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Magic System

One of my magic systems consists of the ability to magically synthesize a material in a given shape. The material can be any one of the elements from hydrogen all the way up to gold, or one of a small number of molecules (such as water, sugar, and salt). Only one kind of each material can be produced using magic. For example, all iron produced by any iron-synthesis spell will be chemically and structurally identical to one another. When a spell is cast, the material will suddenly spawn into existence in front of the user, with whatever was in the space it now occupies being removed from existence.

Question Info

When an iron-synthesis spell is cast, the iron produced will be chemically pure (i.e 100% iron, not just 99.99...%) and structurally homogenous. That means the iron's crystal structure will be identical throughout the produced volume. In other words, the iron will have none of the grains, cracks, or imperfections we would expect from iron produced through natural means. From my research I believe the produced iron should be ferrite (as that is the allotrope that is stable at 'normal' pressures and temperatures), but without the corresponding grain structure or dissolved carbon.

The Question

With that information, what material properties would be expected of my magically produced iron?

Material properties of particular interest would be strength, hardness, ductility, malleability, and conductivity.

I understand nobody will be able to provide hard numbers as this is a material which cannot be produced in reality, so I would be happy with logically-reasoned comparisons to existing forms of iron.

My Educated Guess

From what I have researched, I think such a metal would be very soft, and also much more brittle than regular iron. This is because, from what I have understood from Steve Mould's video it is grain size that mediates malleability in iron. With no grains and therefore no dislocations, I would expect the material to be less malleable. Additionally, high-purity iron is very soft.

On the other hand, AlexP pointed out such a material would be monocrystalline iron, which apparently has tensile strength well into the gigaPascal range.

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  • $\begingroup$ When you say that "the iron's crystal structure will be identical throughout the produced volume", do you mean that the object is an iron monocrystal, or only that all the iron in the object is α-iron (aka ferrite). If it is ordinary metallic iron, it is a relatively soft metal, with very well known mechanical properties. If you mean a monocrystal, well, nobody has ever seen one -- and it would be very unlike what we normally call iron. $\endgroup$
    – AlexP
    Jul 1, 2023 at 19:19
  • $\begingroup$ @AlexP I had not come across that term before you mentioned it, but I suppose I am asking after the properties of monocrystalline iron. It seems they do exist real-world, but only as nanoparticles or 'whiskers'. That said, I'm not sure how easy it would be to extrapolate the properties of those two structures to e.g a sword-shaped chunk of monocrystalline iron $\endgroup$
    – M S
    Jul 1, 2023 at 21:05
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    $\begingroup$ The point is that real-life metals are almost always polycrystalline, being composed of many tiny crystallites. Metallic monocrystals have some particular applications, such as some high-performance turbine blades. Sometimes they have surprising properties: for example, monocrystalline copper is a better electrical conductor than any other metal. On the other hand, monocrystals are obviously not isotropic, which may be undesirable for many applications. $\endgroup$
    – AlexP
    Jul 1, 2023 at 21:43
  • $\begingroup$ @AlexP I don't think monocrystals should be inherently anisotropic. From what little I researched after reading your comment that seems largely dependant on the crystal structure itself as well as which properties you are measuring. For example, this paper mentions monocrystalline silicon to be isotropic (at least when it comes to certain properties). $\endgroup$
    – M S
    Jul 1, 2023 at 22:08
  • $\begingroup$ Some monocrystals (depending on the crystal system) can be isotropic for some properties, mostly electrical and optical. Not so much for mechanical properties. $\endgroup$
    – AlexP
    Jul 1, 2023 at 22:49

2 Answers 2

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Heart of a very heavy star which instantly crumbles to a pile of rusty powder with chunks of ferrite

At regular pressure, iron has less than a handful of alotropes with different solubilities to carbon. At room temperature the most common alotrope is the one called ferrite. Wikipedia says it has a solubility to carbon of around 0.02%. You can find all of its other properties such as ductibility, toughness etc here.

You can only find purer forms of iron in very extreme environments, such as the core of dying stars that are too heavy to become red giants but not heavy enough to become neutron stars or black holes. They will fuse all the mass in their core into ever heavier elements until they reach iron, and then the fusion stops and the star spends astronomical time cooling down.

If your iron is magically stable, then scientists will have a field day studying it. We can only guess its properties but I wager they would be similar to those of wrought iron.

Most likely though, it will instantly try to become its most stable allotrope at regular pressure and temperature, which will draw a lot of oxygen and carbon dioxide in. You will have chunks of ferrite, maybe a lot of hematite, and surely a lot of rust. And it will be hotter than it was when it got summoned, but probably not red hot.

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    $\begingroup$ Surely carbon is only prevalent in real-world iron due to how it is found, processed, and produced? I don't see how gases could be 'sucked into' a chunk of pure iron, other than the surface of the material reacting to form iron oxide. From what I have researched ferrite grains and pretty much pure iron anyway, with carbon mostly being found along grain boundaries. $\endgroup$
    – M S
    Jul 1, 2023 at 21:02
  • $\begingroup$ *ferrite grains are $\endgroup$
    – M S
    Jul 1, 2023 at 21:07
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    $\begingroup$ Why instantly? Rust is more stable than regular iron in an oxygen atmosphere, but a lump of iron doesn't just instantly turn into rust. $\endgroup$
    – N. Virgo
    Jul 2, 2023 at 6:08
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I'm not sure how useful it would be

Obligatory 'Not a Metallurgist' - My understanding is that many of the things that we do with Iron that are useful are due to the impurities - such as adding varying amounts of Carbon etc.

Outside of a Lab and curiosities - I don't know if it would be much better than regular Iron.

There might be some fringe uses where absolute purity might be required - but I can't think of any that something like 99.999% pure ingot wouldn't be able to do.

Interesting question - perhaps there's other elements where significant increase in purity could be great.

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  • $\begingroup$ I don't mind if it turns out to be a relatively useless material, in fact I was expecting it to be quite soft, as apparently pure iron has a hardness similar to that of aluminium. Ultimately my goal with the question is finding out whether someone could directly produce decent weapons/equipment using an iron-synthesis spell, or whether it would have poor enough properties that it makes more sense for iron to be synthesized as a raw material, which is then processed into steel (or simply better iron) by a blacksmith. $\endgroup$
    – M S
    Jul 1, 2023 at 21:10
  • $\begingroup$ @MS - I think have a Magically synthesized steel, where you could precisely control the crystal lattice structure and the distribution of Carbon etc. would be more useful - especially if it could be synthesized into custom shapes - essentially all the benefits of billet manufacturing, but with the 'ease' of casting in a mold. Or being able to magically combine Alloys so you have a razor sharp and hard edge for a sword, but a flexible core. $\endgroup$ Jul 1, 2023 at 21:25
  • $\begingroup$ I'm currently trying to simplify the magic system as much as I can, with the only variables being shape, size, material, speed, direction, and temperature. I was initially going to have people need to specify the number of neutrons, protons, and electrons in an atom of the material, as well as the chemical formula and structure, such that spells could be used to synthesize pretty much any material in existence, but that ultimately feels too complicated, and I don't know enough about the interrelated topics to know exactly how everything should be defined or how to keep everything consistent. $\endgroup$
    – M S
    Jul 1, 2023 at 22:02
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    $\begingroup$ I suppose that could be a separate question on its own. "How few variables are needed to describe any known material?" $\endgroup$
    – M S
    Jul 1, 2023 at 22:14

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