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Dr paradox
2019-07-30, 07:05 PM
So, I got to thinking about that well worn trope about the ancient sword of a forgotten culture, whose knowledge of metallurgy and craftsmanship is lost to the modern time. Damascus Steel would probably be the current equivalent.

My question is, what's the modern equivalent that we could make today? With the height of modern technology and material sciences, what's the greatest sword that we could make that could be dug out of the rubble three thousand years from now by a fur-wearing barbarian, to whom "America" is the name of an ancient titan who did cataclysmic battle at the dawn of the modern age? What would that barbarian's advantages be over his (let's say) early bronze age contemporaries?

Mr Beer
2019-07-30, 08:26 PM
I don't think we can make a better sword than they were making 500 years ago. The best sword material was, and is, good quality steel. There is no modern wonder material that supplants steel for sword-making.

We could probably make a rust-proof blade that would last a long time, not sure about 3000 years. High quality steel is better than bronze but not better in the sense of being some kind of auto-win device.

The way to distinguish the sword might be to make it a greatsword because I don't think bronze was used to make 5'+ long blades. So that would be pretty cool.

Lord Lemming
2019-07-30, 09:21 PM
I don't think we can make a better sword than they were making 500 years ago. The best sword material was, and is, good quality steel. There is no modern wonder material that supplants steel for sword-making.


Steel is still the best sword material around, but even a fairly typical modern steel is better than any steel that was available 500 years ago. How much better; I'm not sure, but the difference between a sword made of the best steel available 500 years ago compared to today is probably more noticeable when it comes to maintenance and long-term durability, and less of a dramatic advantage in a 1-on-1 fight. The big difference today is that steel is far cheaper and more easily worked. A modern sword made out of high-quality steel by a master smith is at least as good as any historical sword, probably a little bit better, but costs somewhere around the mark of $1000-$2000, where historically a sword cost more than a house.

TripleD
2019-07-30, 09:23 PM
Maybe not a sword, but with modern material science I’m pretty sure we could make a “mithril” equivalent in terms of armor. Lightweight, but flexibile and able to take a lot of punishment.

No brains
2019-07-30, 09:44 PM
One of the complications of this trope is that swords are not static things. They chip, wear, and rust so maintenance is important. Finding a sword of a lost super-material is going to be cool for a little bit, but without the knowledge of that material, it will be hard to repair the sword when it inevitably wears.

Maybe if I had to spitball... perhaps something like an axe with a titanium head and lead weights to compensate for the weight. Maybe something with iridium or osmium.

A suit of titanium or high-end aluminium plate would probably make someone really happy for a while. The inevitable dents will probably diminish its usefulness after a while, but it would be a fun time being sword-resistant for half the weight.

Mechalich
2019-07-30, 10:09 PM
Titanium knives are a thing that we make - they're used by scuba divers because of the corrosion resistance. That might not work for swords, but you could certainly make spearheads out of them if you wanted, and they would last an awfully long time even though they wouldn't necessarily be any better than steel swords (in fact, because titanium is comparably difficult to sharpen, they'd actually be harder for a successor society to use in some ways).

Of course, the modern sword is actually a firearm, and so a more interesting question might be whether we could leave high-quality guns behind for future generations. Modern military grade weapons are built from durable metals and plastics and could go an awful long time without degrading. The trick is the gunpowder, which looses efficacy over time. The recovery of current-era military weaponry is a major plot point in Joel Abercrombie's Shattered Sea trilogy, but I think he just ignored the gunpowder issue.

Xuc Xac
2019-07-30, 11:00 PM
Maybe if I had to spitball... perhaps something like an axe with a titanium head and lead weights to compensate for the weight.

Compensate for what weight? You only want a tree felling ax to be heavy because trees don't dodge and wood is harder than meat. Against mobile enemies, speed is the important thing. Battle axes were fairly quick and light. They were made to cut meat, not wood, so the bit looks more like a kitchen knife than something you'd use to chop a tree down.

Balyano
2019-07-30, 11:19 PM
Maybe the alloy of 3 parts titanium to 1 part gold. Has two different crystalline structures, alpha and beta. The beta is made under higher temperatures. Apparently the stuff weighs nearly identically to steel, is incredibly durable and will never corrode or tarnish, bonus for looking like a gleaming golden sword, probably never needs polished. The only problem is I have no info on the specifics of its properties, like tensile strength. But considering that both the titanium and the alloy are made in an oxygen free environment, and I think electricity is involved, probably something a medieval society would not have an easy time recreating. Make it a flamberge and claim it is literally a piece of sunfire.

Lord Lemming
2019-07-31, 07:11 PM
Maybe the alloy of 3 parts titanium to 1 part gold. Has two different crystalline structures, alpha and beta. The beta is made under higher temperatures. Apparently the stuff weighs nearly identically to steel, is incredibly durable and will never corrode or tarnish, bonus for looking like a gleaming golden sword, probably never needs polished. The only problem is I have no info on the specifics of its properties, like tensile strength. But considering that both the titanium and the alloy are made in an oxygen free environment, and I think electricity is involved, probably something a medieval society would not have an easy time recreating. Make it a flamberge and claim it is literally a piece of sunfire.

I just looked that up. That is... incredibly cool. Researchers only figured this stuff out about three years ago... and Iron Man made his suit out of a gold-titanium alloy back in 2008. It's four times harder than typical titanium, though I don't know how strong it is. Hardness isn't everything, a sword that's too hard is also brittle; swords need some flexibility as well. The best swords are treated so that the exterior of the blade is hard, and the core of the blade is flexible. I don't know if this titanium / gold metal can be treated the same way or not, but if it could...

Now I have an idea for weapons created by a class of being in my fantasy setting who have exceptional knowledge of the natural world... forged by secret techniques, golden like the sun, durable beyond compare, never tarnishing, and completely within the bounds of the real world.

No brains
2019-07-31, 07:29 PM
Compensate for what weight? You only want a tree felling ax to be heavy because trees don't dodge and wood is harder than meat. Against mobile enemies, speed is the important thing. Battle axes were fairly quick and light. They were made to cut meat, not wood, so the bit looks more like a kitchen knife than something you'd use to chop a tree down.

Not to make it THAT heavy, certainly. Though steel does add some weight and getting the axe to feel like a steel one may be important. I guess it depends on the kind of axe to a degree- if it were a poll axe with a spike or hammer opposite the blade, the leverage and weight of the haft might be enough.

I was probably getting mixed up because lack of weight is an argument I once heard for why titanium isn't used in swords.

Mechalich
2019-07-31, 08:34 PM
Now I have an idea for weapons created by a class of being in my fantasy setting who have exceptional knowledge of the natural world... forged by secret techniques, golden like the sun, durable beyond compare, never tarnishing, and completely within the bounds of the real world.

The trick with something like this is that it's not just a matter of knowledge. You can know that titanium exists, heck you could be holding a lump of ilmenite in your hand, but this won't provide you with the technology necessary to isolate the metal in a form you can actually use. Historically, the existence of titanium was known for a full century before the Hunter Process was invented in 1910 to isolate it - and to be able to conduct the Hunter process you need some means of producing an inert atmosphere at 1,000 C and a source of pure sodium. That requires a whole suite of other technologies (electrolysis for one, which means you need electricity too).

As a result, any culture with the ability to perform advanced metallurgy or some other technical process several tech levels ahead of everyone else, has to be advanced in order areas as well. The only way around this is for the culture to have access to a very rare native deposit of the relevant materials in elemental form - a good historical example is found in the history of Pencils (https://en.wikipedia.org/wiki/Pencil#Discovery_of_graphite_deposit), in which the discovery of a unique large native graphite deposit in England allowed for a monopoly on the production of pencils until a century later when a process was devised to make them from graphite powder. Native titanium is super rare, but perhaps a deposit sufficient to make a few weapons might be found (possibly from a meteorite).

Cikomyr
2019-07-31, 08:54 PM
If we are resigned to either using the best steel, or perhaps using that fancy crystallized Ti-3 Au Beta alloy mentioned above, maybe we can consider how modern technology could make a sword awesome outside of the sword itself.

I always like, in Arthurian tales, how Exalibur's scabbard was actually more powerful than the sword itself.

Could we design a super fancy scabbard that does the sword maintenance automatically? Resharpens the sword and repair breaks?

Max_Killjoy
2019-07-31, 10:51 PM
Can that Ti-Au alloy mentioned above "spring" like steel? One of the things about good steel, well worked, is that when you bend it, it returns to shape... as opposed to say a lot of reports of bronze swords having to be straightened after they were bent in combat.

Can that alloy be made to hold a sharp edge? One of the things about good steel, well worked, is that it holds an edge that's both sharp and durable.

Blackhawk748
2019-07-31, 11:11 PM
I mean, we could theoretically make some sort of crazy carbon nanotube thing in the near future. It'd be black except for the cutting edge, but even that would be highly resistant to corrosion

Squire Doodad
2019-07-31, 11:15 PM
Frankly, the sword as a blade has been improved noticeably but that's a result of refined processes as opposed to improved materials.

Aside from some futuristic tech, having a sword is...still a sword. You can do interesting stuff with the grip or the scabbard and have that translate to improved swing speed and swing accuracy and such, but the blade itself is not that different in comparison to a long time ago.

Lord Lemming
2019-08-01, 01:20 AM
Can that Ti-Au alloy mentioned above "spring" like steel? One of the things about good steel, well worked, is that when you bend it, it returns to shape... as opposed to say a lot of reports of bronze swords having to be straightened after they were bent in combat.

Can that alloy be made to hold a sharp edge? One of the things about good steel, well worked, is that it holds an edge that's both sharp and durable.

About springiness, that was my question too. I don't know the answer, and I suspect there may not be an answer floating around out there. After all, a new, experimental lab-created material made out of gold and titanium probably hasn't had very much testing done on it. Even if it can be made to be springy, no blacksmith today knows how to work it effectively.

As for the sharp edge, yes. Reportedly, this stuff is so hard that the people working with it tried to grind it down with diamond grit, and couldn't.

GrayDeath
2019-08-01, 06:19 AM
I mean, we could theoretically make some sort of crazy carbon nanotube thing in the near future. It'd be black except for the cutting edge, but even that would be highly resistant to corrosion

I am always in Favour of replicating Gurthang. ;)

Cikomyr
2019-08-01, 06:53 AM
About springiness, that was my question too. I don't know the answer, and I suspect there may not be an answer floating around out there. After all, a new, experimental lab-created material made out of gold and titanium probably hasn't had very much testing done on it. Even if it can be made to be springy, no blacksmith today knows how to work it effectively.

As for the sharp edge, yes. Reportedly, this stuff is so hard that the people working with it tried to grind it down with diamond grit, and couldn't.

All right, it's hard, but is it brittle? A sword that shatters its edge after a few hit won't last the test of time.

Lapak
2019-08-01, 09:23 AM
If we are resigned to either using the best steel, or perhaps using that fancy crystallized Ti-3 Au Beta alloy mentioned above, maybe we can consider how modern technology could make a sword awesome outside of the sword itself.

I always like, in Arthurian tales, how Exalibur's scabbard was actually more powerful than the sword itself.

Could we design a super fancy scabbard that does the sword maintenance automatically? Resharpens the sword and repair breaks?
See, this idea I like a lot, even if it is less 'our current technology' and more 'sci-fantasy.' A scabbard that is essentially a mini-forge, equipped to generate magnetic fields inside that are powerful enough to soften steel and refined enough to realign molecules into the desired structure with no flaws, cracks, or inclusions. Plus a system to draw out the heat in a controlled manner and ensure it is hardened properly. A 'magic' scabbard that reforged its blade like new every time you use it.

toapat
2019-08-01, 10:32 AM
The best possible sword manufacturable atm would be a pure Ti-95 (an aerospace alloy) blade and guard with composite grip, as TI-95 is as good as Tool Steel for retaining an edge while being as Tensile as 1095 springsteel for deformation, while only weighing about 2/3rds the weight of steel. The Titanium Gold alloy that was discussed is going to have the same embrittlement problem all Ti-Au alloys have which is material embrittlement, which while not important for a small number of swings, will matter as a long lasting relic.

The best possible sword theoretically possible in currently mass producable materials would use a Foil core surrounded by a titanium mass, with the foil being used to form the central edge of the blade, and being any choice of Tungsten, Chromium Steel, or ideally Boron Nitride.

The problems with forging a sword out of titanium IRL is that titanium passively hardens from cooling from thermal load, and Ti-95 is abrasion resistant by several orders of magnitude more then any steel used for weaponsmaking. Grinding the weapon embrittles the weapon through work hardening which cannot be tempered easily, and grinding the weapon generates extreme heat relative to a similar size weapon. To compare Man at Arms made Wolverine Claws a few years ago, and belts that lasted them normally a month, lasted 10 minutes on the titanium.

Max_Killjoy
2019-08-01, 10:54 AM
The best possible sword manufacturable atm would be a pure Ti-95 (an aerospace alloy) blade and guard with composite grip, as TI-95 is as good as Tool Steel for retaining an edge while being as Tensile as 1095 springsteel for deformation, while only weighing about 2/3rds the weight of steel.


Do those insisting that there's nothing better than steel for making swords not know about this alloy, or is there some other property where steel still has a clear advantage?

Willie the Duck
2019-08-01, 11:46 AM
Do those insisting that there's nothing better than steel for making swords not know about this alloy, or is there some other property where steel still has a clear advantage?

Titanium is has a higher tensile strength than steel, but does not have the same ability to resist sheer. You would actually have to put more weight back into the blade to make it durable, reducing the weight-savings. It also has a wildly different density-per-strength profile, meaning that you would have a bit of a 'Final Fantasy' sword if you were trying to make a sword with the same strength and durability as a high-end steel sword, which sounds cool but probably makes it harder to make it actually combat effective. Mostly, it is that titanium is not naturally good at ede-holding, and can't be heat-treated as steel can be to improve this. Toapat suggests that TI-95 "is as good as Tool Steel" (not necessarily the best comparator, since we really want to compare it to sword steel). I'm certainly not an expert, but this surprises me. The old adage has been that titanium makes a great structural member in things like airplanes, since tensile strength per weight (along with not having any keystone vulnerabilities, such as being completely inflexible or the like) and lack of corrosion are primary concerns there, but modern steel is still the king of blades... and each blade is going to have their own requirements -- small pocket knives, for instance, are enhanced by some vanadium in the steel, but you would never want to do so with a sword (for reasons that are outside of my knowledge base).

toapat
2019-08-01, 08:39 PM
Titanium is has a higher tensile strength than steel, but does not have the same ability to resist sheer. You would actually have to put more weight back into the blade to make it durable, reducing the weight-savings. It also has a wildly different density-per-strength profile, meaning that you would have a bit of a 'Final Fantasy' sword if you were trying to make a sword with the same strength and durability as a high-end steel sword, which sounds cool but probably makes it harder to make it actually combat effective. Mostly, it is that titanium is not naturally good at ede-holding, and can't be heat-treated as steel can be to improve this. Toapat suggests that TI-95 "is as good as Tool Steel" (not necessarily the best comparator, since we really want to compare it to sword steel). I'm certainly not an expert, but this surprises me. The old adage has been that titanium makes a great structural member in things like airplanes, since tensile strength per weight (along with not having any keystone vulnerabilities, such as being completely inflexible or the like) and lack of corrosion are primary concerns there, but modern steel is still the king of blades... and each blade is going to have their own requirements -- small pocket knives, for instance, are enhanced by some vanadium in the steel, but you would never want to do so with a sword (for reasons that are outside of my knowledge base).

1: Yes Titanium has a different strain curve then steel. It does not have a significantly different strain curve from steel in which makes it nonviable for weaponmaking

2: Again, titanium weighs 2/3rds the weight of steel for the same strength. This is true even for the weapons because you dont need to alter the dimensions for the function.

3: Titanium is straight up superior to Steel in heat treating and edge retension, i have literally no idea where you get this idea from because the problem with titanium in weaponmaking is that it will ruin its temper or overtemper itself as it is forged and ground unless carefully handled because Titanium tempers by passively cooling rather then active cooling.

4: again, theres a reason im comparing the titanium alloy against both Tool steel and springsteel at the same time, it surpasses both if you can afford to work it, which the comparison is that it is literally 1000 times harder to work then either. There is no such thing as a mass produced Sword steel, because Steel trades between strength or hardness when alloying. Titanium Alloys dont. Tool Steels are the best at sharpening, but theyre brittle. Spring steel is the highest tensile strength, but is very soft and poor at edge retention because you have to grind it once hardened, which will cause it to generate stress fractures over time.

oudeis
2019-08-01, 10:31 PM
Could you link some resources for this information? I was only able to find one reference to a Ti-95 alloy and it didn't give any specifics about the material.

Particle_Man
2019-08-02, 01:04 AM
I think there will be tales told over the generations of the fabled "light sabre", the glowing sword that could cut through *anything*. Far Future gnerations will keep looking for those wonderful, wonderful weapons. :smallsmile:

Willie the Duck
2019-08-02, 08:31 AM
Titanium is straight up superior to Steel in heat treating and edge retension, i have literally no idea where you get this idea from

I might have gotten something literally flipped. As I said, I am not an expert. I am a lot more sure on the tensile, compressive and density/strength ones, although exactly how much they contribute to material-applicability-with-regards-to-swords, I can't be sure.

Regardless, we're not going to get anywhere with dueling declaratives. Oudeis has the right of it. we need to show our work. I think those that have seen me on other subjects know I'm being consistent here in this point: since we'd all be foolish to dox ourselves and reveal our credentials, we all effectively have none, so our only expert testimony is what we can provide via externally verifiable links and documentation.

Let's be clear, I'd like you to be right. Titanium is 'cool,' in some way. Plus, it means there is some kind of alternate non-steel metal that nerds like us can pretend is mithril/mithral/adamantium/vibranium/etc. It just doesn't correspond to everything I've heard up to this point.

jjordan
2019-08-02, 10:40 AM
This is a tough subject because swords are artifacts. Which is to say that there's not a lot of demand for battlefield swords so the big brains and big money are working on other projects while a handful of enthusiasts dabble with artistic designs. If we factor in economics, and we *always* have to factor in economics, then I suspect we'd find that spring-steel swords using familiar designs are still the best solution. Remember, you have to be able to produce the weapon and maintain the weapon.

Most of the sword makers I've seen weigh in on this subject think that spring-steel (or a welded combination of spring-steel and a softer steel) is the best material for economic reasons. It's available, easy to work, there's a large body of knowledge and tools optimized for working with it, and this makes these weapons easy to maintain. They also think that sword design, for this material, has pretty much peaked. If you make the weapons sharper (without making them more brittle) then you reduce the ability to use the sword as a lever by grasping the blade with your hand. If you make the blades lighter then you're reducing the amount of force that can be brought to bear with a cut or slash.

But, bear in mind that that you're measuring swords against different scales. A simple sword manufactured using consistently high-quality alloys, with precision tools, and a work ethic that values quality would be vastly superior to anything being produced in your fallen, new bronze age. I'm not sure your smiths would be able to sharpen the blade without a lot of extra work (or at all) but your spring-steel sword (with some titanium to help keep corrosion at bay) would be far more durable than comparable bronze or iron swords. It would be lighter than bronze. It would be far more resilient than iron swords (which sometimes had to be bent back into shape during a battle).

For that matter, a titanium-aluminum alloy sword would be superior to the bronze-iron age equivalent weapons. It wouldn't corrode so that alone would be magical to most observers. It would be very light. It probably wouldn't cut as well as some well-made bronze swords, but it would do a pretty good job.

Additive manufacturing with laser sintering is allowing for some interesting metal work. I could brainstorm a spring-steel weapon with a foamed metal core that's lighter and just as strong.

toapat
2019-08-02, 11:46 AM
I might have gotten something literally flipped. As I said, I am not an expert. I am a lot more sure on the tensile, compressive and density/strength ones, although exactly how much they contribute to material-applicability-with-regards-to-swords, I can't be sure.

Regardless, we're not going to get anywhere with dueling declaratives. Oudeis has the right of it. we need to show our work. I think those that have seen me on other subjects know I'm being consistent here in this point: since we'd all be foolish to dox ourselves and reveal our credentials, we all effectively have none, so our only expert testimony is what we can provide via externally verifiable links and documentation.

Let's be clear, I'd like you to be right. Titanium is 'cool,' in some way. Plus, it means there is some kind of alternate non-steel metal that nerds like us can pretend is mithril/mithral/adamantium/vibranium/etc. It just doesn't correspond to everything I've heard up to this point.

Im going to at least trust the guys who ive seen work Titanium into weapons (https://www.youtube.com/watch?v=rtOXufkl3vw). Objectively anything that eats grinder belts is going to sharpen more effectively then Tool steels. I however previously accepted a comment on the video as correct for what material they were using, since i couldnt actually get useful documentation on materials before (google hates me arbitrarily sometimes) and assumed TI95 is the useful name of the alloy. Presumably, as the most common alloy of Titanium, theyre using Ti6Al-4V. which is still the metal they use as superstructure on combat aircraft if they can justify use of Titanium.

Now, finding strain curves on the internet is frankly infuriating. The only strain curve of Ti6Al-4V i can find is at 427C, whcih is a high enough temperature that the 275 Megapascal Yield strength the curve i can find suggesting, is completely pointless because 1095 (wikipedia says it has a yield strength of 415 MPas) would literally stretch like taffy at that temperature.

enderlord99
2019-08-02, 04:01 PM
Does sapphire fracture conchoidally, and if so, can it be (hypothetically) made as sharp as obsidian can?

Xuc Xac
2019-08-02, 04:36 PM
Does sapphire fracture conchoidally, and if so, can it be (hypothetically) made as sharp as obsidian can?

It does fracture conchoidally, but it's very hard and has a crystalline structure that breaks in three directions so it doesn't fracture smoothly like glass. It's very uneven. You could get sharp flakes, but getting even a small sapphire arrowhead would take a lot of extreme care and luck. Most likely, the big piece you're trying to shape will fracture the wrong way at least once before you finish the piece so it will be ruined.

Max_Killjoy
2019-08-02, 05:07 PM
Im going to at least trust the guys who ive seen work Titanium into weapons (https://www.youtube.com/watch?v=rtOXufkl3vw). Objectively anything that eats grinder belts is going to sharpen more effectively then Tool steels. I however previously accepted a comment on the video as correct for what material they were using, since i couldnt actually get useful documentation on materials before (google hates me arbitrarily sometimes) and assumed TI95 is the useful name of the alloy. Presumably, as the most common alloy of Titanium, theyre using Ti6Al-4V. which is still the metal they use as superstructure on combat aircraft if they can justify use of Titanium.

Now, finding strain curves on the internet is frankly infuriating. The only strain curve of Ti6Al-4V i can find is at 427C, whcih is a high enough temperature that the 275 Megapascal Yield strength the curve i can find suggesting, is completely pointless because 1095 (wikipedia says it has a yield strength of 415 MPas) would literally stretch like taffy at that temperature.

Cool video, interesting to see that at least with modern tools titanium can be made into a weapon... but not really a fair test, as the design of the claws makes for a really awkward weapon with little leverage or cutting motion, so it's hard to tell how they compare to a steel weapon. They didn't appear to do much damage really.

Xuc Xac
2019-08-02, 07:27 PM
Cool video, interesting to see that at least with modern tools titanium can be made into a weapon... but not really a fair test, as the design of the claws makes for a really awkward weapon with little leverage or cutting motion, so it's hard to tell how they compare to a steel weapon. They didn't appear to do much damage really.

That team's efforts are really more art than engineering. Very much form over function. They produce a lot of "sword-like objects". I think their main concern in tempering is to avoid dangerous or embarrassing fractures during "testing". Their testing is really ridiculous from the point of view of showing off weapon quality: "Watch our sword chop this watermelon with the same cutting power of a Macbook Air! Behold as it smashes this glass jar full of jellybeans!"

Beleriphon
2019-08-04, 10:17 AM
That team's efforts are really more art than engineering. Very much form over function. They produce a lot of "sword-like objects". I think their main concern in tempering is to avoid dangerous or embarrassing fractures during "testing". Their testing is really ridiculous from the point of view of showing off weapon quality: "Watch our sword chop this watermelon with the same cutting power of a Macbook Air! Behold as it smashes this glass jar full of jellybeans!"

Which despite some of the weird obstacles in Forged in Fire the testing really is hideously abusive and I'm impressed by how well those folks work steel.

toapat
2019-08-04, 01:10 PM
Cool video, interesting to see that at least with modern tools titanium can be made into a weapon... but not really a fair test, as the design of the claws makes for a really awkward weapon with little leverage or cutting motion, so it's hard to tell how they compare to a steel weapon. They didn't appear to do much damage really.

I wasnt really using the video as an example of a final weapon, Wolverine claws Really only become useful, in the loosest sense, If you can Somehow spin an electromagnet to Non-insignificant fractions of C to contain a Plasma Coil.

you know, the most critical limiting design factor of building a Real Lightsabre. Oh btw because of Gyroscopic stabilization good luck actually swinging something with inertia to rotation similar to that of a Planet.

What i was using it as an example of is the abrasion resistance of Titanium. If its eating steelgrinding belts, it will be sharpenable to an edge greater then any toolsteel. Its also able to take strain comparable to some springsteels, although i could not find realistic tempurature bands for it on strain curves, so i dont know how it compares when tempered, because again at 427 degrees C, both titanium and springsteels are on the edge of the Superplastic transition, at which point they will just rip apart as the energy surpasses their maximum strength.

Ya i know its an internet show where they do basically ****-all testing when they arent cutting fluid-filled plastic bottles.

King of Nowhere
2019-08-04, 01:46 PM
swords have been covered extensively; ultimately, they would work better, but not THAT MUCH better. In the end, the muscles and skill of the guy wielding the sword are always going to be the major factor.

there is another good example for artifacts, though, and it is modern body armor. there are several youtube videos showing modern motorbike helmets tested against medieval weapons (here's just one for example (https://www.youtube.com/watch?v=It5EIRZ7jOE)), and the helmet always handles it all pretty well. it is especially durable in that it does not bent out of shape after a few uses.
A modern riot armor would be superior in most regards to a medieval armor, and it probably would also be lighter and more comfortable. Most important, it is made of plastic, which means that it can conceivably last a long time (though 3000 years is actually stretching it; plastic never corrode chemically, but it become brittle and then it cracks). A riot shield would be a tower shield with very low weight and greter durability.

So you can use that for artifact.

Cikomyr
2019-08-04, 09:13 PM
swords have been covered extensively; ultimately, they would work better, but not THAT MUCH better. In the end, the muscles and skill of the guy wielding the sword are always going to be the major factor.

there is another good example for artifacts, though, and it is modern body armor. there are several youtube videos showing modern motorbike helmets tested against medieval weapons (here's just one for example (https://www.youtube.com/watch?v=It5EIRZ7jOE)), and the helmet always handles it all pretty well. it is especially durable in that it does not bent out of shape after a few uses.
A modern riot armor would be superior in most regards to a medieval armor, and it probably would also be lighter and more comfortable. Most important, it is made of plastic, which means that it can conceivably last a long time (though 3000 years is actually stretching it; plastic never corrode chemically, but it become brittle and then it cracks). A riot shield would be a tower shield with very low weight and greter durability.

So you can use that for artifact.

Am now wondering if a football or hockey armor would be better in a melee.

Pauly
2019-08-04, 10:02 PM
Im going to at least trust the guys who ive seen work Titanium into weapons (https://www.youtube.com/watch?v=rtOXufkl3vw). Objectively anything that eats grinder belts is going to sharpen more effectively then Tool steels. I however previously accepted a comment on the video as correct for what material they were using, since i couldnt actually get useful documentation on materials before (google hates me arbitrarily sometimes) and assumed TI95 is the useful name of the alloy. Presumably, as the most common alloy of Titanium, theyre using Ti6Al-4V. which is still the metal they use as superstructure on combat aircraft if they can justify use of Titanium.

Now, finding strain curves on the internet is frankly infuriating. The only strain curve of Ti6Al-4V i can find is at 427C, whcih is a high enough temperature that the 275 Megapascal Yield strength the curve i can find suggesting, is completely pointless because 1095 (wikipedia says it has a yield strength of 415 MPas) would literally stretch like taffy at that temperature.

It is a very common misconception that increased hardness = increased sharpness,

Firstly edge geometry comes into play, which has nothing to with hardness. A better designed edge will cut better.

Secondly sharpness derives from 2 factors. Up to about 4,000 grit what you are doing is making the point as pointy as it can become. After that what you are doing is making the deformations at the edge, the ‘saw teeth’ if you will finer and smaller. What drives the final level of sharpness a metal can attain is the size of the crystals. The crystals in carbon steel are finer than stainless which is why you generally can sharpen a CS knife to a finer edge than a SS knife with the same edge geometry.

What hardness counts for is edge longevity. This is not a simple case of a harder longer lasting edge is superior to a softer edge. A softer metal is much faster and easier to sharpen. I use a 1930s antique Sabatier at work and I can keep it functionally sharper than a modern J-knife with powder steel. That’s because it takes me 20 seconds with the porc fusil to get it back to screaming sharpness, but it takes 20 minutes on the stones to grind a new edge onto a powder steel blade.

toapat
2019-08-05, 02:17 AM
It is a very common misconception that increased hardness = increased sharpness,

Hardness is the material property directly responsible for the maximum possible ability to sharpen the edge geometry before we talk about molecular edges

oudeis
2019-08-05, 11:45 AM
From my days as a moderate bicycle gearhead, I know that 6-4 titanium is extremely hard and durable for a structural titanium alloy, but let's not elevate it to wonderflonium status. When titanium first became financially viable, bike builders used commercially available 3/2.5 (Al-V) aircraft hydraulic tubing from the defense industry for the frame and 6/4 AL-V stock for wheel dropouts. The 3/2.5 tubes were supposed to have almost the perfect combination of rigidity, flexibility, and resilience and 6.4 stock was extremely abrasion-resistant for a lightweight alloy and wouldn't corrode, which is very important in humid environments and areas where the roads are salted in winter. None of this makes it ZOMG the bestest stuff in teh universe for weapons. Properly formulated steel will steel have superior mechanical properties, especially for weapons.

I saw the shower of brilliant white sparks when they were grinding the blades. Very cinematic. It's worth pointing out, however, that these are coming from the metal, not the grinding medium, just as the spark from a flint firelighter comes from the steel and not the stone. As for 'eating grinding belts', that's what happens when you ablate hard metals. That's why the abrasive surface is easily replaceable. Also, and this is pure speculation on my part, but given how they were trying to hype up Awesome! factor, I have to wonder if they deliberately used less-durable media to get the vibranium-like mystique they were trying for.

Pauly
2019-08-05, 03:43 PM
Hardness is the material property directly responsible for the maximum possible ability to sharpen the edge geometry before we talk about molecular edges

You can sharpen a piece of cheese if you want to. There are plenty of you tube clips of people making sharp knives from packing tape, wood and so on. You can sharpen a toothbrush handle to a point sharp enough to kill a man.

Bronze and obsidian take sharper edges than steel, yet both are softer than steel.

Steel for armor plating is routinely hardened to 150+ Rockwell, yet even the hardest J-knives too out at about 70 Rockwell. Yet we don’t treat the steel to make knives or razors to the maximum hardness.

Hardness relates to edge durability. How long you can use the blade before needing to re-sharpen it.

A mega-titanium alloy blade might take a good edge. But every time it is used it will get less sharp. As a lost-tech artifact what that means is that when the blade gets dull, and it will get dull, it will be impossible for the finder of it to re-sharpen it.

gkathellar
2019-08-05, 04:04 PM
The premise that there's a single wonder metal that would make the perfect sword is absurd, because you don't make a high-quality sword out of a single type of metal. Different parts of a sword (core, spine, edges, tip, tang, and so on) undergo different stresses and have different needs, so the master sword-smith works together varied alloys to accomplish as many of those aims as possible. This can accomplished not only through conventional pattern-welding, but also by assembling the weapon from multiple parts, each of which can be pattern-welded individually in some cases.

Making a sword is not like making a conventional tool: the end result has to combine a variety of properties (strength, differential hardness, flexibility, a delicate balance of durability and pliability in the edge, and more) which most tools simply don't need. Complicating the matter, there's a lot about historical sword-smithing that we don't really understand (Damascus steel being the ur-question, of course), and are unlikely to understand in the near future because the effort of discovery isn't worth the research investment. High-speed steels, titanium, and more could probably be used to create superb swords, but we don't actually know how we'd do it.


What hardness counts for is edge longevity. This is not a simple case of a harder longer lasting edge is superior to a softer edge. A softer metal is much faster and easier to sharpen. I use a 1930s antique Sabatier at work and I can keep it functionally sharper than a modern J-knife with powder steel. That’s because it takes me 20 seconds with the porc fusil to get it back to screaming sharpness, but it takes 20 minutes on the stones to grind a new edge onto a powder steel blade.

And this is a big deal in general. The owner of any high-quality sword should act under the assumption that they'll be doing maintenance frequently if not constantly, and so the ability to hold an edge is only half the equation.

erikun
2019-08-05, 04:44 PM
Does it have to be a sword?

Because I'm wondering. We can manufacture diamonds. As in, real, 100% carbon diamonds. As far as I know, there isn't any real limit to how large this can be done, outside cost and practical features. It should be feasable to create one in whatever size we'd like, and either through gemcutting or through shaping it as it grows, determine some general features.

Make it an axe head. Or a pointed hammer head, if you prefer - it won't exactly be razor sharp either way. Have some sort of hexagonal- or rhombus-shaped hole running through it, to where a staff could be fashioned and fitted. The result would be something practically indestructable for any lower technology and nearly indestructable for ourselves. It would need to be a fairly large hammer head (diamond is apparently less than half the density of steel, so 2-3 times the expected size) but simply the ability to craft a weapon head out of gemstone, in such a way that it could be fitted to a haft, and for it to be nearly indestructable would be a wonder to anyone not familiar with the manufacture process. Plus, it would certainly survive 3000 years or so in the ground.

NNescio
2019-08-05, 05:19 PM
Does it have to be a sword?

Because I'm wondering. We can manufacture diamonds. As in, real, 100% carbon diamonds. As far as I know, there isn't any real limit to how large this can be done, outside cost and practical features. It should be feasable to create one in whatever size we'd like, and either through gemcutting or through shaping it as it grows, determine some general features.

Make it an axe head. Or a pointed hammer head, if you prefer - it won't exactly be razor sharp either way. Have some sort of hexagonal- or rhombus-shaped hole running through it, to where a staff could be fashioned and fitted. The result would be something practically indestructable for any lower technology and nearly indestructable for ourselves. It would need to be a fairly large hammer head (diamond is apparently less than half the density of steel, so 2-3 times the expected size) but simply the ability to craft a weapon head out of gemstone, in such a way that it could be fitted to a haft, and for it to be nearly indestructable would be a wonder to anyone not familiar with the manufacture process. Plus, it would certainly survive 3000 years or so in the ground.

Diamonds are not indestructible. They are quite fragile, actually. They cleave if you strike them the right way, and possibly even shatter. Hardness and toughness aren't the same thing. That's why you have to be careful when handling diamond tools (and rings), because they might split and shatter if you drop them. The real world is not the same as Minecraft.

Speaking of which, titanium alloys are not (usually) as hard as (hardened) steel either. Titanium is strong (especially for its weight), but strong isn't quite the same thing as hard. They are also a pain to work with (because of its thermal and chemical properties, plus its tendency to stick to surfaces, not because its "harder"!), and require specialized tools to machine or sharpen.
.
The more exotic titanium alloys like β-Ti3Au can be harder than steel, but I'm not too sure about their edge-holding properties.

King of Nowhere
2019-08-05, 06:50 PM
Complicating the matter, there's a lot about historical sword-smithing that we don't really understand (Damascus steel being the ur-question, of course), and are unlikely to understand in the near future because the effort of discovery isn't worth the research investment.

we may not know how to replicate damascus steel exactly, but we do know that it had superior properties because plant fibers used during the forgin process got reduced to carbon nanotubes, which gave superior qualities to the steel.
We are also perfectly capable of replicating that process, in fact we can do it better because we know what we're doing. modern steel outperforms damascus steel.

Vknight
2019-08-05, 07:12 PM
But carbon nano-tubes dude

Cikomyr
2019-08-05, 08:44 PM
But carbon nano-tubes dude

An accidental happy outcome, apparently.

So it's official, we can replicate Damascus Steel?

King of Nowhere
2019-08-05, 09:05 PM
An accidental happy outcome, apparently.

So it's official, we can replicate Damascus Steel?

replicate, not exactly. but we can make something that's just as good, or better.

just like we don't know the exact composition of greek fire, but we managed napalm and white phosphorous that are more effective.

Vknight
2019-08-05, 09:23 PM
An accidental happy outcome, apparently.

So it's official, we can replicate Damascus Steel?

Complicated we know the process we know the details and we have learned newer and better techniques too make steel that is better then the Damascus steel of old and how to replicate the patterns and more.

So we can make a sword that looks like it is stronger then it but is not it because we are missing the last little bit and well if we knew that it would improve t he quality of our stuff but our stuff is already better

Willie the Duck
2019-08-05, 09:40 PM
Because I'm wondering. We can manufacture diamonds. As in, real, 100% carbon diamonds. As far as I know, there isn't any real limit to how large this can be done, outside cost and practical features. It should be feasable to create one in whatever size we'd like, and either through gemcutting or through shaping it as it grows, determine some general features.

Make it an axe head. Or a pointed hammer head, if you prefer - it won't exactly be razor sharp either way. Have some sort of hexagonal- or rhombus-shaped hole running through it, to where a staff could be fashioned and fitted. The result would be something practically indestructable for any lower technology and nearly indestructable for ourselves. It would need to be a fairly large hammer head (diamond is apparently less than half the density of steel, so 2-3 times the expected size) but simply the ability to craft a weapon head out of gemstone, in such a way that it could be fitted to a haft, and for it to be nearly indestructable would be a wonder to anyone not familiar with the manufacture process. Plus, it would certainly survive 3000 years or so in the ground.

Diamonds are not indestructible. They can be shattered with rocks and burnt with significant-but-not-absurd effort.


replicate, not exactly. but we can make something that's just as good, or better.

just like we don't know the exact composition of greek fire, but we managed napalm and white phosphorous that are more effective.

Well sure, but much like the Antikythera Mechanism, it's not that we didn't have a replacement, we mostly wanted* to figure out how they did it.
*or at least I did. I guess we don't have a clear goal in mind here for this subtangent of the thread.

Pauly
2019-08-05, 09:46 PM
replicate, not exactly. but we can make something that's just as good, or better.

just like we don't know the exact composition of greek fire, but we managed napalm and white phosphorous that are more effective.

The only “lost tech” from the ancients that is being actively pursued as a modern material is Roman concrete. And I read recently that a researcher believes she has found the recipe.

A lot of the lost tech is lost not because some library got burned down, but because it got made obsolete and no one thought it was worth the time and effort to write down how to do it.

Max_Killjoy
2019-08-05, 10:08 PM
The only “lost tech” from the ancients that is being actively pursued as a modern material is Roman concrete. And I read recently that a researcher believes she has found the recipe.

A lot of the lost tech is lost not because some library got burned down, but because it got made obsolete and no one thought it was worth the time and effort to write down how to do it.


https://www.engineering.com/DesignerEdge/DesignerEdgeArticles/ArticleID/15190/The-Secret-Ingredient-in-Ancient-Roman-Concrete-is-Seawater.aspx

HighWater
2019-08-06, 04:23 AM
Maybe not a sword, but with modern material science I’m pretty sure we could make a “mithril” equivalent in terms of armor. Lightweight, but flexibile and able to take a lot of punishment.



Of course, the modern sword is actually a firearm, and so a more interesting question might be whether we could leave high-quality guns behind for future generations. Modern military grade weapons are built from durable metals and plastics and could go an awful long time without degrading. The trick is the gunpowder, which looses efficacy over time. The recovery of current-era military weaponry is a major plot point in Joel Abercrombie's Shattered Sea trilogy, but I think he just ignored the gunpowder issue.

I think these two posts are more likely to yield something that makes for a LEGENDARY relic than all this babble about a "better sword". Interesting as it may be, I think the conclusion so far is that "a sword made with all our best current techniques would surely be superior to any bronze age blade, but not LEGENDARY superior". So how about some of these artifacts that would actually be LEGENDARY to any bronze age, iron age, or even premodern culture.

A "repeating crossbow" that turns a pair of people into shield wall wrecking machines. It's called The Reaper of Armies? (chain-fed machine gun)
A "heavy crossbow" with massive range that cuts through any armor: The Thousand Step Slayer of Kings and Generals (Sniper rifle)

(We could include various missiles (GPS though?), explosives, artillery or tanks in this equation, but I do think that's beyond the spirit of the question.)

Of course, operating a machine gun or sniper rifle requires some education, but that's where the superiority of today's picture manuals comes in. It may take some pouring over to figure out the pictures without the cultural assumptions of its writers, but it's doable.

I am not 100% where plastic brittleness comes from, other than temperature issues, but if storing the items in a vacuum container doesn't fix it, it will definitely help with weapons and ammunition made solely out of metals. Make it a small, vacuum-sealed vault and its discoverers are even treated to a VERY cool sound and air effect when cracking the seal! Talk about LEGENDARY!

gkathellar
2019-08-06, 06:21 AM
we may not know how to replicate damascus steel exactly, but we do know that it had superior properties because plant fibers used during the forgin process got reduced to carbon nanotubes, which gave superior qualities to the steel.
We are also perfectly capable of replicating that process, in fact we can do it better because we know what we're doing. modern steel outperforms damascus steel.

Modern steels are remarkable and can outperform Damascus steels in a number of respect. But again, we don't know much about how to apply those modern steels to sword-making. And that's the point: we know quite a bit about making high-end steels, and somewhat less about making swords with those high-end steels (because sword-smithing is a dead field that only hobbyists care about).

I'm not arguing that the ancients did things better. They didn't. I'm arguing that we don't actually know very much about the production of high-quality swords, and that Damascus steel is a mystery of particular interest. If we knew more about sword-making we would probably be able to create exceptional swords. If we knew more about Damascus steel in particular, that knowledge would probably help with creating steels ideal for swords in particular.

Max_Killjoy
2019-08-06, 06:46 AM
There are people out there turning modern steel into swords, some of the swords are remarkable.

Willie the Duck
2019-08-06, 09:59 AM
And that's the point: we know quite a bit about making high-end steels, and somewhat less about making swords with those high-end steels (because sword-smithing is a dead field that only hobbyists care about).

I'm not arguing that the ancients did things better. They didn't. I'm arguing that we don't actually know very much about the production of high-quality swords, and that Damascus steel is a mystery of particular interest. If we knew more about sword-making we would probably be able to create exceptional swords. If we knew more about Damascus steel in particular, that knowledge would probably help with creating steels ideal for swords in particular.


There are people out there turning modern steel into swords, some of the swords are remarkable.

Both are true. Hobbyists are, fortunately, really passionate and willing to put lots of time, energy, un/under-paid labor, and oftentimes disproportionate percentages of income towards such endeavors.

Modern steel has a huge innate advantage in that, although sword-smithing is a 'dead field,' doing stuff with steel (including cutting stuff) is not, and boy howdy does having a whole industrial process where steel quality, purity, homogeneity, and ability to be heated and cooled in a controlled process is a huge benefit for the goal of making consistently good product. gkathellar is right that the specific-focus goal of making the best sword is a niche focus of that, but simply being able to say "I want X steel with Y composition and Z qualities" and being able to get specifically that is a large step in the right direction towards helping determine if that specific set of parameters is optimal towards your goals (if for no other reason than if you test said setup, and it underperforms, you know it's not because of some unknown impurity in your materials, etc.).

With regards to guns or the like, I think it depends on our goals. Are we trying to just have the future society archeologists dig it up and say, "wow they were capable of some really impressive weapons," or have the them be able to pull the weapon out of the rubble and start using it? I think the former is probably a more realistic goal because any propellants we have at our disposal that will last this unknown distance into the future will, almost by definition, be not our best propellant in broader terms.

King of Nowhere
2019-08-06, 02:00 PM
Modern steel has a huge innate advantage in that, although sword-smithing is a 'dead field,' doing stuff with steel (including cutting stuff) is not, and boy howdy does having a whole industrial process where steel quality, purity, homogeneity, and ability to be heated and cooled in a controlled process is a huge benefit for the goal of making consistently good product. gkathellar is right that the specific-focus goal of making the best sword is a niche focus of that, but simply being able to say "I want X steel with Y composition and Z qualities" and being able to get specifically that is a large step in the right direction towards helping determine if that specific set of parameters is optimal towards your goals (if for no other reason than if you test said setup, and it underperforms, you know it's not because of some unknown impurity in your materials, etc.).


yes.

most legends about "magic swords" were actually swords that by some accident of smithing and impurities got a better quality of steel. And most stories of special metals were actually caused by impurities giving better alloys. for example, iron from finland was famed for resisting corrosion; now we know it's because those iron ores have a fair amount of nickel, which would make inox steel.

nowadays, we can control precisely all that stuff, and do it reproducibly.




With regards to guns or the like, I think it depends on our goals. Are we trying to just have the future society archeologists dig it up and say, "wow they were capable of some really impressive weapons," or have the them be able to pull the weapon out of the rubble and start using it? I think the former is probably a more realistic goal because any propellants we have at our disposal that will last this unknown distance into the future will, almost by definition, be not our best propellant in broader terms.

on the other hand, maybe your heroes could find some book of instructions. gunpowder isn't hard to manifacture (at least the original version; modern high-yield powders are above the chemical prowess of ancient alchemists), and bullets compatible with a modern weapon are probably within the skill level of a master blacksmith.
so, they find a rifle and a book inside an airproof wrapping, and with that they can shoot things from afar.

Willie the Duck
2019-08-06, 02:41 PM
on the other hand, maybe your heroes could find some book of instructions. gunpowder isn't hard to manifacture (at least the original version; modern high-yield powders are above the chemical prowess of ancient alchemists), and bullets compatible with a modern weapon are probably within the skill level of a master blacksmith.
so, they find a rifle and a book inside an airproof wrapping, and with that they can shoot things from afar.

Well yes, I thought that was my point. Are our goals to give some future barbarian as the OP envisioned a really positive impression of our legendary weaponry skills, or to give them something they themselves can use in their conquests. :smalltongue:

jjordan
2019-08-06, 08:19 PM
If the sword is going to be a firearm then how about an upscale version of the Girandoni air-rifle? Pump it up and it fires a large caliber bullet. Using carbon-fiber, ceramics, and designing for the lowest common denominator user you could have something quite useful. With a pump or lever action you could even fire multiple shots before having to recharge the weapon.

Excession
2019-08-06, 11:38 PM
on the other hand, maybe your heroes could find some book of instructions. gunpowder isn't hard to manifacture (at least the original version; modern high-yield powders are above the chemical prowess of ancient alchemists), and bullets compatible with a modern weapon are probably within the skill level of a master blacksmith.
so, they find a rifle and a book inside an airproof wrapping, and with that they can shoot things from afar.

Gunpowder isn't so bad, but the primer would be harder to make. Fulminate of mercury percussion caps are early 1800's tech though, so it might be possible to get that process worked out while only losing a few fingers. A flint-lock musket is a pretty simple device though, you just need good enough steel that it doesn't blow up when you fire it.

I think the important thing for modern industry isn't just that we could make a really good sword. It's that we could make a factory to make millions of consistently really good swords, if we needed to. You don't find a single magic sword, you find a shipping container full of them.

Psyren
2019-08-07, 09:03 AM
Carbon Fiber maybe? Strong, light, heat resistant etc.

I think armor might be the bigger draw than weapons personally. I could see a kevlar vest being a marvel in a future pseudo-medieval era. I mean, if it can stop bullets then it's got to be good against arrows, right?

*I'm assuming in both cases these materials have been stored in a long-term way, I have no idea how feasible that is.

Max_Killjoy
2019-08-07, 09:08 AM
Gunpowder isn't so bad, but the primer would be harder to make. Fulminate of mercury percussion caps are early 1800's tech though, so it might be possible to get that process worked out while only losing a few fingers. A flint-lock musket is a pretty simple device though, you just need good enough steel that it doesn't blow up when you fire it.

I think the important thing for modern industry isn't just that we could make a really good sword. It's that we could make a factory to make millions of consistently really good swords, if we needed to. You don't find a single magic sword, you find a shipping container full of them.

Good point -- if we really needed to make combat-worthy swords, we'd industrialize the process, with tolerances that would be far better than most of the wall-hanger junk made today, but not as good as the best masterworks.

Willie the Duck
2019-08-07, 09:20 AM
I think armor might be the bigger draw than weapons personally. I could see a kevlar vest being a marvel in a future pseudo-medieval era. I mean, if it can stop bullets then it's got to be good against arrows, right?

Well, quite literally no. Something can be good against a bullet and bad against an arrow. Certainly something can be good against a bullet and just plain awful against knives (which are different from arrows, I recognize).

Psyren
2019-08-07, 09:30 AM
Well, quite literally no. Something can be good against a bullet and bad against an arrow. Certainly something can be good against a bullet and just plain awful against knives (which are different from arrows, I recognize).

Would that be true regardless of what the arrows are made from? we could even be going back to stone-tipped here.

toapat
2019-08-07, 10:37 AM
https://www.engineering.com/DesignerEdge/DesignerEdgeArticles/ArticleID/15190/The-Secret-Ingredient-in-Ancient-Roman-Concrete-is-Seawater.aspx

Basically use poor quality concrete because it has "sediment traps" that change how it reacts to erosion forces


Well, quite literally no. Something can be good against a bullet and bad against an arrow. Certainly something can be good against a bullet and just plain awful against knives (which are different from arrows, I recognize).

Arrows will not penetrate Kevlar, they carry significantly lower kinetic momentum and outside bodkin points will not be as condusive to penetration.

A knife can penetrate Kevlar because it is not a single burst of energy that has to be dissipated quickly, its a continuous application of force. Like a stab from a regular person ive heard delivers 40 times as much energy as a 5.56 Nato Round on the thrust.

Like, IRL the reason we dont care for melee weapons in armed forces as more then a survival tool and weapon of last resort is our ranged weapons have really surpassed our practical armor technology. WH40k is actually kinda right in that if we can outfit our basic infantry in armor that can straight up take hits from anything man portable currently in existence, while nothing man portable becomes more practical, the Mace will at least become a practical weapon again (Arguably the Powersword, Power Axe, Chainsword and Chain axe would not make a return because they try to sunder the armor rather then transfer energy through it.)

King of Nowhere
2019-08-07, 12:00 PM
on the other hand, a flak vest is very light and flexible and would protect the joints - which are the weaker parts of an armor handsomely.

So, wearing a flak jaket under a full plate and with a motorcycle helmet on your head would make you almost invulnerable to middle age weaponry.

Anyway, I specified riot armor instead of bulletproof vest because they are very different in design and what they can do. sure, the plate of a bulletproof vest would take several hits of anything medieval before shattering. but it's only a plate. it's designed because it's impossible with current material technology to have an armor that can protect all the body and move in it, so you only cover the vital areas and you trust in statistics. A sword can still hit everywhere else, so a bulletproof vest is no better than a breastplate against a sword.

there's also an underlying philosophy and economy of human life. in modern society when a child is born the society spends money in hospital chiildbirth, public healtcare, publich schooling. We make few children and we invest heavily on them. We also have good medical technology, so a bullet on the leg is not fatal and the wounded person can generally go back to fighting after a while. So we give armor to soldiers because soldiers are expensive and we can recover a wounded soldier.
In medieval society there were always more children than society needed. there was no public healtcare to speak of, no public school to speak of, nothing really. recruiting a youth from the fields was practically free, and if he died, you could always recruit another. If you didn't send them to die in war, they'd grow until they surpassed the carrying capacity of agriculture, and then they'd die of famine instead. At the same time medicine was bad, so a soldier with a leg wound had a good chance to die from infection or to stay a cripple even if he survived. definitely cheaper to let the guy die and recruit someone elsse.

toapat
2019-08-07, 07:09 PM
So, wearing a flak jaket under a full plate and with a motorcycle helmet on your head would make you almost invulnerable to middle age weaponry.

As far as combat stresses are concerned, a motorcycle helmet would be destroyed without offering meangingful protection. They are designed to work once really well, and then be thrown out.

Max_Killjoy
2019-08-07, 07:33 PM
As far as combat stresses are concerned, a motorcycle helmet would be destroyed without offering meangingful protection. They are designed to work once really well, and then be thrown out.

More broadly, a lot of modern safety gear is designed so that it's destroyed, instead of your body part or whole body. See, the crumple zones in cars, even.

King of Nowhere
2019-08-07, 08:10 PM
As far as combat stresses are concerned, a motorcycle helmet would be destroyed without offering meangingful protection. They are designed to work once really well, and then be thrown out.

there are plenty of videos of people trying medieval weapons on helmets, and helmets always prove very resilieent to multiple blows. I linked some in one of my previous posts, when i suggested the idea the first time.

the part about "you have to throw it away after one blow because it's not as safe anymore" is half exaggeration and half protection from lawsuits. sure, the helmet actualy weakens a bit, but taking another hit that's just strong enough to destroy the weakened helmet but weak enough that the new helmet would have survived would be an extreme coincidence.

anyway, all armor takes damage.

Excession
2019-08-07, 09:31 PM
Good point -- if we really needed to make combat-worthy swords, we'd industrialize the process, with tolerances that would be far better than most of the wall-hanger junk made today, but not as good as the best masterworks.

Even at that top end, do any master smiths test and x-ray their blades to find flaws? That's pretty typical for high end steel products like jet engine turbine blades, or even buildings.

toapat
2019-08-08, 08:52 PM
there are plenty of videos of people trying medieval weapons on helmets, and helmets always prove very resilieent to multiple blows. I linked some in one of my previous posts, when i suggested the idea the first time.

the part about "you have to throw it away after one blow because it's not as safe anymore" is half exaggeration and half protection from lawsuits. sure, the helmet actualy weakens a bit, but taking another hit that's just strong enough to destroy the weakened helmet but weak enough that the new helmet would have survived would be an extreme coincidence.

anyway, all armor takes damage.

Combat Helmets which are designed to distribute and resist impact are extremely different from motorcycle helmets which are designed to crumple and absorb impact. If they werent able to basically destroy the target, they were not using either combat techniques which will definitely sunder the helmet, or weapons so blunt they couldnt cut paper.

And a motorcycle helmet can "look" fine, because it has large quantities of rigid foam to absorb impact with. like a fortification it can be cosmetically fine, but the protection expended in a single strike means that theres nothing keeping you safe, and thats with a fresh helmet. Motor Cycle Helmets dryrot, so unless you keep it underwater in a sealed vessel under argon, its not going to be good 2 years from now.

Any of the evolutionary line of the Buckethelm would be superior to a Motorcycle helm in combat.

jjordan
2019-08-08, 10:04 PM
Most armor is ablative in nature. Medieval inventories showing pieces of armor and partial suits seem to make it clear that armor was regularly too-damaged to be used. And modern armor is the same way. Kevlar is discarded after it takes damage, and that includes helmets. An acquaintance of mine was shot in the head by a sniper in Iraq. He still has the helmet. Most fantasy games fall down in tracking how much work has to go into keeping armor functional.