Unrealistic SCI-FI metals

aerius · Post by **aerius** » 2002-12-27 08:27pm

Wicked Pilot wrote:TAKE THIS ENGINEERS!

http://edj.net/Plates/SouthCentral/MSY_ir10%233.GIF

Oh cool, a landing chart for an airport with the approach angles and stuff. Now I just gotta figure out what all the numbers mean. I will soon return to my materials rant.

Post by **Colonel Olrik** » 2002-12-27 08:39pm

Wicked Pilot wrote:TAKE THIS ENGINEERS!

Oh, I can feel the jealousy

Your puny landing scheme is no match for the power of a fully grown engineer!

http://personal.smartt.com/~sansell/images/ckt_chrg.jpg

Wicked Pilot · Post by **Wicked Pilot** » 2002-12-27 08:45pm

Colonel Olrik wrote:Your puny landing scheme is no match for the power of a fully grown engineer!

If you thought that approach plate was complicated, just wait until I start pulling out some aircraft performance charts. Muwhahahahahah...

Einhander Sn0m4n · Post by **Einhander Sn0m4n** » 2002-12-27 08:47pm

Wicked Pilot wrote:TAKE THIS ENGINEERS!

http://edj.net/Plates/SouthCentral/MSY_ir10%233.GIF

Any idea why you picked my city's airport chart over any other? LOL

beyond hope · Post by **beyond hope** » 2002-12-27 08:47pm

I'm curious as well: if rarity or difficulty in working a given metal or alloy wasn't a factor, would something else be preferrable to steel? I was wondering in particular about depleted uranium as starship armor. Also, I've seen zero-G forging mentioned in some novels and was wondering about it's actual usefulness. Lastly, would a (obviously theoretical) material combining the characteristics of metal and plastic be useful for anything or not?

Wicked Pilot · Post by **Wicked Pilot** » 2002-12-27 08:53pm

Einhander Sn0m4n wrote:Any idea why you picked my city's airport chart over any other? LOL

I thought about doing one from Chicago O'Hare, but I've never actually flown into there. I have however done a few touch'n go's over at Mosiant while getting my multi rating over at Lakefront.

Warspite · Post by **Warspite** » 2002-12-27 08:59pm

Ah, Ah! YES, found something to add to the pics, behold, the hydraulic main power system for an US sub (WWII vintage, granted).

http://www.maritime.org/fleetsub/hydr/img/fig7-02.jpg

And it's still very simplified!

NOW I'M BEING BAD!

aerius · Post by **aerius** » 2002-12-27 09:35pm

beyond hope wrote:I'm curious as well: if rarity or difficulty in working a given metal or alloy wasn't a factor, would something else be preferrable to steel? I was wondering in particular about depleted uranium as starship armor. Also, I've seen zero-G forging mentioned in some novels and was wondering about it's actual usefulness. Lastly, would a (obviously theoretical) material combining the characteristics of metal and plastic be useful for anything or not?

I don't know enough about depleted uranium to comment on it. Other materials, titanium is being considered as a replacement for steel in some applications mainly for weight saving purposes. They're also using metal & ceramic composite plates in some bullet proof vests, though I'm not sure why. My guess is that sweat will cause rust in steel plates but who knows? These plates are roughly 0.5-1" thick and are in conjunction with the kevlar vests they can stop anything up to a 7.62mm NATO rifle round. The bullets will damage the plates though, and they're good for less than 10 hits at most. A good armour steel plate half that thickness will bounce the same bullets off it all day with minimal damage.

As for zero-g forging that stuff's a myth as far as I know. While it's true that they can grow better crystals in zero-g, gravity doesn't do anything bad to steel. What messes up steel is air and unwanted impurities, which is why high grade steels are processed in a vacuum. The really good stuff is double vacuum melted to get rid of all the impurities, and the ingots get rolled in several directions to get a better grain size and structure.

For high-alloy tool steels they may also pour the molten steel into a gas jet that "aerosols" the molten steel. Instead of having it cool into an ingot and grow big grains, it gets blown into tiny steel balls which have really small grains due to the fast cooling rate. They then heat the balls and squeeze them into an ingot with a big hydraulic press, then it gets rolled out into bars. The resulting steel has a really fine grain structure and distribution, which makes it tougher and more resistant to fractures. They can also make alloys this way that they can't make with normal methods because of carbide segregation, grain growth, and other such stuff.

Post by **Beowulf** » 2002-12-27 09:36pm

Colonel Olrik wrote:
Wicked Pilot wrote:TAKE THIS ENGINEERS!
Oh, I can feel the jealousy

Your puny landing scheme is no match for the power of a fully grown engineer!

http://personal.smartt.com/~sansell/images/ckt_chrg.jpg

A battery charger. Wow...

/me wishes he knew where to find a fuel line diagram for the SR-71...

Wicked Pilot · Post by **Wicked Pilot** » 2002-12-27 09:59pm

The Duchess of Zeon · Post by **The Duchess of Zeon** » 2002-12-27 10:25pm

beyond hope wrote:I'm curious as well: if rarity or difficulty in working a given metal or alloy wasn't a factor, would something else be preferrable to steel? I was wondering in particular about depleted uranium as starship armor. Also, I've seen zero-G forging mentioned in some novels and was wondering about it's actual usefulness. Lastly, would a (obviously theoretical) material combining the characteristics of metal and plastic be useful for anything or not?

I don't know about Zero-G forging, but there are some things you can do to steel to improve its quality as armour. If you make steel more than about three and a half inches thick, in fact, failure to do these things will generally cause it to shatter when it is hit by rounds with a certain striking velocity.

Anyway, the process by which you improve steel as an armour is called face-hardening, and the various versions of that include Krupp Cemented and Harveyized Nickel Steel. (There was also an earlier simple Nickel Steel.) Krupp Cemented Armour got to 35% of the armour thickness. With other versions (Harveyized Nickel Steel) you could super-harden the first inch or so and do the same treatment to a noticably lesser degree on the rest. Remember that this was the 1890s and the process has improved since then.

Basically, you're going to have to find a way to face harden the steel in a space combat vessel really good against kinetic energy attacks. I'd actually consider putting in a decapping layer to any armour scheme if railgun use is prevalent; they didn't work very well in wet-navy battleships but the alternatives tried there aren't available in deep space, and combined with hull curve it might work.

SWPIGWANG · Post by **SWPIGWANG** » 2002-12-27 10:37pm

So back to materials.

So are we doomed and no Deathstar is ever possible without unobtainium??????

Since steel's strengh lies in its structure, can we make uber (better) materials if we could to the same to other materials???? (damn I'm asking for a imperial smackdown...nooooooooooo

)

Buah ah ah! You wish you knew the difference between martensitic, ferritic and austenitic steel

LETS GO GOOGLEGUNIN

From my lame text into level text book.

Austenite is a solution of iron carbide in iron....
Martensite is a varient of iron-carbon crystal which is extreamly hard...
Ferrite is pure iron....

http://www.avestapolarit.com/template/Page____2470.asp

between granular and grey molten iron, Why is dura-aluminium the way to go and what the fuck is a CK45 quality tempered carbon steel?

Damn you....

As for dura-aluminium.....hmmmm all the goodness of aluminium without the corrision?

It's not that bad yet, we have yet to discuss stress/strain curves, elongation,

When young's modulus isn't enough....

retained austenite in steels, fatigue & corrosion micro-fracture propagation, secondary hardening tool steels and all that other fun stuff.

fatigue = bend that wire 10 times and it breaks

and damn you too.... how fracture propagation itself works is annoying enough.... (stored strain energy something)

Your puny landing scheme is no match for the power of a fully grown engineer!

Just a circuit with a microchip, a few resisters, power supplies and transisters thrown in.

kojikun · Post by **kojikun** » 2002-12-28 01:43am

--Your puny landing scheme is no match for the power of a fully grown engineer!--

Oh please.

http://www.solorb.com/elect/fmst/SillScem.gif

kojikun · Post by **kojikun** » 2002-12-28 02:00am

erk..

Post by **Darth Wong** » 2002-12-28 02:01am

I can't be bothered to read this page of replies because the giant picture makes it really wide and it's a pain in the ass to read.

SyntaxVorlon · Post by **SyntaxVorlon** » 2002-12-28 02:08am

I was not saying that WTC towers would have kept standing had the girders been ceramic I am simply using that as an example of why in a battle where energy weapons were being used steel would lose it's toughness.
I was also not saying that the space craft in question should be a terracotta vase with chickenwire inside, I was saying that a thick protective layer of durable ceramic armor with an sub hull of steel for support, the steel would be protected by the ceramic armor because it does not transfer heat, the reason that ceramics are useful in this situation exactly, the steel supports the armor and absorbs the physical impact of the plasma volley and keeps the ceramics from shattering. Which they would be less likely to do then you think, ceramics can be very durable, especially in the case of plasma, or hot fast moving projectile gases, but their heat resistance is what makes them useful in this situation. Lasers would be infact less damaging because they would also not break through the ceramic hull and would have less physical impact.

Post by **Darth Wong** » 2002-12-28 02:12am

Nope, ceramic tiles are good for re-entry protection because they ablate and conduct heat poorly. This does NOT mean they're necessarily good protection against lasers; they are not reflective and their low thermal conductivity means zero heat spreading, so the concentrated energy will blast away a ceramic very efficiently. You should not equate apples and oranges.

kojikun · Post by **kojikun** » 2002-12-28 02:25am

::chortle:: theres nothing worth reading, my lord

kojikun · Post by **kojikun** » 2002-12-28 02:27am

hows this for a hull: near perfect reflector made of a superconducting matrial.

Shinova · Post by **Shinova** » 2002-12-28 02:30am

kojikun wrote:hows this for a hull: near perfect reflector made of a superconducting matrial.

I'm sure an explosive weapon would take care of that, or a physically piercing weapon.

Or are you referring to a material that reflects ALL energy?

SWPIGWANG · Post by **SWPIGWANG** » 2002-12-28 02:38am

Anyway, the process by which you improve steel as an armour is called face-hardening, and the various versions of that include Krupp Cemented and Harveyized Nickel Steel. (There was also an earlier simple Nickel Steel.) Krupp Cemented Armour got to 35% of the armour thickness. With other versions (Harveyized Nickel Steel) you could super-harden the first inch or so and do the same treatment to a noticably lesser degree on the rest. Remember that this was the 1890s and the process has improved since then.

A soft metal cap on the shell can nullfy the projectile shattering effects of face hardened armor, making it useless.....

And if it is hypervelocity, the shell would melt itself and then the armor and I don't think hardening helps.

There is a reason face hardened armor is phased out mid WWII....

Post by **Darth Wong** » 2002-12-28 02:44am

Actually, the bulk characteristics of armour are already very good in terms of simultaneously balancing toughness, hardness, and tensile strength. Case-hardening doesn't hurt, but it really doesn't contribute that much to stopping crack growth, unless the impactor is so soft that it doesn't penetrate the case-hardened layer (not the case with specialized anti-armour weapons).

If you could stack hard and soft layers that would be very handy, but that seems rather impractical for such large amounts of metal.

The Duchess of Zeon · Post by **The Duchess of Zeon** » 2002-12-28 03:47am

Darth Wong wrote:Actually, the bulk characteristics of armour are already very good in terms of simultaneously balancing toughness, hardness, and tensile strength. Case-hardening doesn't hurt, but it really doesn't contribute that much to stopping crack growth, unless the impactor is so soft that it doesn't penetrate the case-hardened layer (not the case with specialized anti-armour weapons).

Hrmm. I understood that one of the main problems can actually be that the impactor may dislodge a "plug" of armour from the impact point; usually in pieces but sometimes as a single piece, which can travel into the hull to cause damage.

http://www.warships1.com/W-Nathan/index.htm

- That's where I've gotten most of my information.

If you could stack hard and soft layers that would be very handy, but that seems rather impractical for such large amounts of metal.

Well, on very early battleships they used a layering of Steel/Iron/Wood - "Compound Armour" - as the armour scheme. 3in of steel, usually, and you could get up to a foot and a half of iron - that sounds pretty impressive, but the belt was quite narrow - And it could easily be backed by a foot or more of wood to cushion it all.

I'd been wondering if a sandwiching of Steel/Ceramics/DU in series might be effective on spaceships, not necessarily in that order and probably with multiple layers of each.

Also:

http://www.warships1.com/W-Tech/tech-085.htm

- Do you think that railgun shells would be built with an AP cap, and thus that efforts towards decapping would be worthwhile? I've always conceived of them (railguns), as being simply a space-usage gun; at least until you can get enough of a fraction of c behind them so that the KE can do the job on its own.

The Duchess of Zeon · Post by **The Duchess of Zeon** » 2002-12-28 03:53am

SWPIGWANG wrote: A soft metal cap on the shell can nullfy the projectile shattering effects of face hardened armor, making it useless.....

And if it is hypervelocity, the shell would melt itself and then the armor and I don't think hardening helps.

There is a reason face hardened armor is phased out mid WWII....

EDIT: Apology there; I just checked in Friedman and you're right; they used STS which was homogenous by that time, along with a decapping plate.

Hypervelocity assumes a sufficient fraction of c as to go far behind the technology we can feasably see, I think; and armour is melted today, without rendering such considerations in armour design less relevant. It's about more than material and thickness...

A soft cap, btw, will deform on impact with any iron or steel plate. Sufficient for me.

Enlightenment · Post by **Enlightenment** » 2002-12-28 03:56am

kojikun wrote:hows this for a hull: near perfect reflector made of a superconducting matrial.

Near perfect mirrors are near impossible to maintain in real-world conditions outside of clean rooms. They also won't do much good if the enemy is unsporting enough to shoot at you with lasers (e.g. deep UV) that aren't reflected by mirror coatings.