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Post by dwwolf on May 2, 2017 10:52:54 GMT
Graphene is supposed to be graphene sheets bonded together. 3d graphene is supposed to be an Areo foam based on graphene. Both IIRC.
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Post by Enderminion on May 2, 2017 11:32:15 GMT
I quite like the jet black of diamond, but 1/2mm of anything, spaced a few cm is not THAT massive
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Post by dwwolf on May 2, 2017 12:00:28 GMT
You could change limits.txt if it has a minimum armor layer thickness. 20ųm gold or silver look purty.
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Post by Enderminion on May 2, 2017 12:26:00 GMT
You could change limits.txt if it has a minimum armor layer thickness. 20ųm gold or silver look purty. or gold and silver
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Post by dwwolf on May 2, 2017 12:34:37 GMT
Which is what I said. 20 micrometers of Gold or Silver.
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Post by gedzilla on May 2, 2017 12:46:16 GMT
Honestly, I just kinda want a good armor composition that's light, and well, don't end up in black. My armor composition with diamond, amorphous carbon, graphite gel and boron is super good, but it's kinda dull when everything is black... u could always add the thinnest layer possible of that green colored armor...
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Post by demetrious on May 2, 2017 19:22:16 GMT
Yes they do interact between layers. I coat my armor with 500micron aluminum coat, the same material used in 77nm laser mirrors. It works really well against those extreme UV lasers. Now, aluminum is a good mirror, but it cannot withstand that much heat. Aluminum alone would melt instantly under such laser. (As proven by stock designs) Graphene and 3d-graphene filler under that aluminum on the other hand have really high spec-heat and thermal conductivity. They absorb the heat from the aluminum layer and spread them all over the hall, making the aluminum last much longer. Thank god, you've ended my paranoid delusions. So many screenshots of a railgun-riddled test target on my hard drive, as I pour over them, muttering what does it meaaan!? It can be hard to analyze cause and effect sometimes because you've only the visual cues to work with, and those are limited for various practical reasons. The Mysterious Vanishing Crew Module is my biggest challenge, because visual evidence of spalling damage can be quite hard to spot sometimes. Then there's also shock and possible nuclear effects, which is also complicated by detonators being a little finicky - I've had shells from the stock nuclear cannon fail to detonate entirely. The shells hit the well-armored test target and the heavy, dense uranium core just punches right through for a kinetic kill. From after-affects damage - with a single hole in the outer whipple shield, but glowing, heated armor only on the interior - it can be hard to tell if the missile physically penetrated the whipple shield before detonating and causing the backstop layer to spall and penetrate subsequent layers, or if the whole thing was an accidental nuclear EFP affect from the nose-cone armor (on my missile designs.) Also, that heat-sink inner layer/aluminium outer layer design for anti-laser defense is brilliant. I've been looking for a way to exploit the reflectiveness of aluminum for laser defense for a while now but couldn't find a good application. I'll be stealing that. Mass also plays an important role. Its illustrated pretty decently by my graphene armor scheme ( probably broken to begin with ). Top to bottom. 2cm Si-gel. 1mm graphene 1m void 4mm graphene 5cm Al-foam. 2mm graphene. Is generally quite sturdy. However changing the 4mm graphene layer by a 4mm maraging steel layer led to less leakers. The physical stats of maraging steel are worse ( very respectable overall ofcourse ) but I think the ~35x sectional density offered by the maraging steel does more to slow down projectiles in combination with the Al-foam and graphene backstop. Mass does indeed matter. Consider the kinetic energy equation: K = 1/2 mv2 (m = mass, v = velocity.) It's easy to see why railgun designs favor tiny masses at high velocities; the velocity has a much larger say in the eventual kinetic energy delivered. It's also much easier to accelerate lower-mass projectiles, because of inertia, the measure of a body's resistance to changes in velocity (a body at rest tends to stay at rest, etc.) The equation for inertia is simply p = mv. In short, mass is a lot more significant in inertia than it is in total kinetic energy. Thus your marang steel layer, with its 35x superior sectional density, has a lot more effective inertia, and thus negates more of the incoming projectile's inertia. Very dense materiel is valued as armor for planetary applications because mass is usually less of a concern than volume, but in space the opposite holds true, which is why bulkier, lighter armor tends to be favored. I learned that the hard way when I realized my complex composite armor designs, using thin layers of high-grade materiel, were being outperformed by the simple stock ship armor designs, with a simple whipple shield and a thick layer of carbon or ceramic beneath it. When you take into account how that inertial relationship between railgun rounds and armor encourage them to deflect very easily, however, dense armors become more attractive; since a round that skips off imparts a lot less kinetic energy (and thus does a lot less damage) to the armor, allowing it to outlast a mass-equivalent layer of amorphous carbon. You just need to angle your ship right, of course. Apropos of nothing, but how do you tell when a crew module's been destroyed by radiation effects from nukes? Does the crew module actually vanish, as if it'd been hit with weapons fire normally?
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Post by alias72 on May 2, 2017 21:08:27 GMT
So. Is it feasible to armour a ship against hyper-velocity projectiles without using sacrificial armour (Whipple shield) or composites over 3 layers (surface interior and spall liner). Is their a metric for armour effectiveness. If not may one be created. what is the minimum reasonable angle at which a hardened monolithic plate can be expected to force a ricochet from a selection of stock/near stock weapons.
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blkcandy
Junior Member
Burn complete. Crawling back to bed.
Posts: 78
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Post by blkcandy on May 2, 2017 22:52:50 GMT
My main kinetic battle drone sloped armor is 62m long and has a diameter of 26. Its whipple shield is made of 500micron aluminum and 500micron graphene backed by 3d-graphene filler underneat.
It deflect pretty much all stock weapon with only aluminum surface peeled off. Even the whipple shield itself last a few seconds under full gunship fire before it finally start doing its duty as a whipple shield layer.
Deflecting stock weapon shouldn't be that hard.
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Post by demetrious on May 4, 2017 19:30:25 GMT
So. Is it feasible to armour a ship against hyper-velocity projectiles without using sacrificial armour (Whipple shield) or composites over 3 layers (surface interior and spall liner). Actually, it might be - and without steep angling. Now the nature of hyper-velocity projectiles is such that in a straight-on, 90 degree angle impact, the energies are so high that both armor and projectile behave like fluids rather than solids. They mutually annihilate each other. Hence the whipple shield concept. The problem with whipple shields is the spacing required; the 100cm minimum you see used on most stock ships is a good rule of thumb. You can build multiple-barrier shields, where the second and subsequent barriers serve both as the backstop to the first shield, but are light enough to function as a good Whipple shield for barriers behind them... but the spacing required to make it effective greatly increases the amount of effective volume you have to armor, and starts costing you in mass. From what I've seen the best compromise is, again, what you see used by stock ships in-game - the whipple shield outer layer, backed by a rather thick layer of light, strong, and bulky ceramics. The hypervelocity k-slugs are going to put a good crater in whatever they hit, no matter what, so you want your armor's thickness to exceed the depth of that crater. Railgun slugs will just blast clean through a thin layer of VC steel with a good right-angle impact, and the dense VC steel just adds to the dangerous shrapnel and superheated plasma spraying your delicate crew modules. But equivalent mass in bulky and light amorphous carbon needs to be chewed through with multiple impacts. tl;dr against hypervelocity impacts, all armor is effectively ablative, with even enclosed vacuum working for you, and the challenge lies in balancing armored volume with mass.
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Post by tukuro on May 5, 2017 0:19:33 GMT
So. Is it feasible to armour a ship against hyper-velocity projectiles without using sacrificial armour (Whipple shield) or composites over 3 layers (surface interior and spall liner). Is their a metric for armour effectiveness. If not may one be created. what is the minimum reasonable angle at which a hardened monolithic plate can be expected to force a ricochet from a selection of stock/near stock weapons. Yes. Hyper-velocity projectiles tend to be low-calibre (in the gram range), which break up or plasmify upon impact with high density materials. Creating effective kinetic armour hinges on this principle. You do this by defeating it in several stages. First you break it up. Then you absorb the energy of the secondary debris, slowing it down. And finally you absorb whatever energy remains. Now, I see a lot of people here with either massive monolithic armour or soft outer layers, and from my experience that just isn't efficient. I try to keep the armour as percentage of total mass and cost in the single digits. Preferably adding negligible mass and making sure the cost stays at around 5% max of the total. Adequate kinetic armour consists of the following parts: Outer Bumper: This breaks up the projectile.
Desired Properties: - Dense. So that it can absorb the kinetic energy of the initial impact. I forgot the name of the principle behind this, so if anyone could help me out and name it, that be great.
- Cheap. So as to keep the cost of your armour to a minimum. As the outer layer it tends to have the highest surface area.
- Melt Easily. With a low melting temperature and heat capacity. This might seem contradictory, but you want the outer bumper to melt or plasmify upon contact, Expanding plasma is a lot less dangerous than solid ejecta consisting of high density flakes traveling at hyper-velocities. This means you have one less thing to worry about.
Options: Tin, Cadmium or Lead. All these materials share the above properties. Why not use osmium/platinum/diamond/boron/a-carbon/fibre?: Yield strength is less important here. The alternatives are either too expensive, have low density or tend to produce high-velocity ejecta that can damage ship internals. Stuffing: This helps absorb and spread out the impact energy. Desired Properties: - High Heat Capacity: Specific heat and melting temperature. So as to absorb the plasma.
- High Yield Strength: So as to absorb the kinetic energy of secondary debris.
- Low Density: So as to give the plasma enough time to expand, and the debris to spread out.
- Cheap: From my experience stuffing is the most expensive part of the armour.
Options: Graphite Aerogel or Silica Aerogel. Assuming the thermal conductivity has been fixed, the graphite aerogel can double as laser armor, but it isn't as effective as Silica Aerogel. Silica gel is more expensive but it can double as a potent thermal armour layer. Why not use rubber/fibre?: Too expensive. Stuffing the shield with aramid, UHMDPE or nitrile rubber (which can double as laser shielding) will balloon the cost and mass of the ship.
Bumpers: This is mostly to catch solid debris. You can build a shield using only one outer bumper, stuffing and a spall liner. But using multiple bumpers tends to substantially increase the survivability of a ship. Desired Properties: - High Yield Strength: To absorb the kinetic energy.
- Low Moduli: So that it remains flexible, and doesn't spall and produce more secondary debris upon impact.
Options: Spider Silk. I've found this to be a very cost effective solution assuming your stuffing is wide enough to absorb, or let expand any plasma. Why not use steels/metals/alloys/high-moduli fibres?: These either are a lot more expensive, or they tend to spall due their high moduli and/or low speed of sound. In contrast spider silk tends to disintegrate or tear, rather than shatter. Spall Liner: This catches any remaining debris and protects the internals. Desired Properties:- High Moduli: Making sure it doesn't tear.
Options: Boron or Amorphous Carbon. It's a cheaper light weight alternative to ceramics and steel. Why not use steel/ceramic/fibre?: Too expensive, and adds unnecessary mass. Either Boron or A-Carbon are sufficient. Example Armour:
- Outer Bumper: 500 μm of either Tin or Cadmium. (Mostly cadmium. I like to integrate the outer layer directly into the paint job, Cadmium makes for a glossy black.)
- Stuffing: 20 cm of Graphite Aerogel.
- Bumper: 1 mm of Spider Silk.
- Stuffing: 20 cm of Graphite Aerogel.
- Spall Liner: 500 μm of Boron.
When angled (or at lower volumes) this makes those gram-sized hyper-velocity (15-50 km/s) pellets bounce right off.I also recommend reading this paper ston.jsc.nasa.gov/collections/TRS/_techrep/TP-2003-210788.pdf, it covers the basics of whipple shield design and explains the principles behind it.
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Post by Owlfeathers on May 5, 2017 1:31:41 GMT
Honestly, I just kinda want a good armor composition that's light, and well, don't end up in black. My armor composition with diamond, amorphous carbon, graphite gel and boron is super good, but it's kinda dull when everything is black... u could always add the thinnest layer possible of that green colored armor... Neptunium? It costs an absolutely ludicrous amount to even have a 500 micron thick layer composing a narrow band which takes up 1% of your ship's length. ... And now I'm just imagining some naval engineer burning a few gigacredits of the navy's budget "armouring" a ship in Neptunium because he really wanted a green spaceship and high command refused to give him a paint budget. That'll teach them.
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Post by gedzilla on May 5, 2017 7:31:38 GMT
Well, there is always gold I guess. ..
Try 500microns if that
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Post by gedzilla on May 5, 2017 7:44:47 GMT
So. Is it feasible to armour a ship against hyper-velocity projectiles without using sacrificial armour (Whipple shield) or composites over 3 layers (surface interior and spall liner). Is their a metric for armour effectiveness. If not may one be created. what is the minimum reasonable angle at which a hardened monolithic plate can be expected to force a ricochet from a selection of stock/near stock weapons. Yes. Hyper-velocity projectiles tend to be low-calibre (in the gram range), which break up or plasmify upon impact with high density materials. Creating effective kinetic armour hinges on this principle. You do this by defeating it in several stages. First you break it up. Then you absorb the energy of the secondary debris, slowing it down. And finally you absorb whatever energy remains. Now, I see a lot of people here with either massive monolithic armour or soft outer layers, and from my experience that just isn't efficient. I try to keep the armour as percentage of total mass and cost in the single digits. Preferably adding negligible mass and making sure the cost stays at around 5% max of the total. Adequate kinetic armour consists of the following parts: Outer Bumper: This break up the projectile.
Desired Properties: - Dense. So that it can absorb the kinetic energy of the initial impact. I forgot the name of the principle behind this, so if anyone could help me out and name it, that be great.
- Cheap. So as to keep the cost of your armour to a minimum. As the outer layer it tends to have the highest surface area.
- Melt Easily. With a low melting temperature and heat capacity. This might seem contradictory, but you want the outer bumper to melt or plasmify upon contact, Expanding plasma is a lot less dangerous than solid ejecta consisting of high density flakes traveling at hyper-velocities. This means you have one less thing to worry about.
Options: Tin, Cadmium or Lead. All these materials share the above properties. Why not use osmium/platinum/diamond/boron/a-carbon/fibre?: Yield strength is less important here. The alternatives are either too expensive, have low density or tend to produce high-velocity ejecta that can damage ship internals. Stuffing: This helps absorb and spread out the impact energy. Desired Properties: - High Heat Capacity: Specific heat and melting temperate. So as to absorb the plasma.
- High Yield Strength: So as to absorb the kinetic energy of secondary debris.
- Low Density: So as to give the plasma enough time to expand, and the debris to spread out.
- Cheap: From my experience stuffing is the most expensive part of the armour.
Options: Graphite Aerogel or Silica Aerogel. Assuming the thermal conductivity has been fixed, the graphite aerogel can double as laser armor, but it isn't as effective as Silica Aerogel. Silica gel is more expensive but it can double as a potent thermal armour layer. Why not use rubber/fibre?: Too expensive. Stuffing the shield with aramid, UHMDPE or nitrile rubber (which can double as laser shielding) will balloon the cost and mass of the ship.
Bumpers: This is mostly to catch solid debris. You can build a shield using only one outer bumper, stuffing and a spall liner. But using multiple bumpers tends to substantially increase the survivability of a ship. Desired Properties: - High Yield Strength: To absorb the kinetic energy.
- Low Moduli: So that it remains flexible, and doesn't spall and produce more secondary debris upon impact.
Options: Spider Silk. I've found this to be a very cost effective solution assuming your stuffing is wide enough to absorb, or let expand any plasma. Why not use steels/metals/alloys/high-moduli fibres?: These either are a lot more expensive, or they tend to spall due their high moduli and/or low speed of sound. In contrast spider silk tends to disintegrate or tear, rather than shatter. Spall Liner: This catches any remaining debris and protects the internals. Desired Properties:- High Moduli: Making sure it doesn't tear.
Options: Boron or Amorphous Carbon. It's a cheaper light weight alternative to ceramics and steel. Why not use steel/ceramic/fibre?: Too expensive, and adds unnecessary mass. Either Boron or A-Carbon are sufficient. Example Armour:
- Outer Bumper: 500 μm of either Tin or Cadmium. (Mostly cadmium. I like to integrate the outer layer directly into the paint job, Cadmium makes for a glossy black.)
- Stuffing: 20 cm of Graphite Aerogel.
- Bumper: 1 mm of Spider Silk.
- Stuffing: 20 cm of Graphite Aerogel.
- Spall Liner: 500 μm of Boron.
When angled (or at lower volumes) this makes those gram-sized hyper-velocity (15-50 km/s) pellets bounce right off.I also recommend reading this paper ston.jsc.nasa.gov/collections/TRS/_techrep/TP-2003-210788.pdf, it covers the basics of whipple shield design and explains the principles behind it. I tend to take a vastly different approach; I have wipple shields that are stiff (Boron/amorphous carbon) stuffing, silica aerogel, and then a very thick plate of something very strong (boron) with a spall liner behind that (arimid fiber). This armor is designed to reflect, not obsorb. Imho u are right about needing less dense armors if they are to be chewed thru. But if they are designed to reflect, imo its more important for the armor to be dense and very strong. This (deflection approach to armor) requires very heavy angling, but my ships always resemble needles anyway. And it is a very massy and costly approach -if you put it over the whole length of the ship. I dont of course, its usually only on the top 20%, which is all the enemy ever sees anyway (with nose foward)
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Post by dwwolf on May 5, 2017 8:27:19 GMT
Yes they do interact between layers. I coat my armor with 500micron aluminum coat, the same material used in 77nm laser mirrors. It works really well against those extreme UV lasers. Now, aluminum is a good mirror, but it cannot withstand that much heat. Aluminum alone would melt instantly under such laser. (As proven by stock designs) Graphene and 3d-graphene filler under that aluminum on the other hand have really high spec-heat and thermal conductivity. They absorb the heat from the aluminum layer and spread them all over the hall, making the aluminum last much longer. Thank god, you've ended my paranoid delusions. So many screenshots of a railgun-riddled test target on my hard drive, as I pour over them, muttering what does it meaaan!? It can be hard to analyze cause and effect sometimes because you've only the visual cues to work with, and those are limited for various practical reasons. The Mysterious Vanishing Crew Module is my biggest challenge, because visual evidence of spalling damage can be quite hard to spot sometimes. Then there's also shock and possible nuclear effects, which is also complicated by detonators being a little finicky - I've had shells from the stock nuclear cannon fail to detonate entirely. The shells hit the well-armored test target and the heavy, dense uranium core just punches right through for a kinetic kill. From after-affects damage - with a single hole in the outer whipple shield, but glowing, heated armor only on the interior - it can be hard to tell if the missile physically penetrated the whipple shield before detonating and causing the backstop layer to spall and penetrate subsequent layers, or if the whole thing was an accidental nuclear EFP affect from the nose-cone armor (on my missile designs.) Also, that heat-sink inner layer/aluminium outer layer design for anti-laser defense is brilliant. I've been looking for a way to exploit the reflectiveness of aluminum for laser defense for a while now but couldn't find a good application. I'll be stealing that. Mass also plays an important role. Its illustrated pretty decently by my graphene armor scheme ( probably broken to begin with ). Top to bottom. 2cm Si-gel. 1mm graphene 1m void 4mm graphene 5cm Al-foam. 2mm graphene. Is generally quite sturdy. However changing the 4mm graphene layer by a 4mm maraging steel layer led to less leakers. The physical stats of maraging steel are worse ( very respectable overall ofcourse ) but I think the ~35x sectional density offered by the maraging steel does more to slow down projectiles in combination with the Al-foam and graphene backstop. Mass does indeed matter. Consider the kinetic energy equation: K = 1/2 mv2 (m = mass, v = velocity.) It's easy to see why railgun designs favor tiny masses at high velocities; the velocity has a much larger say in the eventual kinetic energy delivered. It's also much easier to accelerate lower-mass projectiles, because of inertia, the measure of a body's resistance to changes in velocity (a body at rest tends to stay at rest, etc.) The equation for inertia is simply p = mv. In short, mass is a lot more significant in inertia than it is in total kinetic energy. Thus your marang steel layer, with its 35x superior sectional density, has a lot more effective inertia, and thus negates more of the incoming projectile's inertia. Very dense materiel is valued as armor for planetary applications because mass is usually less of a concern than volume, but in space the opposite holds true, which is why bulkier, lighter armor tends to be favored. I learned that the hard way when I realized my complex composite armor designs, using thin layers of high-grade materiel, were being outperformed by the simple stock ship armor designs, with a simple whipple shield and a thick layer of carbon or ceramic beneath it. When you take into account how that inertial relationship between railgun rounds and armor encourage them to deflect very easily, however, dense armors become more attractive; since a round that skips off imparts a lot less kinetic energy (and thus does a lot less damage) to the armor, allowing it to outlast a mass-equivalent layer of amorphous carbon. You just need to angle your ship right, of course. Apropos of nothing, but how do you tell when a crew module's been destroyed by radiation effects from nukes? Does the crew module actually vanish, as if it'd been hit with weapons fire normally? I dont think CoaDE models crew radiation damage. ( Other than thermal radiation/temperature ). Otherwise megaton nukes going off < 1km would instantly incapacitate crew without very bulky shielding. In atmosphere the shielding provided by air makes radiation effects mostly superfluous since you would be flash charred or reduced to pulp by air pressure anyway at the ranges where it would be a concern. In space however blast is pretty much irrelevant and thermal and other radiation dominate the weapon effects.
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