# Tungsten blade core possible?



## augerpro (Mar 5, 2017)

Is it possible to use tungsten in blade manufacture? For example a Tungsten upper core, with an edge steel below of whatever, say Aogami Super, then clad in SS? Besides weight it appears strong besides.

I'm just curious if this would make it possible to make a laser that has the weight of a workhorse?


----------



## khashy (Mar 5, 2017)

Do you mean Tungsten Carbide?

[video]https://m.youtube.com/watch?v=Cytuz142KJs[/video]


----------



## Jovidah (Mar 5, 2017)

Just in theory... doesn't this mean you'll just end up with a heavy knife without food release? I don't really see the advantage there.


----------



## PolishAvenger (Mar 5, 2017)

It's possible to do, but I expect it would be quite costly. Then you'd have a blade with the weight of a workhorse, but the fragility of the laser edge geometry....doesn't sound like a match made in heaven.
-Mark


----------



## augerpro (Mar 5, 2017)

I'm not referring to Tungsten Carbide, that appears to be impossible to work with. I mean pure tungsten or possibly alloyed with iron, apparently they alloy quite well even at high amounts. And probably not at the cutting edge, so construction would be somewhat similar to a samurai sword, where different steels are using in different parts of the blade to accomplish different things.

So maybe laser is too extreme. But imagine a Tanaka, or better yet a Gengetsu or Ginrei, but with considerably more weight.


----------



## ThEoRy (Mar 5, 2017)

I thought that was exactly what makes Aogami Super well um Super. It's just blue steel with additional tungsten added. I know this isn't exactly what you are asking but it was my understanding that yes, tungsten is used in knife making.


----------



## Nemo (Mar 6, 2017)

Hap40 also has large amounts of tungsten in it (6.5% cf 2.5% in Aogami super). It's a pretty strong carbide former, so I imagine that most of it would be present as tungsten carbide.


----------



## LifeByA1000Cuts (Mar 6, 2017)

Might be hard to manufacture: Tungsten is extremely hard to melt or forge 

And tungsten-based alloys (which one would use as "metallic tungsten") aren't that hard: https://smp.es/en/tungsten 

It is the carbides you want in a knife...


----------



## augerpro (Mar 6, 2017)

ThEoRy said:


> I thought that was exactly what makes Aogami Super well um Super. It's just blue steel with additional tungsten added. I know this isn't exactly what you are asking but it was my understanding that yes, tungsten is used in knife making.



I'm looking at a lot more than a few percent. Enough to add real weight. And the edge would be a different metal, something typical. Basically a normal clad knife from outside appearances but with an interior tungsten portion.


----------



## Jovidah (Mar 6, 2017)

Just read the wikipedia page on Tungsten and you have your answer.


----------



## Bolek (Mar 6, 2017)

Ther is a tungsten carbid Zwillig rod : https://www.knivesandtools.fr/fr/pt/-zwilling-twin-1731-fusil-23-cm.htm
Havy tought quit fine and very hard. Comes with the zwilling-twin-1731 set (very special kanives).


----------



## augerpro (Mar 6, 2017)

Jovidah said:


> Just read the wikipedia page on Tungsten and you have your answer.



Well if I had the expertise to know what to look for in the wiki I wouldn't have posted this question! A google search shows it alloyed with iron at very high concentrations in papers from the 1880's and modern uses in high tech "super" alloys. To my untrained eye it certainly looks possible to combine with iron. Maybe even possible to simply clad with steel. 

FYI I am NOT talking about tungsten carbide.


----------



## jessf (Mar 6, 2017)

You'd have to sinter the shape or at least rough shape then grind the rest. iron cladding could be welded or braised to offer support. It would weigh a lot and likely require special sharpening methods. Tungsten ive seen doesnt really take acute angles that well without chipping. so while it might form a tough edge i doubt you'll be shaving tomatoes with it. Might be a good brute force bone cleaver though.


----------



## augerpro (Mar 6, 2017)

As I said, the tungsten is NOT the cutting edge. It is an interior portion that (could) extend up to the spine, with the cutting edge steel below it, both clad in stainless. Like a samurai sword. Or a normal clad knife but the core is not one piece but two: upper tungsten portion for weight, lower regular knife steel for the cutting edge.


----------



## WillC (Mar 6, 2017)

Sounds pretty loony tunes to me 

I can see the reasoning to want to increase weight, but it can all be done in the way you make the geometry of the blade, Thinner middle thicker spine. I mean you want the thickness in the blade still to a degree at the top of the lower bevel, thin knives aint the best cutters IMO you want some geometry and that requires leaving some thickness to give geometry, the weight is then inherent. Just my views. I can see the fun in the science though, Im not sure what is a reasonable level of Tungsten to be workable and at least somewhat stable in an Fe matrix.

If you really wanted an almost unworkable core steel, then you might use something like this.... at least those huge ugly carbides are going to be a little smaller and more evenly distributed by pm steel process................. Could be laminated with stainless/pure nickel. Never tried the steel so can't really comment, at least it may be some what maintainable in san mai. How the feeling of the cut.......I doubt its going to be buttery.........how usable you can get the steel will depend on heat treatment

https://www.crucible.com/eselector/prodbyapp/tooldie/cpmt15t.html

Study on heat treatment and carbide size and distribution in rex T15 so you can see what they got from the steel and compare - download link
https://www.google.co.uk/search?cli...O2hHov98weJhaOQBg#q=CPMT15+grain+micrograph&*


----------



## WillC (Mar 6, 2017)

Ah I get you a layer of Tungsten just to add weight either side of the core....... Ha ha sounds expensive.


----------



## rami_m (Mar 6, 2017)

@augerpro, your title is a bit of a misnomer and confused people. You are looking for a cladding or sub cladding? (I take that to mean a middle layer between the core and cladding) in tungsten. People take core to mean the cutting edge of the knife. 

What will said is right though makers add weight by getting a thicker spine which then add stiffening and other advantages. 

The question I would like to know is if there is a way to take a middleweight and add more weight without changing the geometry. 

There is also a second concern on how would that change the balance point of the knife? Would it make it blade heavy? Is that desirable? ( never used a kato so no idea) maybe you need to compensate using heavier handles?


----------



## jessf (Mar 6, 2017)

Pays to read the whole thread i guess, shame on me. He does mention it's the upper. Yeah, it's possible to do what you're asking.


----------



## augerpro (Mar 6, 2017)

I think I've pushed the geometry and balance of properties as far as they can go. I've had just about every knife you can imagine and right now have a Ginrei and Gengetsu that are the best so far, and I could probably live with either of them the rest of my life. But I just wonder what if they were 30g heavier, but the same geometry, how killer they would be?


----------



## rami_m (Mar 6, 2017)

augerpro said:


> I think I've pushed the geometry and balance of properties as far as they can go. I've had just about every knife you can imagine and right now have a Ginrei and Gengetsu that are the best so far, and I could probably live with either of them the rest of my life. But I just wonder what if they were 30g heavier, but the same geometry, how killer they would be?



Add a piece of putty to the knife?


----------



## Jovidah (Mar 6, 2017)

augerpro said:


> Well if I had the expertise to know what to look for in the wiki I wouldn't have posted this question! A google search shows it alloyed with iron at very high concentrations in papers from the 1880's and modern uses in high tech "super" alloys. To my untrained eye it certainly looks possible to combine with iron. Maybe even possible to simply clad with steel.
> 
> FYI I am NOT talking about tungsten carbide.



-Pure tungsten only melts at 3400 degrees celcius... so good luck forging that; it's a higher temperature than most forges can reach, especially smaller knife forges
-Due to the high forging temperatures, somehow creating a sandwich of tungsten and steel is not a trivial issue
-The way tungsten is usually worked with is not conducive to a proper heat treat for the other steels in your fancy knife sandwich

Is it entirely impossible? Probably not. If you have a few million bucks and an industrial forge around, it might be possible. But it'd be quite an expensive pet project... all without clearly identifiable benefit.


----------



## augerpro (Mar 7, 2017)

Thank you for the technical feedback!


----------



## rami_m (Mar 7, 2017)

Jovidah said:


> -Pure tungsten only melts at 3400 degrees celcius... so good luck forging that; it's a higher temperature than most forges can reach, especially smaller knife forges
> -Due to the high forging temperatures, somehow creating a sandwich of tungsten and steel is not a trivial issue
> -The way tungsten is usually worked with is not conducive to a proper heat treat for the other steels in your fancy knife sandwich
> 
> Is it entirely impossible? Probably not. If you have a few million bucks and an industrial forge around, it might be possible. But it'd be quite an expensive pet project... all without clearly identifiable benefit.



So how would you do it. How can you get heavier knives without changing geometry?


----------



## TimoNieminen (Mar 7, 2017)

If I wanted to add weight, and felt rich enough, I'd drill holes (or laser cut them) and plug them with gold. Maybe tungsten plugs would work, but gold will definitely work.


----------



## LifeByA1000Cuts (Mar 7, 2017)

Bismuth or lead would be a good start (not as heavy as tungsten* or gold) .... but you'd need to plug these holes with something on top ... creating another small problem: if you used gold on top, it would probably not stick very well if the process wasn't well controlled - gold tends to have a very brittle interface with lead....

*name's onomatopoetic in a way  "heavy stone" .... and heavy things tend to go "tung!" when dropped


----------



## Jovidah (Mar 8, 2017)

rami_m said:


> So how would you do it. How can you get heavier knives without changing geometry?



I honestly don't have a good answer to that - though I'm neither a knifemaker or a metallurgist. Usually I guess you increase weight by either increasing the height (changing the profile) or for example giving it a thicker spine (while still grinding away below to keep the original geometry). But by the time it's substantial enough to impact weight it'll most likely also impact geometry / cutting.

I guess you could go through the periodic table to see if there are any other metals worth considering to sandwich... but still I think it'd become a rather expensive project. A lot of the heavier metals are also the kind you don't want anywhere near food. It might also change the 'feel' of the blade ; the stiffness or how it reacts (vibrates) when hitting the cutting board. This would probably be a pretty long and difficult process of trial and error. My first step would be to toss out any metals that aren't food safe, so you don't have to laminate a different material on the top.


----------



## jessf (Mar 8, 2017)

Chinese cleaver will get you weight and thinness.


----------



## rami_m (Mar 8, 2017)

@augerpro

I like this sort of mental exercise; however take the below with a grain of salt. 

The way I see it you can try these options 

1. Get a lighter handle, this will drive the balance point of the knife forward and further away from your hand and make it seem heavier. 

2. Get a longer knife, extra length = extra steel/extra weight. Profile will be a little different but geometry should stay the same. 

3 add additional weight to the handle/tang. Will drive the balance point back but no changes to the blade and give additional heft 

4 material engineering: maybe a blade smith can do something for you?

5. Extra weight at the spine? This will change geometry but maybe depending on how much you may not notice the difference. Couple of mm thickness over the length of the knife especially at the spine can mean nothing performance wise, but it may depends what you use the knife for and how you use it.


----------

