New material

[Frosty]

There is a new material becoming available. It's only available in small jewelry size quantities right now but more will be coming online as demand allows.

I'm not connected to this other than being a friend of one of the inventors.

http://xpmcorporation.com/

Frosty

[ThomasPowers]

Interesting; they do a lot of explosive welding of dissimular metals out here with some of it going for art but most for industry.

[skunkriv]

Neat stuff Frosty. One of your friends from your early pyrotechnic days?

Bookmarked their site. May want to make a plate or bowl with this one of these days. Thanks for posting.

[Sam Salvati]

Cool Frosty, thanks for sharing!

[Frosty]

A friend from the Artmetal gang. I've known Jim Binnion for quite some time. Deb and I wear Mokume Gane wedding rings made by Jim.

Mokume Gane is done by diffusion welding, not fusion or explosive welding. In it's most basic form you clamp multiple layers of different metals together after very thoroughly cleaning them, then heat to sweating heat. Just below the lowest melting temp in the billet.

The iron or steel clamp expands less than almost anything you're going to put in the billet so the pressure goes extremely high.

At temp, under pressure the electrons in the different layers begin to exchange. Properly done the weld is as strong as the weakest metal in the billet.

Some metals are easy to do this with. For instance I've done copper and brass in my propane forge and once in a charcoal forge. Copper, brass and bronze are easy combinatins but don't have a lot of contrast. Copper and silver are another easy pair but silver and brass make silver solder and a puddle at a temp lower than the diffusion temp of either.

The methods Jim uses are a lot more sophisticated. Jim's been making mokume from combinations a lot of people consider on bordering the impossible. Gold and iron being one, titanium and zirconium another.

Jim and Steve have invented a process for making mokume in quantity and various shapes. It can be made from virtually any combination of metals.

It's pretty cool stuff. I can't wait to see my first set of Mokume Gane car rims, maybe bumpers.

Frosty

[matt87]

I'm interested in the mention of repeatable, predictable patterns. Wonder if we'll see Mokume Gane number plates soon? :D

[ThomasPowers]

Frosty explosion welding is a difussion weld not just a mechanical weld as was first thought.

Diffusion welding has several factors: cleaniness, deformation (pressure) and temperature.

Max any of them out and they stuff will try to weld.

"Solid Phase Welding of Metals", Tylecote gose into this in depth.

[whitebear]

is there a way to reprodue that at home?

son

[Frosty]

Frosty explosion welding is a difussion weld not just a mechanical weld as was first thought.

Diffusion welding has several factors: cleaniness, deformation (pressure) and temperature.

Max any of them out and they stuff will try to weld.

"Solid Phase Welding of Metals", Tylecote gose into this in depth.

Granted. However there is a difference in process that sort of excludes mokume gane from the explosive welding realm. The lack of an explosion. No?

If you come up with a version that does use explosive compression I don't know if you could call it mokume gane.

It's like calling pattern welding damascus. Sure both are generally made up of many welded layers but unless the metal originates from a batch of Wootz and the visible layers are made up of austentitic, martensitic, perlitic, graphitic, etc. steels it isn't properly "damascus."

Welding up billets of different alloy steels, folding, rewelding and manipulating produces similar results visually but the process was discovered/invented because western smiths couldn't reproduce true damascus.

Frosty

[Frosty]

is there a way to reprodue that at home?

son

It depends on what you mean by reproduce Son.

If you mean mokume gane in general the answer is a hearty yes. Many of the things Jim and Steve do take specialized equipment and materials but it's still doable in a home shop. Steve sells one of the best how to books on the subject.

If you mean reproduce their recently patented process of extrusion production, the answer is still probably yes. You'd have to figure out how they do it, buy or build the equipment and probably defend yourself in court. It's not really a home shop process though.

Frosty

[ThomasPowers]

Frosty; you said "Mokume Gane is done by diffusion welding, not fusion or explosive welding" so since explosive welding is a type of diffusion welding your statement thus contradicts itself.

What you need to do is to specify the *type* of diffusion welding used for Mokume Gane as it's not a vacuum weld either---another type of diffussion weld. Or galling, another type of diffusion weld.

And while I would like to exclude pattern welding from the term damascus actually both wootz and patternwelding have been generally know as damascus for over two centuries; so it's a bit hard to claim that one is excluded from the term. It's just a bad term if it can be used for quite different things; english is rather famed for it's ambiguity. I prefer to leave damascus alone and only refer to pattern welding and wootz myself. You may notice that german also uses the term "damascus" for pattern welded items as well.

But this is quibbling over terminology; far better to spend the time looking at the pretty stuff!

[matt87]

And while I would like to exclude pattern welding from the term damascus actually both wootz and patternwelding have been generally know as damascus for over two centuries; so it's a bit hard to claim that one is excluded from the term. It's just a bad term if it can be used for quite different things; english is rather famed for it's ambiguity. I prefer to leave damascus alone and only refer to pattern welding and wootz myself. You may notice that german also uses the term "damascus" for pattern welded items as well.

I prefer to use the term Damascus to the steel form the swords of Damascus -- that is likely Wootz steel (from certain periods at least...). I think that Damascene is a much better term for the more modern version. But I suppose it's like the magazine vs. clip debate; you can get by talking about putting a new clip in yoru Glock as most people will be able to figure out what you mean. When you talk about putting a clip into your Lee Enfield with a clip though, it can get a little more ambiguous! (Enfields have a detactchable magazine but the mag can be reloaded with clips from the top...)

But this is quibbling over terminology; far better to spend the time looking at the pretty stuff!

Exactly. :cool:

[Ice Czar]

take specialized equipment

to begin with an autoclave vacuum furnace?

Im not particularly interested in pattern welding or Mokume Gane (cost of materials), what Im very interested in is inlaying copper, brass and bronze into steel (at the surface) for differential patinas. While Ive experimented some, the physical hammering distorts the designs (which are representational rather than abstract patterns), and a traditional forgefurnace heated to the welding point provides too much oxidizing, traditional inlay is highly labor intensive ( I want to make lights, furniture and largish objet d' art)

As it happens I do have a 50's era autoclave (2'IDx4') and Welch duo-seal vacuum pump
but any great amount of heat would destroy the main seal unless I could rig up some sort of refractory replacement.

While I wouldn't want you to divulge any trade secrets, if I where able to come up with a a means to heat the chamber and maintain atmospheric integrity, with some sort of vise platten to sandwich the material, would I be on the right path?

I guess what Im asking is, what range of heat and pressure tradeoff would I be aiming for? So I could look for a refractory seal. Id probably be looking at an electrically heated platten since there is already an electrical pass through vacuum port for a light. (Conduction vs what its designed for with a heated jacket, its a medical autoclave)

Steve sells one of the best how to books on the subject.

Mokume Gane: A Comprehensive Study Book Part 1


a thought just occured to me
wouldnt it be cool to have a vise that incresed in its pressure when heated
one say driven by sealed gas pistons, containing CO2 that dramatically increase in pressure with heat
Green Chemistry Articles
bet you could even trial and error it provided you made sure the seal failed before the piston burst, seal failure might be its release mechanism, employing very small amounts of CO2 that are released in each cycle

[ThomasPowers]

Things get even messier with damascene as it also refers to a type of inlay often done on weapons; there are Indian swords that were welded up out of chevron shaped pieces of pattern welded and wootz steel and some of them might be decorated with damascene inlay as well. Well at least *everyone* would probably be willing to call such a weapon Damascus! (save for those who are location specific terminologists)

Not all crucible steel was wootz as Dr Feuerbach pointed out in her doctoral thesis "Crucible Steel in Central Asia". I'm am awaiting the publishing of her book on the topic with great interest!

[matt87]

Ah, good points there Thomas, my hat is off. There is of course the Huntsman process too; European from the 18th century I believe. May I please have the reference to that thesis?

[ThomasPowers]

Sure; I have it on a DVD at home. It will have to be next week as I leave for an anvil repair clinic today at 4 and won't be home or on-line till Monday.

Please remind me if I forget.

Thomas

[Frosty]

to begin with an autoclave vacuum furnace?

While I wouldn't want you to divulge any trade secrets, if I where able to come up with a a means to heat the chamber and maintain atmospheric integrity, with some sort of vise platten to sandwich the material, would I be on the right path?

I guess what Im asking is, what range of heat and pressure tradeoff would I be aiming for? So I could look for a refractory seal. Id probably be looking at an electrically heated platten since there is already an electrical pass through vacuum port for a light. (Conduction vs what its designed for with a heated jacket, its a medical autoclave)


Mokume Gane: A Comprehensive Study Book Part 1


a thought just occured to me
wouldnt it be cool to have a vise that incresed in its pressure when heated
one say driven by sealed gas pistons, containing CO2 that dramatically increase in pressure with heat
Green Chemistry Articles
bet you could even trial and error it provided you made sure the seal failed before the piston burst, seal failure might be its release mechanism, employing very small amounts of CO2 that are released in each cycle

I can't give up any trade secrets, I don't know any. What little I do know of thier new process involved extrusion presses.

Jim has been known to use a vacuum furnace but I believe he mostly seals the billets in foil with various oxy absorbing fillers. Charcoal would or could be one. I don't know the specifics.

A clamp that increases pressure as the temp rises is a steel clamp. Most combinations of metals used in mokume have greater expansion coeficients than steel so the billet expands more than the steel clamp. So, what you're thinking of is exactly what's happening without the danger of super heating a gas.

I have zero experience with vacuum furnaces and suggest researching the subject. Vacuums can be entirely too dangerous to mess with based on the opinions found on a public forum. I recommend getting professional advice.

I can't give you specifics for temps either, I eyeballed the couple billets I made and let them soak sweating heat. Sweating heat is where the metal begins to have a liquid looking sheen literally like it's beginning to sweat. Afterwards I found a couple tiny droplets squeezed from between layers near the clamp where it was hottest.

That billet was forgable across the layers so I evidently got it right. Good enough anyway.

Inlay is a whole different thing and something else I have no experience with. A little reading over the years is about it and certainly not enough to make my opinion useful.

Frosty