purity high carbon steels that are typically hardened to very high HRC (61+). They are used in traditional knives, swords, chisels, scissors, and other cutting tools.

Hitachi uses modern manufacturing processes, but these steels are made to equal the best traditional handmade Japanese charcoal steels.

The #1 A grade of white steel is (weight percent, balance Fe):

C: 1.3-1.4
Si: 0.10
Mn: 0.20
P: 0.025
S: 0.004

The #1 A grade of blue steel is the same with additions of:

Cr: 0.30%
W: 1.5%

The white steel has a more consistent microstructure and is considered in Japan to provide the ultimate cutting edge. The blue steel are considered to provide a slightly more durable cutting edge for wood chisels and heavy-usage kitchen cutlery.

Both white steel and blue steel are sold in at several grades which vary in carbon content: #1, #2, #3, etc. Each of these grades is further divided into "A" and "B".

For example here are a few carbon levels (weight percent):

#1 A - 1.3 to 1.4
#1 B - 1.2 to 1.3
#2 A - 1.1 to 1.2
#2 B - 1.0 to 1.1
#3 A - 0.9 to 1.0
#3 B - 0.8 to 0.9

These steels are mostly used in laminated knives and tools: a thin layer of white or blue steel is forge welded to one or more layers of soft steel (traditionally wrought iron, now usually mild steel or in non-traditional pieces soft stainless). This provides a very hard, brittle, sharp cutting edge supported by the softer metal.
 
Do a search. Somewhere, somebody quoted Murray Carter about the compositions of these steels. I am almost positive that the Blue steel contains a decent amount of Vanadium as well.
 
nhamilto40,
Seeing as you know so much about these steels... do you know where to get them.
I would really love some of that white steel #3B, but theres nothing like that here in the US.

Thanks for the info, by the way.

Joe Renner
 
Good stuff guys... many thanks for the detailed compositional posts. And the confirmation that for me, the Rc63-65 (and expensive!) Japanese chisels are not for me, at least not for a first full set for general use.

So it appears the Hitachi White grade 3A is very similar to 1095.

And the Hitachi Blue steels are like slightly enhanced W1 ... about 2x to 3X as much Tungsten, but nothing close to the true M series high speed steels in terms of Tungsten. That kinda knocks the luster/hype off the whole White/Blue Japanese steels thing... which is appropriate.

Thanks again.
 
Joe Renner:

I recommend that you try commercial W108 or W109 as a substitute for Hitachi white #3B. Should be identical for all practical purposes.

Code: 
Compositions (weight %)

      W109          Hitachi #3B
C     0.9 nom.      0.8-0.9
Mn    0.10-0.40     0.20 nom.
Si    0.10-0.40     0.10 nom.
Cr    0.15 max.     ...
Ni    0.20 max.     ...
Mo    0.10 max.     ...
W     0.15 max.     ...
V     0.10 max.     ...
P     0.025 max.    0.025 max.
S     0.025 max.    0.004 max.

Good Luck.
 
Actually, the steels would be suprizingly different, for what I do.
Also I havent seen any W1 that "plain" for a long while. Everyone Ive talked to switched theirs to 1095 to make things easier. They all say there might be a place or 2 out there still making it, but it eludes me.
I also found out that hitachi does not export the more premium steels, as the melts are very small and costly, to begin with.
To get the kinda steel I want Ill probably have to get a producer to make a small amount(large amount to me, think tons) or smelt it myself, which sounds far fetched to some but really isnt.

Thanks,

Joe Renner
 
I wandered into this thread and thought it might be a good place to ask about Cowry-X from Daido Steel. I wrote up a fair amount of information about this steel at:

Cowry-X overview
 
I think its risky choice of daido's steel.
Daido havent made good cutlery steel of melting method still now.And also they have few customer of cutlery steel in Japan.
But im a hitachi-metallurgist.

Good luck
 
JapanSteel,

How about ZDP-189 from Hitachi? I have had difficulty finding information about it in english.

Gabe
 
So i dislike marchants.
Marchants say only things about market sutatus.
Marchants let steel maker make new alloy by almost only
themselves opinion.And they dont have much scientific
opinion.So non-rational alloy of blade is increaseing.
Cowry and ZDP-189 might be made by such a way.
At least,i didnt design such alloys.
It seems to be important to exist reason of both market status and scientific opinion.Many kinds of subjects that is driven
by market optimization completelly exist.
 
I have a Murray Carter catalog and he list a "White #1" and "Blue Super" steel, along with their compostions. They have a bit more Carbon and less Sulfur than indicated in the thread by nhamilto40. Maybe they are different types of the white and blue steels.

Also Danbo - there is 0.36 V in the Blue Super steel.

I am no steel expert, just a guy with Murray's catalog.
 
Japansteel,
Do you know Ichiro Kishigami? He is an senior engineer at Hitachi metals. Just curious.

Also, does Hitachi make any carbon steels using electric arc furnaces? If so, any high carbon?

Jason
 
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