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[Uristocrat]

Super armor penetrating ballista bolts? APCFSB? 

Use pitchblende or cobaltite ammo in your catapults by putting a custom stone stockpile with only those really dense stones next to the catapult.  You can also use some other smeltable metal ores that are very dense (e.g. native gold, silver, or platinum), but I usually prefer to smelt them.

[Roraborialisforealis]

I think most know wolfram as tungsten (though the other name is why tungsten has W as its chemical symbol).  I'm not sure how well the alloys would go with DF's tech level.

But I'm interested to see someone else interested in material properties and I should probably have a talk with someone like you over how well the DF material attributes that exist can be adapted for wood, after having gathered all sorts of information in an effort to improve DF's simulation of wood's mechanical properties (see this and this to see what I'm talking about).

Wolfram is tungsten's original name because it was used commonly before the element tungsten was actually made official.

[Dr.Luuvalo]

Roraborialisforealis:
Agreed. One down side is that too many materials clutter up the ui, but that's really more of a failing of the ui.

Uristocrat:
Yeah that sort of slipped, I managed to get it right in the end though. I seem to subconsciously resist typing words of Swedish origin (like any decent Finn). The allous would probably go better with dwarven tech than the metal itself, as tungsten is really hard to work unless it's very pure. The being sorf when pure sort of the same thing as with iron and
 nickel ect. It's probably mostly due to the carbide impurities. On the other hand, tungsten alloy steel can be worked much like common steel.

Interesting threads. I'll try read them more closely when I can find the time and energy, and reply if I have something to add. I'm hardly qualified to talk about anisotropic materials like wood though.

Erkki:
Armor piercing capped fin stabilized bolt? Perhaps we should get uranium too! Pity that its pyrophoric effect probably won't work at typical crossbow bolt velocities.

[Roraborialisforealis]

Why not throw metals into teirs. Teir1: Non military grade. Teir2: Military grade Teir3: Precious metals. This would make the UI easier to navigate!

[Orakio]

Roraborialisforealis:
Agreed. One down side is that too many materials clutter up the ui, but that's really more of a failing of the ui.

Uristocrat:
Yeah that sort of slipped, I managed to get it right in the end though. I seem to subconsciously resist typing words of Swedish origin (like any decent Finn). The allous would probably go better with dwarven tech than the metal itself, as tungsten is really hard to work unless it's very pure. The being sorf when pure sort of the same thing as with iron and
 nickel ect. It's probably mostly due to the carbide impurities. On the other hand, tungsten alloy steel can be worked much like common steel.

Interesting threads. I'll try read them more closely when I can find the time and energy, and reply if I have something to add. I'm hardly qualified to talk about anisotropic materials like wood though.

Erkki:
Armor piercing capped fin stabilized bolt? Perhaps we should get uranium too! Pity that its pyrophoric effect probably won't work at typical crossbow bolt velocities.

The major issue with tungsten metallurgy is that it cannot be reasonably smelted, given the melting point of about 3400 C. It basically requires your choice of methane or hydrogen reduction, followed by powder forming and sintering. What it's hard to project back to that kind of time line is the furnaces required to do something like that. In theory you can get the rest of the process, from dissolving the ore in lye and back adding water until the oxide falls out, then you need the furnace, and you can grind iron/nickel down to powder and mix it with tungsten and beeswax to make forms, but then you need a furnace to sinter.

[Uristocrat]

Interesting threads. I'll try read them more closely when I can find the time and energy, and reply if I have something to add. I'm hardly qualified to talk about anisotropic materials like wood though.

You say that as if the rest of us have some special qualifications other than maybe a few basic physics classes   You're right though, that wood's strength is based on the grain of the wood and that DF's materials system was only seems suitable for things like metals.

[Cthulhu Inc]

to Cthulhu Inc:
Iridium is found on meteorites in trace amounts, though the amount is significant when compared to earths crust. You might have heard of the K–T boundary, a layer of iridium rich soil which is thought to be from the meteorite that caused the extinction event. Anyway, I think the concentration on iridium on meteorites is too low to affect the mechanical properties. You might be thinking of so called meteoric iron. It is famously tough and strong, and it is a natural alloy of iron and nickel. Perhaps iron meteorites could be added to the game.

That's what I meant; meteoric supermetal. Second only to mithril/candy.

[Dr.Luuvalo]

Roraborialisforealis:
That could work. Perhaps the categories could be defined in an init file, so that anyone could configure them as they will. One step forward would be that only materials that you actually have would show up in workshops ui etc.


Orakio:
Indeed, that is why I left W out of the original post. Tungsten mostly produced by reducing it with hydrogen because it is commercially viable. However, dwarves need not care about profit, they are powered more by insanity than greed. Dwarves could use some other reducing agent, for example carbon or perhaps sodium. Tungsten reduced with carbon would likely contain lots of carbides though, and sodiothermics sound like ‼fun‼. With some research more ways could be found. I don't know how high temperatures smelting W needs, but I'm pretty sure that it can be achieved at a temperature far below its melting point. For example iron can be reduced with in a bloomery at temperature of  ~1100ºC or below, with diminishing efficiency. More powerful reductant could likely work in even lover temperatures.

As you said, producing the oxide from ores is no problem, but actually using the smelted product is one. It is likely some sort of spongy mass too brittle to be forged, and has too high melting point to be melted into ignots. Somehow I can't imagine dorfs using powder metallurgy either. Tungsten can however form alloys with at least iron and nickel, so such alloys are the most likely utility dwarfs could have for W.


Uristocrat:
You never know , I think its better to over- rather than underestimate people. I've taken exactly two material science courses myself, and they aren't really helpful in this matter. They were more about choosing the right material for a certain task, rather than about the materials them selves.

(EDIT: fixed a typo)

[Roraborialisforealis]

to Cthulhu Inc:
Iridium is found on meteorites in trace amounts, though the amount is significant when compared to earths crust. You might have heard of the K–T boundary, a layer of iridium rich soil which is thought to be from the meteorite that caused the extinction event. Anyway, I think the concentration on iridium on meteorites is too low to affect the mechanical properties. You might be thinking of so called meteoric iron. It is famously tough and strong, and it is a natural alloy of iron and nickel. Perhaps iron meteorites could be added to the game.

That's what I meant; meteoric supermetal. Second only to mithril/candy.

Ive always been curious on how you get candy.

[Roraborialisforealis]

Wait. IS candy a codeword for that secret metal?

[squishynoob]

How about Manganese?

There are already manganese minerals in game (Pyrolusite, MnO₂). It has uses in steel making.

[nanomage]

I doubt it can be smelted, and smelting seems to be the prerequisite for dwarves to have access to metal.

EDIT: using manganese ores to enhance propertis of steel without directly reducing them to the elemental manganese would make sense though

[LostCosmonaut]

While looking through one of my engineering textbooks, I found some interesting information. These aren't new metals, per se, but some alloys and their properties that could potentially be useful. Also, some existing materials are provided for comparison.

Structural Steel
      Modulus of Elasticity: 200 GPa
      Modulus of Rigidity: 77.2 GPa
Gray Cast Iron
      Modulus of Elasticity: 69 GPa
      Modulus of Rigidity: 28 GPa
Annealed Copper
      Modulus of Elasticity: 120 GPa
      Modulus of Rigidity: 44 GPa
Yellow Brass (65% Cu, 35% Zn), Cold Rolled
      Modulus of Elasticity: 410 GPa
      Modulus of Rigidity: 250 GPa
Tin Bronze (88% Cu, 8% Sn, 4% Zn)
      Modulus of Elasticity:95 GPa
Monel Alloy (Ni-Cu)
      Modulus of Elasticity: 180 GPa
Interestingly, this material had the highest yield strengths of anything listed in the table (including multiple steel allloys). I think Modulus of elasticity and shear would be more important though, in order to prevent deformation.
Cupronickel (90% Cu, 10% Ni)
      Modulus of Elasticity: 140 GPa
      Modulus of Rigidity: 52 GPa


Not sure how well any of these would fit in with the setting of DF, but it's just something I found and thought might be useful.

 
     


       

[Dr.Luuvalo]

Roraborialisforealis:
Yup, cotton candy, served by clowns as one might expect.

Squishynoob & nanomage:
I thought about manganese when writing the op, and became to conclusion that dwarves could probably not smelt it. It was before I thought about more exotic reductions, an also I didn't consider smelting it directly into alloys. So yeah, it probably could be done. Manganese could be used to make wonderful copper and iron alloys.

LostCosmonaut:
Good work, it is often hard to find elastic moduli for alloys. I take that the Modulus of elasticity refers specifically to Young's modulus, and MoR is shear modulus. I'm surprised to see that cast iron has so much lower stiffness than steel or pure iron. Cast iron could certainly be used by dwarves. If blast furnace type method of producing iron is ever implemented, cast iron could become a cheap material for furniture etc. Yellow brass has very high values, so high that it makes me wonder if they're correct. Cold rolling should not increase the materials stiffness.

It would be nice is you could provide us with ultimate tensile strength and tensile yield strength values for those materials. It would be easier to comparison with values from other sources easier.

Engineering books tend to have their material values in a bit shoddy way, at least in the books I have. They list values from different sources, and rarely mention how the tested material was formed. Heat treatment, work hardening etc can have a huge effect, especially on yield strength. Then again manufacturers often forget stuff like elastic moduli and Poisson's ratio, which are interesting from mechanics point of view.

Stiffness itself is actually not very important value when comparing performance of metals for weapons and armor, they only prevent deformation until the yield strength is reached. Pretty much all otherwise suitable metals are also stiff enough. For example if we had a material with identical yield strength as DF steel, but one third of its stiffness (~70GPa), it would deform three times as much until yield strength is reached. This means that at yield point it would still deform less than 1%, which is not enough to affect penetration significantly. If you'd hit so hard that the weapons would exceed their elastic limits, both would deform at same rate. Less stiff weapon would also absorb three times as much elastic energy at yield point, but I imagine these energies to be small anyway.

[Roraborialisforealis]

Roraborialisforealis:
Yup, cotton candy, served by clowns as one might expect.

Squishynoob & nanomage:
I thought about manganese when writing the op, and became to conclusion that dwarves could probably not smelt it. It was before I thought about more exotic reductions, an also I didn't consider smelting it directly into alloys. So yeah, it probably could be done. Manganese could be used to make wonderful copper and iron alloys.

LostCosmonaut:
Good work, it is often hard to find elastic moduli for alloys. I take that the Modulus of elasticity refers specifically to Young's modulus, and MoR is shear modulus. I'm surprised to see that cast iron has so much lower stiffness than steel or pure iron. Cast iron could certainly be used by dwarves. If blast furnace type method of producing iron is ever implemented, cast iron could become a cheap material for furniture etc. Yellow brass has very high values, so high that it makes me wonder if they're correct. Cold rolling should not increase the materials stiffness.

It would be nice is you could provide us with ultimate tensile strength and tensile yield strength values for those materials. It would be easier to comparison with values from other sources easier.

Engineering books tend to have their material values in a bit shoddy way, at least in the books I have. They list values from different sources, and rarely mention how the tested material was formed. Heat treatment, work hardening etc can have a huge effect, especially on yield strength. Then again manufacturers often forget stuff like elastic moduli and Poisson's ratio, which are interesting from mechanics point of view.

Stiffness itself is actually not very important value when comparing performance of metals for weapons and armor, they only prevent deformation until the yield strength is reached. Pretty much all otherwise suitable metals are also stiff enough. For example if we had a material with identical yield strength as DF steel, but one third of its stiffness (~70GPa), it would deform three times as much until yield strength is reached. This means that at yield point it would still deform less than 1%, which is not enough to affect penetration significantly. If you'd hit so hard that the weapons would exceed their elastic limits, both would deform at same rate. Less stiff weapon would also absorb three times as much elastic energy at yield point, but I imagine these energies to be small anyway.

Alright. Thanks. I did manage all the HFS's before coming here. (One time I held out against the circus for a day! That's how long it took for the year to pass.(See my military building thread to see how the hell (lol.) I can last a year against (Firebreathing, Silver, poisonous exploding.) kitten clowns.))\
To be honest, I feel that if the dwarfs make a metal out of at least 50% weapon grade metal, It should be valid as a weapon material, but to keep the UI clean, only the basic "Traditional" weapon materials will appear without a sample of said metals present.
PERHAPS being able to make what metals a civ uses a cultural thing too (As well as how they use them.)