damascus steel

[sudsy909]

ok i know i might be starting a long discussion but hopefully i can learn alot from this post what is up with damascus steel are knives like kasumi and ryusen and all of these other makers really made out of damascus steel are there any benefits to the process of damascus or is it just asthetics where do the high prices come from is it the type of steel the amount of work what does it all boil down to? any info would greatly be appreciated ryan p.s. does any body have any info on bob kramer's knives pretty expensive does anybody have any comments on them thanks alot

[Fred]

The construction is warikomi - thin hard stainless steel in the core of a sandwich and "damascus" on the exterior. I prefer to call it forge welded stainless since it really isn't damascus in the classic sense.

The purpose of the forge welded steel is purely cosmetic.

These knives perform quite well. The hard core is VG-10 hardened to around RC60 so they work as nicely as they look. I'm sorry I have no experience with the custom knives you mention. I can tell you that every custom kitchen knife I've encountered has been a disappointment except, of course, for the Japanese bladesmiths. That's not an indictment of Cramer's knives since I have no experience with them. It is just a comment.

[Oded]

The original reasons for Damascus steel was the inability to control the amount of Carbon in the steel. The blacksmith of old could produce steel with either too much or too little Carbon. By alternatively layering the two types they were able to overcome the disadvantages of either and ‘average out’ the carbon content (partly because carbon would precipitate from the high carbon to the low carbon steel).

Later, sword and knife makers, Japanese smiths included, have adapted this construction. The process of pounding, folding and pounding again was used in order to improve ductility toughness and resilience of the soft lamination.


When it comes to modern, machine made knives I tend to agree that the Damascus is for cosmetic reason only.

Watanabe however claims that his Kintaro Ame knives (which is after all a Damascus steel) are indeed tougher then other. I have an email from him explaining why, probably on my home PC. I will try to find it when I am back home.

Now, before I get myself into one of our usual ‘ heated debates’:
1. I do not know whether this is true or not.
2. I cannot explain the physics of it (but this is not to say that such explanation does not exist).
3. Even if we assume that Watanabe’s claims are the absolute truth, I cannot say whether anyone of us can feel a practical difference.

After, how many of us have actually broken their blades…? Seeing Morimoto pounding a nail with his knife I dare say these knives are tougher then I would have thought, with or without the Damascus …

[Fred]

I agree with Watanabe. The idea is to mix soft and hard steel in the forge welding. The hard steel contributes to edge retention and the soft steel contributes to toughness. If they were melted and mixed together you would have neither. But forge welding them together does have this effect.

In a warikomi blade, however, the cutting is done by the core steel. The damascus on the exterior just looks nice.

[Sid Post]

A further distinction on the Damascus knives from someone like an ABS (American Bladesmith Society) MS (Master Smith) is that the whole blade is Damascus all the way through, not just the sides as seen in common Japanese blades.

In Japanese kitchen knives, "Ink Pattern" is often used to describe a wire Damascus process versus the traditional folded steel process as I understand it. This is just a surface treatment for cosmetics only.

[Oded]

Watanabe's remark refers to the advantage of multi layered (i.e. Damascus) exterior VS single layer exterior.
He does seem to believe that 16 layers of alternating Wrought iron and low carbon steel has a structural advantage over a single layer of either...