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View Full Version : Mithril = Aluminium. Discuss.



EccentricCircle
2012-02-18, 06:52 AM
So I was thinking about Airships, as I usually do. And pondering how the cultures of my D&D world could get around the difficulties of building early 20th century style flying machines with the technology of a fantasy world. Sure you can just say "oh its magic." But wheres the fun in that?

It occured to me that as a light, strong metal Mithril would be the best material to build an airships frame. Although the vast cost would be prohibitive.

Of course this was also true of Aluminium, (from which airships are actually built). Up until the late 1800's aluminium was an extreamly rare and precious metal, more expensive than gold. Nowerdays we can manufacture it easily but this wasn't always the case.

So my airship building problem is solved, Alchemists have discovered a way to create mithril in large quantities (which will certianly have interesting effects on the economy of my world...).

Anyway this has led me to the interesting conclusion that Mithril was Aluminium all along. but no one has ever noticed before.

Discuss.

Acanous
2012-02-18, 06:56 AM
I find it hard to believe that aluminum armor would confer the same AC bonus as steel or Adamantium.

As for airship design, sure!~

Spiryt
2012-02-18, 07:04 AM
Mixing up actual metallurgy, materials etc. with D&D can bring the headache real quick.

Anyway, I guess comparison could work, but mithril is generally, traditionally treated as something more "miraculous", like it's strong, resistant to most forces, hard etc. without any actual flaws.

Some reading (http://www.g2mil.com/aluminum.htm)

Waddacku
2012-02-18, 07:11 AM
One breaks easily, the other doesn't break easily. I do not think it's a good comparison.

hamishspence
2012-02-18, 07:11 AM
I occasionally wondered if it might be titanium- which also has the durability + lightness combination.

But, as mentioned, it seems more "magic metal" than anything else.

Spacewolf
2012-02-18, 07:31 AM
Well Al isnt exactly easy to extract as i still think it uses Electrolosis like Ti, hell if you could come up with a better way you would be a millionare very quickly.

As for the question in this situation they are probably similar but why dont you just make Al as it reduces the problem of getting basically unlimited super metal that can do everything better than just about anything else which would therefore breaking the economy of the setting

Belril Duskwalk
2012-02-18, 07:58 AM
Wood is a reasonable, cheap and proven material for building early flying machines. If you want to have your planes made of metal, I would suggest having your alchemist discover a way to produce actual aluminum, rather than breaking the economy and make mithril the global standard material for mundane gear. If you don't want to call it aluminum you could have your alchemist call it 'alchemical mithril' or something. Have it mimic most of the properties of mithril except for the fact that it is brittle, thus liable to break when struck with a sword, making it bad material for building armor and weapons.

STsinderman
2012-02-18, 08:23 AM
Totally second what Belril just said, the direct comparison cause far too many mechanic problems. The best option would simply be to have the alchemist discover a light but brittle metal, in that way you have your need filled for the ship, yet will not cause any world shattering changes. One example of which being, if it can be created in abundance this could very well trigger an industrial revolution within the cities while bankrupting many mining towns who relied upon the income of the now useless iron.

Crossblade
2012-02-18, 10:40 AM
I find it hard to believe that aluminum armor would confer the same AC bonus as steel or Adamantium.

Adamantium is also a fictional metal, for the record.

prufock
2012-02-18, 11:22 AM
Mithril is harder than iron (hardness 15 vs iron's 10). Aluminum is much less dense than iron (2.7 g*cm^-3 vs iron's 7.9). Armor made of aluminum would be... not so good.

MesiDoomstalker
2012-02-18, 12:02 PM
Please excuse me if my lack of knowledge of airplane (or airship for that matter) design but wouldn't making an airship out of a lightweight but relativly weak (compared to iron or mithril) be a bad idea if the ship is ever expected to see combat? In modern world, I doubt there is many materials that could be feasibly used in an aircraft that could stand up to bullets and missiles and such, but in a fantasy world, an airship will have to take massive weights and bolts flying at them as well as a myriad of magical explosions and such. A weaker metal like aluminum would quickly fail corrupting the hull and the structural integrety if the right spots were hit right. Or am I totally off based with this? Or were you planning on making the frame of Aluminum and the hull as something tougher?

SpaceBadger
2012-02-18, 12:28 PM
Please excuse me if my lack of knowledge of airplane (or airship for that matter) design but wouldn't making an airship out of a lightweight but relativly weak (compared to iron or mithril) be a bad idea if the ship is ever expected to see combat? In modern world, I doubt there is many materials that could be feasibly used in an aircraft that could stand up to bullets and missiles and such, but in a fantasy world, an airship will have to take massive weights and bolts flying at them as well as a myriad of magical explosions and such. A weaker metal like aluminum would quickly fail corrupting the hull and the structural integrety if the right spots were hit right. Or am I totally off based with this? Or were you planning on making the frame of Aluminum and the hull as something tougher?

Airships are fragile and should stay out of combat. If you want to make a tough airship that can take damage and stay in the air, you're going to have to do that with magic, not technology.

Zeta Kai
2012-02-18, 12:56 PM
According to The Science of Middle-Earth by Henry Gee (a great book, BTW), mithril may be a rare-earth compound known as yttrium silver. It has most of the properties that mithril was purported to have, & it is so rare that it doesn't exist on Earth (anymore?) in any usable quantity. Another theory is that it was a romanticized version of titanium, like how industrialists in the early 20th century claimed over & over that concrete was fireproof, even though it isn't.

EccentricCircle
2012-02-18, 02:38 PM
Interesting comments. I like the idea of Alluminium being a distinct "Alchemical Mithril" that is a great idea and should fit quite well with the setting.
I agree that Mithril is supposed to be stronger than steel, while Aluminium isn't so its not an exact comparison.

As for use as an armour material an Airship is not going to be especially well armoured, and there's probably not that much need for it to be. Adventurers might go around getting into trouble, but the majority of merchants and traders would be staying out of harms way most of the time. For the record I'm thinking of an aluminium frame with canvas gasbags and skin, with light wood hull in the crew compartments. Rather than a metal ship made entirely of armour plating (be it Mithril, Titanium, or Aluminium).
I'll have to check out the Science of Middle earth book, the concept sounds right up my street.

Hiro Protagonest
2012-02-18, 02:41 PM
Mithral is TITANIUM. Titanium is as strong as steel but 45% lighter, roughly on par with mithral.

Mando Knight
2012-02-18, 03:06 PM
Have it mimic most of the properties of mithril except for the fact that it is brittle, thus liable to break when struck with a sword, making it bad material for building armor and weapons.
Aluminum is not particularly brittle. It's softer (ergo less brittle) than iron, actually, though it lacks iron's odd qualities in fatigue. Until you get specific heat-treated alloys, in which case it does get relatively brittle.

Mithril is harder than iron (hardness 15 vs iron's 10). Aluminum is much less dense than iron (2.7 g*cm^-3 vs iron's 7.9). Armor made of aluminum would be... not so good.
Density is mostly about weight. You're looking for stiffness and hardness, and in both cases aluminum is inferior to steel, even alloyed.

Please excuse me if my lack of knowledge of airplane (or airship for that matter) design but wouldn't making an airship out of a lightweight but relativly weak (compared to iron or mithril) be a bad idea if the ship is ever expected to see combat? In modern world, I doubt there is many materials that could be feasibly used in an aircraft that could stand up to bullets and missiles and such, but in a fantasy world, an airship will have to take massive weights and bolts flying at them as well as a myriad of magical explosions and such. A weaker metal like aluminum would quickly fail corrupting the hull and the structural integrety if the right spots were hit right. Or am I totally off based with this? Or were you planning on making the frame of Aluminum and the hull as something tougher?
The frame is part of the hull. Also, aluminum alloys are sufficiently strong. Not as good as titanium alloys, but their weight-specific strength makes them better for aircraft construction than steel, though frames have to be a bit bulkier to compensate for the lost stiffness.

All in all, Mithral > Aluminum. By far. It's closer to a highly-polished magic titanium alloy or something.

Spiryt
2012-02-18, 03:16 PM
"Steel" can mean so many damn things, even without significant other compounds than iron and carbon, that it's pretty impossible to talk about it without specifying what steel we have in mind.

Incredibly varied stuff, as far as tensile, flexural strength, hardness, brittleness, ductility will be the result.

Stuff like aluminum and titanium also can differ in properties quite a lot, depending on alloy, object shaping method and so on.

My 'metallurgy' learning ended in 8th grade, lol, but I know that much. :smallwink:

kieza
2012-02-18, 03:45 PM
I've done this with my setting. Raw mithril/aluminum is lightweight but not particularly strong; it needs to be alloyed in order to get the protective qualities. (The alloy in question is 7075 aluminum alloy (http://en.wikipedia.org/wiki/7075_aluminium_alloy): strength comparable to steel, about 1/3 the weight.) Raw mithril is still fairly pricy, but not nearly as expensive as the alloyed stuff. It gets used a lot in dirigible frames, which are the pinnacle of aeronautic technology at this point.

Similarly, adamantine/tungsten is hard, but brittle and extremely dense. If alloyed into tungsten carbide (very hard, stronger than steel, about twice as heavy, and it has the darker sheen that I associate with adamantine), it becomes the highly useful adamantine we all know, but that process was lost ages ago. The only modern source of adamantine is ancient artifacts; they can be used as-is, or, if you know what you're doing, the metal can be reworked into something new.

Knaight
2012-02-18, 03:55 PM
Similarly, adamantine/tungsten is hard, but brittle and extremely dense. If alloyed into tungsten carbide (very hard, stronger than steel, about twice as heavy, and it has the darker sheen that I associate with adamantine), it becomes the highly useful adamantine we all know, but that process was lost ages ago. The only modern source of adamantine is ancient artifacts; they can be used as-is, or, if you know what you're doing, the metal can be reworked into something new.
Tungsten Carbide is far too inflexible to be effective in most weapons - though arrowheads should be entirely functional. Sure, it works in modern stuff, but a sword? Sadly, no. Plus, the whole "several times heavier" detail is rather inconvenient.

Spiryt
2012-02-18, 04:06 PM
Tungsten Carbide is far too inflexible to be effective in most weapons - though arrowheads should be entirely functional. Sure, it works in modern stuff, but a sword? Sadly, no. Plus, the whole "several times heavier" detail is rather inconvenient.

It depends on particular weapon and it's shape, I guess, I would imagine that stiffness wouldn't be too much problem in something like warhammer - and big density could probably be pretty beneficial too.

Mando Knight
2012-02-18, 04:13 PM
I've done this with my setting. Raw mithril/aluminum is lightweight but not particularly strong; it needs to be alloyed in order to get the protective qualities. (The alloy in question is 7075 aluminum alloy (http://en.wikipedia.org/wiki/7075_aluminium_alloy): strength comparable to steel, about 1/3 the weight.) Raw mithril is still fairly pricy, but not nearly as expensive as the alloyed stuff. It gets used a lot in dirigible frames, which are the pinnacle of aeronautic technology at this point.

7075-T6 aluminum (T6 refers to the heat treatment, which is needed for using it in most aircraft structural issues) has its drawbacks, which do not correlate with Mithral's stats in D&D 3.5 (or anywhere, really).

1.) It's still not as stiff as structural steels. By far.
2.) That specific strength? It's per unit mass, which means that for a less dense material like aluminum, the same mass will be bulkier, which is bad for armor plating.
3.) Heat-treated, alloyed aluminum is no longer as magically impervious to corrosion as people believe it to be.
4.) It has worse fracture toughness qualities than many steels.

We use aluminum in airframes because it provides specific advantages (specific strength, mostly) over steel. Mithral, however, is given as a super-metal that is simply better than steel, something that aluminum is most definitely not. I would go with Ti 6-4 instead as a mithral equivalent.

Gavinfoxx
2012-02-18, 04:28 PM
Sorry, but no. Mithral is STRONGER than steel.

I'd call it something like this:

D&D Iron or Steel (same material in D&D) = Real life Iron or low quality Steel.

D&D Greensteel = Our best, highest quality, strongest steels

D&D Densewood = Teak, some of our heaviest woods

D&D Mithral = Carbon Nanotubes, or other near future super materials

Anyway, the point of this is that, in general, D&D material science has several super materials that are BETTER than real life materials, even stuff that we are likely to get in the near future... Mithral, Adamantine, Glassteel, Obdurium, Duskwood, etc. etc.

Knaight
2012-02-18, 04:32 PM
It depends on particular weapon and it's shape, I guess, I would imagine that stiffness wouldn't be too much problem in something like warhammer - and big density could probably be pretty beneficial too.

I could see it working for maces, warhammers, etc. Axes are a possibility as well - but most everything else with a blade is not going to be functional.

Mando Knight
2012-02-18, 04:36 PM
D&D Mithral = Carbon Nanotubes, or other near future super materials

Carbon nanotubes are currently mostly too buzzword-y. They've got fantastic properties, sure, but they're weaker in compression and don't scale as well... and have poor thermal/reactive properties in atmosphere.

Spiryt
2012-02-18, 04:43 PM
I could see it working for maces, warhammers, etc. Axes are a possibility as well - but most everything else with a blade is not going to be functional.

Perhaps inflexibility could cause some problematic vibrations and general shock in percussion weapons as well?

Although wooden haft would probably be sufficient to damp them a lot, I guess....

fusilier
2012-02-18, 07:05 PM
Wood is a reasonable, cheap and proven material for building early flying machines. If you want to have your planes made of metal, I would suggest having your alchemist discover a way to produce actual aluminum, rather than breaking the economy and make mithril the global standard material for mundane gear. If you don't want to call it aluminum you could have your alchemist call it 'alchemical mithril' or something. Have it mimic most of the properties of mithril except for the fact that it is brittle, thus liable to break when struck with a sword, making it bad material for building armor and weapons.

Schutte-Lanz airships built in the pre-WW1 period, were superior to early Zeppelins and had a wood structure. To my knowledge they were the only other successful rigid airship prior to WW1. The British built some rigids during the war, that used wood as well.

Likewise, non-rigid airships were built without the use of aluminum.

Airships were used in combat, and I don't quite understand comments about them being too "fragile" for combat -- assuming you not try to ram other airships, or castles. :-) Traditionally they were used for scouting and bombing, and during WW2, blimps were excellent at detecting and attacking submarines. They were vulnerable to anti-aircraft fire, and the use hydrogen meant that they were susceptible to incendiary ammunition. Helium gives them much more protection, but only the US had sufficient helium reserves to use, and it had already abandoned big rigid airships by WW2.

A rigid airship, with many gasbags will be able to sustain damage (as long as it's not fire when hydrogen is used), while providing many points for defense. If mithril is light enough, it may be used to armor key locations, but armoring the entire envelope would be probably be too much. But wouldn't be necessary as a structural component.

As others have already pointed out aluminum doesn't make a good armor, but mithril does.

Xuc Xac
2012-02-18, 10:01 PM
Mithral is TITANIUM. Titanium is as strong as steel but 45% lighter, roughly on par with mithral.

Titanium is as strong as the lowest quality steel. It's also much softer than hardened steel. To get the same protection, you would need much more material. A chainmail hauberk is like a sweater made of metal, but a titanium hauberk would be like wearing a thick parka made of metal. In other words, it's great armor for people who want to waddle around like the Stay Puft Marshmallow/Michelin Man and don't want to move their arms very much.

Metals are complicated. You can't just say "this one is stronger than that one" because there are many kinds of "strength". And strength doesn't include things like hardness/flexibility.


We use aluminum in airframes because it provides specific advantages (specific strength, mostly) over steel. Mithral, however, is given as a super-metal that is simply better than steel, something that aluminum is most definitely not. I would go with Ti 6-4 instead as a mithral equivalent.

Titanium isn't "better" than steel anymore than aluminum is. Titanium is a "super-aluminium", not a "super-metal".

MukkTB
2012-02-18, 10:29 PM
Its a bad idea to take a standard airship into combat, being a big pop-able balloon that can catch on fire and all. I'd recommend some kind of levitation spell capable of huge weights. More than one if you need. Permanency if you need. Some kind of defense against dispel magic. NSEW movement could be accomplished by something as simple as sails or you could go for more magic.

Cerlis
2012-02-18, 11:21 PM
I think I heard something about once upon a time there was two silvers. True silver, and something else, it was called silver but there was some previous word, forget what.

But it was aluminum, and was more expensive and rare and thus more valuable.

interesting concept.

----------

Also the concept of using mithril for ships makes a whole lot of sense, though is really just an extension of "why make armor out of steel when you have mithril"

Ulysses WkAmil
2012-02-18, 11:37 PM
+1 to the "Alchemetical Mithril", I like this. I always thought of mithril being like another fictional metal, Rearden Steel, in Atlas Shrugged. But aluminium being as strong as mithril? If you're taking standard lore, a chainmail vest made of mithril would stand up against an arrow. I dobt aluminium plate mail would. Same goes to weapons. Aluminium is too soft.

Dr.Epic
2012-02-18, 11:52 PM
So I was thinking about Airships, as I usually do. And pondering how the cultures of my D&D world could get around the difficulties of building early 20th century style flying machines with the technology of a fantasy world. Sure you can just say "oh its magic." But wheres the fun in that?

It occured to me that as a light, strong metal Mithril would be the best material to build an airships frame. Although the vast cost would be prohibitive.

Of course this was also true of Aluminium, (from which airships are actually built). Up until the late 1800's aluminium was an extreamly rare and precious metal, more expensive than gold. Nowerdays we can manufacture it easily but this wasn't always the case.

So my airship building problem is solved, Alchemists have discovered a way to create mithril in large quantities (which will certianly have interesting effects on the economy of my world...).

Anyway this has led me to the interesting conclusion that Mithril was Aluminium all along. but no one has ever noticed before.

Discuss.

Aluminum isn't strong. Mithril is strong, light, and shiny - all traits shared by titanium.

kieza
2012-02-18, 11:52 PM
7075-T6 aluminum (T6 refers to the heat treatment, which is needed for using it in most aircraft structural issues) has its drawbacks, which do not correlate with Mithral's stats in D&D 3.5 (or anywhere, really).

1.) It's still not as stiff as structural steels. By far.
2.) That specific strength? It's per unit mass, which means that for a less dense material like aluminum, the same mass will be bulkier, which is bad for armor plating.
3.) Heat-treated, alloyed aluminum is no longer as magically impervious to corrosion as people believe it to be.
4.) It has worse fracture toughness qualities than many steels.

We use aluminum in airframes because it provides specific advantages (specific strength, mostly) over steel. Mithral, however, is given as a super-metal that is simply better than steel, something that aluminum is most definitely not. I would go with Ti 6-4 instead as a mithral equivalent.


You may know more than I do about metallurgy (I'm just an economist whose father ran a machine shop for a while), but I'm basing this off of an article which states 7075 has been used in vehicular armor, and has similar strength to steel at a lower weight. Is there any reason this wouldn't extend well to personal armor?

I'm not too concerned about hard-core simulationism; Just trying to get some alloy with roughly the same properties.


Tungsten Carbide is far too inflexible to be effective in most weapons - though arrowheads should be entirely functional. Sure, it works in modern stuff, but a sword? Sadly, no. Plus, the whole "several times heavier" detail is rather inconvenient.

The numbers I came up with said about twice as heavy, which is inconvenient but seems still usable. Why does inflexibility make it unsuitable for swords? Also, would it work as (heavy, uncomfortable) armor?

Xuc Xac
2012-02-19, 12:32 AM
7075 has been used in vehicular armor, and has similar strength to steel at a lower weight. Is there any reason this wouldn't extend well to personal armor?


Medieval style personal armor is designed to stop or redirect blows. Vehicular armor is usually designed to absorb all the energy of an attack and get blown apart or otherwise destroyed in the process because it's easy to replace the plates during maintenance. Ablative armor is great for something which is basically a box on wheels. It isn't such a good idea for something with a lot of moving joints like a person.


The numbers I came up with said about twice as heavy, which is inconvenient but seems still usable. Why does inflexibility make (tungsten carbide) unsuitable for swords?

A sword's material needs two main qualities: hardness and flexibility. Hardness equals sharpness and a soft blade gets dull quickly. An inflexible blade will break rather than bend when it hits something hard. These traits are usually incompatible so you have to find a balance between the two. A glass sword, for example, is the sharpest cutting edge known to science but it would snap under its own weight if you tried to swing it quickly.

Steel is the best material for a sword because it's possible to heat treat it to alter its properties in different parts of the blade. A good sword has a very hard edge and a flexible core.

Knaight
2012-02-19, 02:38 AM
Aluminum isn't strong. Mithril is strong, light, and shiny - all traits shared by titanium.

Mithril is at least as strong as the steel used in high quality weapons or armor, Titanium really isn't. The closest you can get to Titanium that would even be useful would be Titanium steel, which is still mostly iron - and even then, it's not a particularly good idea. Steel is actually very impressive stuff, and replacing it in situations where it's properties are particularly important (weapons, armor) is generally a bad idea.

Anderlith
2012-02-19, 06:28 AM
I always thought that Mithral was Titanium or Palladium. Aluminum doesn't have the right color or physical properties of Mithral

Ossian
2012-02-19, 06:40 AM
Structure and molecular orientation are just as important as the choice of materials, at least judging from the nano-stuff that populates the marvel verse. I would go for the iron-platinum alloy of the bleeding edge armour (Iron Man). It might not heal itself, but it should be durable, light and flexible. Then you realize that one ship is 10000000000000000 gold pieces and if you lose one in a crash test you are so done for. Then you realize that with the same worth in wood and good quality steel, you could have had an entire fleet.

My idea is that you should really go the Leonardo way. The biggest hurdle was not even technology. It was ideology. Once you think that flight is just a technical issue, albeit complicated, and not something that will anger the gods, then you are good too go.

Seb Wiers
2012-02-19, 11:06 AM
Bamboo, properly configured, can have properties on par with carbon fiber, and better than aluminum in terms of utility for an airship's structure. Using magic and alchemy, plus some good old fashioned horticulture techniques, you could easily grow it to exactly the sizes / shapes needed. Where bonding was required, alchemy would again comes to the rescue, with sovereign glue.

Morph Bark
2012-02-19, 11:26 AM
Mithril is harder than iron (hardness 15 vs iron's 10). Aluminum is much less dense than iron (2.7 g*cm^-3 vs iron's 7.9). Armor made of aluminum would be... not so good.

Hardness =/= density.

Beowulf DW
2012-02-19, 12:14 PM
Aluminum is a very weak metal compared to steel. For jets and such, yes, it is strong enough to support an airframe, but it's the lack of weight that makes it useful, not it's strength.

If mithral actually existed, it would be the holy grail of air travel. Stronger than steel but very light. Airships made of mithral could potentally survive crashes relatively intact.

cantdrawatall
2012-02-19, 12:29 PM
I agree with Beowolf there, In real life, mithral would be the best thing since sliced bread. The aerospace industry would eat that stuff up as fast as the producers could manufacture it, therefore forcing research into better methods of manufacture.

As to what the topic of discussion, aka what Mithral's real life equivalent would be, I'd have to say a titanium alloy of some type. Due to it's lightness, toughness, tensile strength, and heat resistance properties. Please do remember that titanium allow is mostly not titanium. it is so prohibitively expensive it is alloyed to iron and aluminum, as Mithral is also in my belief. 100% pure Titanium isn't really good for anything.

EccentricCircle
2012-02-19, 01:43 PM
Bamboo, properly configured, can have properties on par with carbon fiber, and better than aluminum in terms of utility for an airship's structure. Using magic and alchemy, plus some good old fashioned horticulture techniques, you could easily grow it to exactly the sizes / shapes needed. Where bonding was required, alchemy would again comes to the rescue, with sovereign glue.

Ooh, I like that idea.

I'm probably going to go down the Alchemical Mithril route for my game. a cheaper to produce metal which isn't up to spec for armour and weapon construction and so doesn't affect armour prices. But the idea of Bamboo airships appeals for some of the other parts of the setting which have a less european derrived culture. In the past light wood would have predominated. But this campaign is largely about the advance of technology, so Alchemical Mithril makes a good advance to focus a bit of the plot around.

Knaight
2012-02-19, 03:37 PM
Hardness =/= density.

However, density is important. Fundamentally, if one assumes identical volume density correlates directly to mass, and in regards to armor a reduction in mass implies a reduction in energy to move the mass, as applies to armor deformation.

Gavinfoxx
2012-02-19, 04:48 PM
Yea, Mithral is *better* than Titanium or Aluminum...

But, IMO, the REAL material in D&D would be Glassteel

Champions of Valor has the stats, I believe.

Half the weight of Iron, as strong as Adamantine, as much friction as glass... yea. Talk about your super material...

hamishspence
2012-02-19, 05:06 PM
It had even better stats in Races of Faerun, but Champions of Valor toned them down slightly.

What was present in Races of Faerun (that was dropped) - a nonmagical enhancement bonus (same as adamantine) and a Spot checks to spot the items, carried -4 penalty.

On the other hand, Champions of Valor considerably reduced the price of glassteel.

Mando Knight
2012-02-19, 08:10 PM
You may know more than I do about metallurgy (I'm just an economist whose father ran a machine shop for a while), but I'm basing this off of an article which states 7075 has been used in vehicular armor, and has similar strength to steel at a lower weight. Is there any reason this wouldn't extend well to personal armor?

I'm not too concerned about hard-core simulationism; Just trying to get some alloy with roughly the same properties.



The numbers I came up with said about twice as heavy, which is inconvenient but seems still usable. Why does inflexibility make it unsuitable for swords? Also, would it work as (heavy, uncomfortable) armor?Pretty much what Xuc said, I'll add a few more comments.

Medieval style personal armor is designed to stop or redirect blows. Vehicular armor is usually designed to absorb all the energy of an attack and get blown apart or otherwise destroyed in the process because it's easy to replace the plates during maintenance. Ablative armor is great for something which is basically a box on wheels. It isn't such a good idea for something with a lot of moving joints like a person.
Also 7075 isn't the primary material in vehicular armor. Military aircraft tend to use more titanium alloys (like Ti 6-4), and ground vehicles and heavier aircraft use composites, usually a system of layers of steel, titanium, ceramics, and/or depleted uranium. Al 7075 fills in for when such materials aren't practical for the given system.

Personal armor needs to be sufficiently hard, stiff, and thin. Aluminum, in order to get the stiffness of steel, would require greater thickness and thus much bulkier armor... which makes it cumbersome.

A sword's material needs two main qualities: hardness and flexibility. Hardness equals sharpness and a soft blade gets dull quickly. An inflexible blade will break rather than bend when it hits something hard. These traits are usually incompatible so you have to find a balance between the two. A glass sword, for example, is the sharpest cutting edge known to science but it would snap under its own weight if you tried to swing it quickly.

Steel is the best material for a sword because it's possible to heat treat it to alter its properties in different parts of the blade. A good sword has a very hard edge and a flexible core.Ceramics make good knives, but they have literally no durability in a combat situation, which is why metals are good. The Aztecs' "sword clubs" were essentially the best way to make a sword with a ceramic or similar (in this case, obsidian) blade: the blades were mounted on sticks, which had the toughness that the shaft of a melee weapon needs.

Soylent Dave
2012-02-19, 09:17 PM
But, IMO, the REAL material in D&D would be Glassteel

See that's just made me think of Transparent Aluminium (http://en.wikipedia.org/wiki/Aluminium_oxynitride)

(which would also be rubbish for use in weapons, incidentally)

While you're plundering the periodic table, can I recommend use of Francium for flaming swords (it ignites in air) and Technetium for poisoned (well, radioactive) blades.

(Francium might also work for 'phase swords' and the like, seeing as it is ludicrously unstable and is constantly trying to not exist any more)

warty goblin
2012-02-19, 09:56 PM
Ceramics make good knives, but they have literally no durability in a combat situation, which is why metals are good. The Aztecs' "sword clubs" were essentially the best way to make a sword with a ceramic or similar (in this case, obsidian) blade: the blades were mounted on sticks, which had the toughness that the shaft of a melee weapon needs.

Indeed, ceramics can be obscenely sharp, but are crazy easy to break. Back when I worked in an industrial kitchen one of the guys broke a square inch chunk out of the middle a ceramic knife just by tapping it into a cutting board, apparently with a very slight bit of torque.

erikun
2012-02-19, 11:52 PM
As others have pointed out, aluminium does not relate to mithril. I seem to recall from my old chemistry studies that aluminium is around 30% lighter than steel, but also 30% weaker. This means that pound-for-pound the two materials are roughly similar, but that an aluminium object would take up more volume.

This is handy for objects that require the rigidity of metal but do not require the full strength of steel and require rust resistance - soda cans and airplanes come to mind - but is not a good idea to replace steel armor that is already in danger of being punctured by existing weapons.

Others far more knowledgeable than I have already pointed out other problems with the equivalency.


And as a side note, I've always considered adamantine to be lead, or at least magically-treated lead. After all, it's denser, heavier, harder to work with, and far more resistant to damage. Or perhaps it would be magically-irradiated lead (that is, depleted uranium) and dwarves are naturally resistant to the magical radiation. :smalltongue:

Archpaladin Zousha
2012-02-20, 01:35 AM
In the first campaign I ever played in, this was EXACTLY the case. The setting was a post-apocalyptic Europe after technology had reached its apex and somehow caused a second Ice Age. Our characters were investigating the Mithral Mines, Thule's (the new name of the continent) main source of the metal, and we found that the mithral had odd red markings on it, and symbols, and we realized as players that what we'd found were soda cans and the mine was actually an ossified garbade dump. My paladin also recovered the ancient Six-Shooters of St. Murlynd (yes, the same Murlynd who made that famous spoon, which I later found in a sacred reliquary) in the mines and we discovered what would later become the main enemies of the campaign, the Clockwork Servants, a race of robots that lived in the Underdark that were returning to rescue their masters (the humanoid races, actually genetically altered humans millennia ago) and wipe out any mutant lifeforms that had evolved in the interim.

Later on my paladin used what aluminum he'd recovered to have a suit of full-plate made. :smallbiggrin:

Rockphed
2012-02-20, 02:37 AM
In the first campaign I ever played in, this was EXACTLY the case. The setting was a post-apocalyptic Europe after technology had reached its apex and somehow caused a second Ice Age. Our characters were investigating the Mithral Mines, Thule's (the new name of the continent) main source of the metal, and we found that the mithral had odd red markings on it, and symbols, and we realized as players that what we'd found were soda cans and the mine was actually an ossified garbade dump. My paladin also recovered the ancient Six-Shooters of St. Murlynd (yes, the same Murlynd who made that famous spoon, which I later found in a sacred reliquary) in the mines and we discovered what would later become the main enemies of the campaign, the Clockwork Servants, a race of robots that lived in the Underdark that were returning to rescue their masters (the humanoid races, actually genetically altered humans millennia ago) and wipe out any mutant lifeforms that had evolved in the interim.

Later on my paladin used what aluminum he'd recovered to have a suit of full-plate made. :smallbiggrin:

Somehow you always have awesome stories to tell. I must get a group back together to get some semblance of this sort of awesome.

Mando Knight
2012-02-20, 03:31 AM
And as a side note, I've always considered adamantine to be lead, or at least magically-treated lead. After all, it's denser, heavier, harder to work with, and far more resistant to damage.
Lead is easy to work with. It has a low melting point and high malleability/ductility. What's hard to work with is titanium, since it doesn't conduct heat well and thus has several quirks.

Adamantine is closest to starmetal/meteorite iron historically/mythologically (natural nickel-iron from ferrous space debris, higher quality than most other iron ores) and metallurgically probably closer to 300M steel (a high-quality, high-strength steel).

and we realized as players that what we'd found were soda cans

Later on my paladin used what aluminum he'd recovered to have a suit of full-plate made. :smallbiggrin:
...Of all the aluminum alloys... (this one's one of the worst for combat applications unless the world lacks steel weapons in general)

Jay R
2012-02-20, 11:43 AM
Anyway this has led me to the interesting conclusion that Mithril was Aluminium all along. but no one has ever noticed before.

Discuss.

Well. first of all, it's not true that no one has noticed before. I first heard this theory suggested in the 1970s. I rejected it then , for all the reasons given by others. Aluminum does not have the properties of mithril, except that it fits the generic phrase "lighter than iron".

In Tolkien's Middle-Earth, where mithril came from, there is magic. Therefore the laws of physics don't work as they do here. Mithril cannot be made to fit any real-world equivalent, for the same reasons elves and balrogs can't.

Tyndmyr
2012-02-20, 11:54 AM
Mixing up actual metallurgy, materials etc. with D&D can bring the headache real quick.

Anyway, I guess comparison could work, but mithril is generally, traditionally treated as something more "miraculous", like it's strong, resistant to most forces, hard etc. without any actual flaws.

Some reading (http://www.g2mil.com/aluminum.htm)

If anything, Mithril is straight up superior to aluminum. So, yeah, it could be used instead of it in an airship, and if anything, will be better than the original.

For instance, if it's stronger than aluminum, you could get away with using even less, and have an even lighter(or stronger) airship.

Gavinfoxx
2012-02-21, 05:37 PM
Yea. D&D's Mithral > Steel > Titanium > Aluminum, for personal armor and personal weaponry purposes... Some people have made personal titanium armor. It SUCKS. It's not as durable as steel for the same density, and the weight of steel actually helps its protective quality... Mithral, being a fanciful material, wouldn't have these issues...

Yora
2012-02-21, 06:17 PM
Mithral is TITANIUM. Titanium is as strong as steel but 45% lighter, roughly on par with mithral.

That's what I have been assuming for a long time.

Gavinfoxx
2012-02-21, 10:44 PM
The thing is, titanium is as strong for the same WEIGHT, not the same VOLUME.

So a 1/8" thick sheet of titanium is weaker than a 1/8" sheet of steel! In D&D remember, a 1/8" thick sheet of mithral is stronger than a 1/8" thick sheet of steel...

Rorrik
2012-02-22, 10:27 AM
I'm currently looking at an electromagnetics textbook that declares Mithril has a conductivity of 7*10^7, twice the conductivity of Aluminum. (I added the note, but that doesn't mean it's not in my textbook) So there's a another plus to mithril, unless you were intending it as an insulator.

I wonder at what temperature Mithril alloys can go superconductor.

Also, I add my approval to the "Alchemical Mithril" concept for the airships.

Tyndmyr
2012-02-22, 02:52 PM
However, density is important. Fundamentally, if one assumes identical volume density correlates directly to mass, and in regards to armor a reduction in mass implies a reduction in energy to move the mass, as applies to armor deformation.

True, but we also have to consider ablative armor options like ceramic.

These are usually fairly poorly represented in fantasy settings, though, so that's likely not a great problem. I wonder if this sort of thing really is worth modeling, though...I mean, would you wear awesome, light armor if it would shatter to dust after a few blows?

Jay R
2012-02-22, 03:08 PM
...I mean, would you wear awesome, light armor if it would shatter to dust after a few blows?

It's called an Armor spell, in 2E at least, and I use it constantly.

In the real world, it's called a motorcycle helmet.

Knaight
2012-02-22, 04:38 PM
True, but we also have to consider ablative armor options like ceramic.

These are usually fairly poorly represented in fantasy settings, though, so that's likely not a great problem. I wonder if this sort of thing really is worth modeling, though...I mean, would you wear awesome, light armor if it would shatter to dust after a few blows?
Very true. Honestly, the energy of deformation being discussed above is really only applicable to largely solid plates, meaning plate armor, breast plates, lamellar, and maybe scale. It breaks down for mail, and it breaks down for ablative armor in a big way - as at that point we suddenly care about the energy needed to break lots of chemical bonds, and not just the energy needed to heat chemical bonds so that they bend under force.

On the upside, ceramic armors basically don't exist in fantasy settings, so it is only breaking down with mail that actually matters.

It's called an Armor spell, in 2E at least, and I use it constantly.

In the real world, it's called a motorcycle helmet.
Bicycle helmets are actually closer. They tend to shatter after one solid hit, and the energy dispersed there is the energy that isn't killing you by going straight to breaking your skull and accelerating your brain into your skull to bruise it. That said, one can only expect to be hit a handful of times throughout their life, which is really not the same as armor in an actual combat situation.

Lapak
2012-02-22, 05:03 PM
True, but we also have to consider ablative armor options like ceramic.

These are usually fairly poorly represented in fantasy settings, though, so that's likely not a great problem. I wonder if this sort of thing really is worth modeling, though...I mean, would you wear awesome, light armor if it would shatter to dust after a few blows?


It's called an Armor spell, in 2E at least, and I use it constantly.

In the real world, it's called a motorcycle helmet.Or ceramic strike plates that we use today in bullet-resistant armor. They are explicitly designed to take a hit and then be replaced, and the armor is designed so that replacing the plate doesn't mean replacing the whole thing.

As to the 'would you wear it' question, we can see that the answer is yes - PROVIDED that you're part of a supply system that can give you spares easily and the armor is designed such that it doesn't suffer complete failure but is fixable.

warty goblin
2012-02-22, 08:12 PM
As to the 'would you wear it' question, we can see that the answer is yes - PROVIDED that you're part of a supply system that can give you spares easily and the armor is designed such that it doesn't suffer complete failure but is fixable.
I'm not sure ablative armor would be particularly wise. There's quite a few medieval battles that spring immediately to mind where both infantry and cavalry were required to cover significant ground in formation under arrow-storm. Because well made steel armor isn't shot to hell after one or two arrow strikes, this wasn't a bloody massacre, but with a ceramic plate designed to shatter after impact...

Rorrik
2012-02-22, 10:13 PM
I'm not sure ablative armor would be particularly wise. There's quite a few medieval battles that spring immediately to mind where both infantry and cavalry were required to cover significant ground in formation under arrow-storm. Because well made steel armor isn't shot to hell after one or two arrow strikes, this wasn't a bloody massacre, but with a ceramic plate designed to shatter after impact...

True, while in modern situations we do more about not getting hit, in many fantasy situations, like bashing at eachother with swords, the ablative armor would quickly become useless. But I wonder how well it would stand up to something with more weight in contrast to a bullet anyway. A bullet does most of its damage by being small and so has less energy to disperse. A sword does a lot of its damage by being heavy and armor good against bullets might not do much to mitigate damage.

warty goblin
2012-02-23, 12:16 AM
True, while in modern situations we do more about not getting hit, in many fantasy situations, like bashing at eachother with swords, the ablative armor would quickly become useless. But I wonder how well it would stand up to something with more weight in contrast to a bullet anyway. A bullet does most of its damage by being small and so has less energy to disperse. A sword does a lot of its damage by being heavy and armor good against bullets might not do much to mitigate damage.

A bullet has a lot more energy than a sword strike; although they have very little mass they are travelling stupidly fast.

Swords tend to do their damage not so much from weight, as from either thrusting with the point or cutting with the edge. Now in order to be effective in those roles, some mass is obviously required, but as the use of draw cuts demonstrates, a lot of trauma can be caused by the edge with very little energy behind it.

What makes me wonder about ceramic armor in a good old fashioned medieval battle is that most ceramic armors dissipate energy by breaking. The high quality steel armors of the middle ages dissipated energy by deforming and springing back into shape, which meant that they were good for multiple impacts, but I'm not sure the same is necessarily true of ceramics. It would be a poor choice of body armor if all your plates got broken while under arrowstorm on the advance, and then somebody smacked you in the gut with a pole hammer. Even if it survives the arrows, the polehammer will break it, and then your armor is shot, you're probably winded from the blow at the very least, and the guy who hit you is all of eight feet away. I'm not sure that you're worse off in this scenario than you would be in steel, but you're certainly not better off.

(There's also the matter of helmets. With firearms the head is a hard target, with a striking weapon it's a very easy one. Helmet plates breaking is not an idea I find particularly encouraging.)

Jay R
2012-02-23, 09:50 AM
I suppose that this will mark me as irredeemably old-school, stuck in the ways of early D&D, but the reason not to include ablative armor as anything but a magic spell is that there was no medieval ablative armor.

Lapak
2012-02-23, 09:58 AM
I suppose that this will mark me as irredeemably old-school, stuck in the ways of early D&D, but the reason not to include ablative armor as anything but a magic spell is that there was no medieval ablative armor.Super old-school D&D included things like a wizard with revolvers (http://en.wikipedia.org/wiki/Murlynd) and crashed spaceships with rayguns in them (http://en.wikipedia.org/wiki/Expedition_to_the_Barrier_Peaks), so I'd say sticking ferociously to medieval technology isn't really all that old-school.

That said, it could be argued that weapons were designed specifically to turn shields into ablative armor pretty early; I'm think of the roman javelins that were designed to stick in shields here. If you don't have a shield, you got speared; if you do have a shield, the shield has just become much less useful AS a shield. :smallwink:

Jay R
2012-02-23, 10:33 AM
Super old-school D&D included things like a wizard with revolvers (http://en.wikipedia.org/wiki/Murlynd) and crashed spaceships with rayguns in them (http://en.wikipedia.org/wiki/Expedition_to_the_Barrier_Peaks), so I'd say sticking ferociously to medieval technology isn't really all that old-school.

Neither made it into published rules until AD&D. All non-magical armor was based on a medieval design. (Admittedly, the way shields and armor worked was as inaccurate as any set of D&D rules, but it was still plate, chain, or leather, not ceramic.)


That said, it could be argued that weapons were designed specifically to turn shields into ablative armor pretty early; I'm think of the roman javelins that were designed to stick in shields here. If you don't have a shield, you got speared; if you do have a shield, the shield has just become much less useful AS a shield. :smallwink:

That isn't ablative armor, designed to protect by taking the damage itself. That's an attempt to make permanent armor fail.

Lapak
2012-02-23, 10:39 AM
Neither made it into published rules until AD&D. All non-magical armor was based on a medieval design. (Admittedly, the way shields and armor worked was as inaccurate as any set of D&D rules, but it was still plate, chain, or leather, not ceramic.)Murlynd - with his guns - goes all the way back to the proto-game that wasn't even D&D yet. NOTHING was published yet; claiming he didn't get published until AD&D seems to be missing the point. The people creating the game were working off a pulp-oriented framework that includes a lot of swords-and-rayguns and/or post-apocalypse material. Absolutely, they started from a straight-up medieval tech framework in Chainmail, but the minute they started expanding on it pure medievalism went out the window for good.

Note that I'm NOT saying that you should include ceramics, or ablative armor, or rayguns, or anything you don't want in your campaign. I'm just saying that including such elements is entirely within the bounds of 'old-school' D&D.


That isn't ablative armor, designed to protect by taking the damage itself. That's an attempt to make permanent armor fail.Which is why I included the winking emoticon. It wasn't meant as a serious argument. :smallsmile:

Deepbluediver
2012-02-23, 02:05 PM
The original quote from Tolkien in LotR is (according to wikipedia):

"Mithril! All folk desired it. It could be beaten like copper, and polished like glass; and the Dwarves could make of it a metal, light and yet harder than tempered steel. Its beauty was like to that of common silver, but the beauty of mithril did not tarnish or grow dim."
The first time I read I also thought it sounded a lot like aluminum, but as other posters have pointed out, aluminum has somewhat different properties than steel and I now think that Titanium would fight the mundane equivalent better.

One of Aluminum's best features is it's resistance to corosion and rusting and increased flexibility, which makes it less vulnerable to stress fractures (from things like changes in pressure and temperature). That's a major part of the reason you find it in aircraft and other non-industrial capacities.

Getting back to EccentricCircle's original idea, it might help if we had more info on exactly what kind of airship's we where thinking about, and what the general magic/magitek level of the world was.
If you have derigibles and blimps, rather than hydrogen or helium have them held aloft by air elementals or something.
If you want actual ships-that-fly, like in (fill in your story/media of choice) Skies of Arcadia then I would suggest a combination of engineering and magic. Most technologically complex machines include a variety of metals and alloys for various parts. The support structure might be aluminum/mithral, with an adamantine engine and steel armaments. When you start putting that much thought into something, I really don't think your players or DM is gonna question it too closely.

Rockphed
2012-02-23, 03:02 PM
I'm currently looking at an electromagnetics textbook that declares Mithril has a conductivity of 7*10^7, twice the conductivity of Aluminum. (I added the note, but that doesn't mean it's not in my textbook) So there's a another plus to mithril, unless you were intending it as an insulator.

I wonder at what temperature Mithril alloys can go superconductor.

Also, I add my approval to the "Alchemical Mithril" concept for the airships.

Typically, good conductors do not go super-conductor. In fact, what makes something a good normal conductor would make it a really bad super-conductor. Essentially, super conductors need a fermi surface that has lots of states on it with the same kinetic energy.

Also, how did you decide that mithral should be the BEST CONDUCTOR EVAR? I mean part of why metals are so shiny is because they are good conductors, but gold and copper(the only two elemental metals that aren't silver colored) are two of the 3 best conductors.

Jay R
2012-02-23, 05:32 PM
... and I now think that Titanium would fight the mundane equivalent better.

I have trouble processing the idea of the mundane equivalent of mithril. I know what you mean, but an equivalent of mithril is by definition not mundane.

Why is there so much interest in denying the notion that mithril is from a magical world, not a mundane one?

EccentricCircle
2012-02-24, 03:52 PM
Getting back to EccentricCircle's original idea, it might help if we had more info on exactly what kind of airship's we where thinking about, and what the general magic/magitek level of the world was.

The Technology level of the world would be late medieval / early renaisance but for the presence of magic which is triggering an industrial revolution. gunpowder, printing presses and telescope have been invented. Large industrial revolution style machines are now being built using steam engines or water wheels. some are driven by magically sustained perpetual motion machines. using magic on an industrial scale normally depletes the world's magical Ambience burning a magicless hole in the vicinity of the machine. but more energy can be channeled into the world from vast, naturally occuring reservoirs on the higher planes (called the Aethers).(actually make that which are the higher planes) Magical Lanterns called Aetherlights are used to draw magic from the Aethers into the magical Ambience of the world to sustain it where industrial scale magic use would otherwise burn it away.

Elementals may exist, but this has not yet been confirmed within the game and i'm not going to say anything one way or the other as my players might be watching. if they do exist then its likely that Aetherlight use is destroying their natural habitats though!

the airships are going to be similar to those used in the 20's the 30's on earth. Massive dirrigibles probably filled with helium, with a lightweight skeleton of... Alchemical Mithril! they will not be the conventional flying ship sort seen in eberron and similar settings.
I'm slowly populating a wiki as the game progresses so that the players can look things up. if anyone is interested in the details it can be found here:
http://aetherlight.wikispaces.com/

Gavinfoxx
2012-02-24, 07:16 PM
Why do people not respond to the idea that mithral is BETTER than Titanium? Seriously, every description of it I have ever seen gives it properties BETTER than those of Titanium!

fusilier
2012-02-25, 02:45 AM
One of Aluminum's best features is it's resistance to corosion and rusting and increased flexibility, which makes it less vulnerable to stress fractures (from things like changes in pressure and temperature). That's a major part of the reason you find it in aircraft and other non-industrial capacities.

Actually, I think one of the problems with Aluminum is that it's more vulnerable to stress fractures than steel. Steel can be tempered to make good springs, that should be able to handle bending, warping, tension, etc. Yet, I'm not aware of aluminum springs. I think aluminum frame aircraft have to be inspected frequently, especially at well known key stress points, for stress fractures.

Some light aircraft actually have tubular steel fuselage frames.

As for the original post. I pointed out that wooden zeppelin type airships were built, and most early dirigibles had little to no aluminum in them. There does seem to be a practical limit to the size of a wooden zeppelin which was less than an aluminum one. Anyway, if Mithral is as light as aluminum, but has steel like properties, it would probably be superior to aluminum when used as a structural component in aircraft of any sort.

Does this mean Mithral would be relatively cheap and commonplace?

ericgrau
2012-02-25, 02:54 AM
Aluminum alloy has strength similar to mild steel (but weaker than high strength steel). In general aluminum is a lighter alternative to steel in equivalent strength applications. Especially in aircraft where it's pretty much the norm and anything heavier like steel is commercially unacceptable. The exceptions are exceptions. The only practical drawback most of the time is the higher cost of aluminum, which is what limits its use to certain pieces and not the whole chasis in all but the fanciest of cars.

D&D hardness is not engineering hardness. It's more like engineering toughness - the ability to absorb some impact before taking damage - in which aluminum does pretty well.

So... ya, it could be a good match for D&D purposes. I think people see the cheaper and thinner aluminum used for cans and don't realize how exotic it is in construction. Titanium might be a better match though since it's lighter and stronger. Also way more expensive.

Aluminum used to be rare and expensive, more expensive than gold I think, until electrolysis. So if you claim aluminum = mithril then you'd need a steampunk tippyverse with abundant magical electricity to get (relatively) cheap mithril.

EccentricCircle
2012-02-25, 06:15 AM
Aluminum used to be rare and expensive, more expensive than gold I think, until electrolysis. So if you claim aluminum = mithril then you'd need a steampunk tippyverse with abundant magical electricity to get (relatively) cheap mithril.

Precisely, if you have magi capable of casting electricity based spells then it should be possible to develope electrolysis a lot earlier on.

Tetsubo 57
2012-02-25, 08:50 AM
I prefer the trope of liftwood for airships.

For me, mithril is as hard as steel but half the weight. Adamantine is twice as hard as steel and twice the weight. That's as close as I get to making real world comparisons.